FormZ 7 - Animation Manual

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2001 Riverside Drive Product Information & Support TEL: (614) 488-8838Columbus, Ohio 43221 (614) 488-9777 FAX:(614) 488-0848

Animation ManualEIGHTEENTH EDITION

JULY 2012

COPYRIGHT: © AutoDesSys, Inc., 2012. All rights reserved.

No part of this publication may be reproduced, stored in a retrieval system, transcribed, transmitted, or translated into any language in any form by any means without the written permission of AutoDesSys.

This document was created electronically using Adobe InDesign® on an Apple Macintosh® computer.

TRADEMARKS: form•Z®, RenderZone®, and bonzai3d are trademarks of AutoDesSys, Inc.

Apple, Macintosh, and OS X logos are registered trademarks or trademarks of Apple Computer, Inc. Microsoft, all variations of Windows, and the Windows logo are registered trademarks or trademarks of

Microsoft Corporation.All other products mentioned in this document are registered trademarks or trademarks of

their respective owners.

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Contents

The Animation tools 44 Keyframe tool 45 Animate along Path tool 49 The Animate Entities tool 55 The Animate Object Options dialog 55 Animation Group Tool 59 Creating and querying animation groups 61 Animation deformations 63 Animated Deform Tools 65

Extract Animation 71 Reverse Animation 72 Replace Animation 74

Using common modeling tools on animated entities 78 Operating on an animated entity 78 Operating on keyframes 79 The range of the Transform tool 80

Animating color 81 Animating materials 82 Animating material colors 83 Animating the frame time parameter of map based shaders 84 Animating numeric shader parameters 85 Preview icons of animated materials 86 Animated color options 87 Animated color example 88

Generating and saving animations 89 Generating animations 89 Exporting animations 95

Tutorials 97

Swinging door tutorial 98 Animation Editor palette 100 Adding Keyframes 102 A door swinging in the breeze 104

Bouncing Ball Tutorial 106 Advanced motion: squash and stretch 111

Animating Materials 114 Animating the color of the ball 115 Animating the color of the floor 116

Introduction 1 The Animation Process 3 Using the Keyframe tool 3 Using the Animate Along Path tool

6 Using the Animate Entities tool 7 Animating through the Animation Editor palette 8 Animating parameters 8 Numeric control of animated information 9 Fine tuning, rendering, viewing, and exporting animations 10 Rendering an animation 10 Viewing an animation 10 Exporting an animation 10 The animation preferences 11 Animation Options 12 Timing Tab 12 Preview Tab 13 Settings Tab 15

Animation Time Line Palette 17 The Animation Editor Palette 21 The Animation Score section: context menu 23 The Add Tracks dialog 23 Graph 25 Editing control points and curves 26 Cutting, copying, and pasting control points 28 Zooming, fitting, and panning the graph 30 Aligning control points 31 Setting the current time 31 The Key section 31 Track Options... 33 The Graph Options... Button 36

Animation controller functions 39 Stacking controllers 39 The Bezier controller 39 The Sine controller 40 The Noise controller 42 Controllers may also have tracks 43

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Contents

Rendering the animation 117 Animating lights and cameras 119 Animating the camera 120 Animating the cone light 121

Animating parts of objects 124 Keyframing Points 124 Animating point along a path 126

Animating deformations or dancing board 127

A movie within a movie 132

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Animation Introduction

Animation is a sequence of images displayed one after another fast enough to give the impression of motion. form•Z can animate objects and lights in addition to views (cameras). In this write-up, we shall be using the term entity to represent all the items that can be animated in form•Z, namely objects, lights, and cameras, whenever a text applies to all of them.

Motion is created by animating the position and orientation (rotation) of the entities. In addition, most parameters of an entity can be animated to change the appearance of the entity over time. Each parameter or piece of information about an entity that can be animated is called a track. Typi-cally, an animated entity has a number of tracks. The change in value of a track during the animation is determined by one or more animation controllers associated with the track. The controllers determine how the track’s value changes over time. The controllers define the key values for a track at specific points in time and define the method for interpolating the time between the key values. The relationship between the animated enti-ty, its tracks, and the tracks’ control-lers are represented in form•Z in a hierarchical fashion. This hierarchy can be inspected in the Animation Editor palette.

As shown in the Example, an ani-mated scene may consist of any number of entities, which appear as folders with the usual right point-ing triangle in front of them. Click-ing on this triangle opens the folder and exposes the tracks of the entity. The tracks are also folders that can be opened to show the controllers they contain.

There are nine standard tracks that are used for most entities. These control the position (in X, Y and Z), rotation (in X, Y and Z), and scale (in X, Y and Z) of the entity. Addi-tional tracks are available depend-ing on the type of entity. For ex-ample, height may be a track of an animated object. Most parameters of objects, lights, and views that are user controllable can be animated.

The Animation Editor palette with its folders (a) closed and (b) open.

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A corresponding track is available for each parameter that can be ani-mated. For example, in an object of revolution, the revolution angle can be animated using the revolution track. The number of tracks available is dependant on the characteristics of the entity. Only parameters that can be animated have corresponding tracks (i.e. an object’s name is not ani-matable).

The default controller is the Bezier controller. All tracks are initially created with this controller. The Bezier controller uses a Bezier curve to determine the change in a track’s value between key values. This controller can be complemented or replaced with additional controllers such as the noise or sine controller.

A frame of the animation that contains at least one track and one control-ler with a key value is called a keyframe or simply key. The program in-terpolates between the keyframes to derive in-between frames. All the frames together, when played at a proper speed, produce an animation or a movie.

Setting up and editing animations in form•Z is supported by a number of tools, dialogs, and palettes. There three items in the Palettes menu that open the Animation Time Line, Animation Options and Animation Edi-tor palettes.

The first step in building an animated scene is to create the entities to be animated (often in their expected starting position). The object axis is the base that is used for controlling the position, rotation, and scale of an animated object. That is, when the object is animated, the transformations applied to the object to create motion are applied relative to the object's axes. The axis can be edited graphically using the Edit Axis tool ( ) and numerically by picking the object and clicking the Info tab in the Tool Options palette. For views, the animation is based on the eye point and/or the center of interest. For lights, the animation is based on the origin of the light. Direct, cone, and projector lights also can be controlled by their center of interest.

The next step is to tell form•Z that you want the entity to be animated (all entities are static until animated). The third step is to define the key values for the entity. The remainder of the process is to refine the key values and controller parameters until the entity is animated as desired. Note that it is possible to work on multiple entities simultaneously and the process often involves tuning the animation parameters for all entities as the scene evolves. The Animation Time Line palette can be used to preview the animation in either wireframe or interactive rendering modes during the construction process.

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The animation process

There are four ways to convert a static entity into an animated entity. An animated entity is an entity that can change its position or shape over time. Once an entity is animated, it is listed in the Animation Editor palette that lists all of the animated entities in the project.

Using the Keyframe tool ( )

The Keyframe tool is discussed in more detail in the Animation Tools section. When the tool is used on a static entity, it makes the entity ani-mated and creates default tracks and default keys for the current state of the entity at the current time. A Bezier controller is created for each track with a single key representing the current state. At this point, as there is only a single keyframe, the entity will not actually change when the current time is changed in the Animation Time Line palette. The next step is

Auto key framing: (a) A cube is animated using the Keyframe

tool (current time = 0). (b) Current time is set to 5 and the cube is moved to the desired location.

(c) Current time is set to 2.5 and the cube is again moved with the Move tool. (d) The cube is moved to a new location for time of 2.5

seconds.

to add additional keyframes to define the state of the entity at additional key points in time. Additional key frames can be added using auto keyframing or manual keyframing methods.

With auto keyframing, form•Z au-tomatically adds and updates keys when required as an entity is edited. That is, as changes are made us-ing form•Z tools and dialogs, these changes are automatically reflected in the animation of the entity. Automatic key framing is controlled by the Auto Keyframe icon ( ) in the Animation Time Line palette. Auto keyframing is on by default.

To add a key with the auto method, first set the current time to the desired time for the new key using the Anima-tion Time Line palette. Next make the desired changes to the entity. As the changes are made, the necessary keys are added to the controllers to keep the animation on track with the changes. The process is repeated as many times as needed to produce the desired results.

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When auto keyframing is disabled, manual keyframing can be used to add keys. To add a key with this method, first set the current time to the desired time for the key using the Animation Time Line palette. Next, perform the necessary operations to the entities or edit their parameters to establish the desired state of the entity for the time. At this point the entity is said to be off track. That is, it is not in a state that is represented by the animation tracks. Once the desired state is achieved, click on the object using the Keyframe tool. This establishes a new keyframe at the desired time. If a keyframe already exists at the current time, its values are changed to the new values. The entity is no longer off track. The process is repeated as many times as needed to produce the desired results.

Manual key framing: (a) A cube is animated with the Keyframe tool (current time = 0).

(b) Current time is set to 5 and the cube is moved to the desired location. (c) The cube is clicked with the Keyframe tool to add a new key frame.

(d) Current time is set to 2.5 and the cube is moved again. (e) The cube is clicked with the Keyframe tool to add a key frame.

(f) Cube is moved to a new location. (g) The cube is clicked with the Keyframe tool to update the key frame.

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Entity Off Track alert dialog.

If an animated entity is off track and the current time is changed using the Animation Time Line palette, the Entity Off Track warning is issued as shown below. This offers the opportunity to retain the state of the off track entities.

Keep Entities Off Track: Clicking on this button keeps the off track enti-ties in their off track position and parameters. This allows for the current time to be changed without losing the changes to the entities. The entities can then be keyframed at the new time with the Keyframe tool.

Keyframe Changed Entities: Clicking on this button keyframes all of the off track entities at the current time. This is equivalent to selecting all of the off track objects with the Keyframe tool.

Cancel: If you click on this button leaves the current time unchanged.

Do Not Keep Changes: If you click on this button the changes made to the off track entities are discarded and the entity goes back to its position for the new time.

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Using The Animate along Path tool ( )

The second method is to use the Animate along Path tool, which is dis-cussed in more detail in the Animation Tools section. This tool makes an object animated such that its position and rotation are controlled by a path defined by a form.Z object. The tool creates default path tracks and default keyframes. A Bezier controller is created for each track with a keyframe at the start and a keyframe at the end of the path. The entity is animated from the start to the end of the path. The path object is not changed by the op-eration, hence if the path is edited, the animated entity follows the updated path.

Animate along Path tool: (a) The original cube and spline path.

(b) The cube is made animated by activating the Animate along Path tool and clicking on the cube and the spline path.

(c) The current time is changed to 5 seconds. (d) The spline path is edited by using on screen controls.

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Using the Animate Entities tool ( )

The third method is to use the Animate Entities tool, which uses a set of existing entities to create a single animated entity. To do this, prepick the objects you wish to animate, using the Pick tool, and then, with the Animate Entities tool active, click anywhere in the project window. Note that it only makes sense to pick objects that are copies of the same object. When dissimilar objects are picked, the first one will be the entity that will be animated. The others will only be used for their location and orienta-tion.

Each of the selected entities represents a keyframe of the animation se-quence. This tool provides similar functionality to the Animation From Keyframes menu command found in previous versions of form•Z.

Using the Animate Entities tool: (a) The original cube.(b) The cube copied and positioned at desired locations.

(c) With the Pick tool, the cubes are preselected in the desired order and then, with the Animate Entities tool active, we click anywhere in the project

window.

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Animating parameters

In addition to animating an object's position, rotation, and scale, most entities’ parameters can be animat-ed as well. A corresponding track is available for each parameter that can be animated. By default, when an entity is made animated, tracks are created for the primary parameters of entities. These are the parameters that are commonly animated and are found in nature. There are a variety of ways to con-trol which parameter tracks are created, as discussed in later sec-tions.

Parameter tracks are also added by default when a keyframe is added (using auto keyframing or with the Keyframe tool) and a parameter is changed. That is, if a parameter has a different value at the time the key is inserted than the adjacent keys, the parameter track is added and the necessary keys are created. If an object is already animated, pa-rameter tracks can also be added manually by right clicking the name of the object in the Animation Editor palette and selecting Add Tracks... from the context menu.

Animating the height of a cube with auto keyframing: (a) The cube is

made animated by using the Key-frame tool with current time = 0.

(b) Time is set to 5, cube is moved to a new location, and its height is

changed using on screen controls(c) Current time is set to 4 seconds. (d) The height is changed using using on screen controls (e) Current time

is set to 2.5 seconds.

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Animating through the Animation Editor palette

The final method is to drag the name of an object, light, or view from the Objects, Lights, Views, or Materials palette into the Animation Editor pal-ette. This is done by placing the mouse on the name in the desired palette, clicking on the name and holding the mouse button down to drag it to the desired position in the Animation Editor palette. As with the first method, default tracks and controllers are created with single key values for the current state.

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Numeric control of animated information

Some dialogs contain parameters that are animatable, indicated by a small bullet to their right. This bullet is also a menu that pops up when pressing the mouse cursor on it. The bullet graphic representation changes to reflect the status of the parameter, as follows:

[ ] The parameter is animatable, but is currently not animated. If there is no graphic present, then the parameter is not animatable.

[ ] The parameter is animated and its current value represents a key value at the current time.

[ ] The parameter is animated and the current value does not represent a key value.

[ ] The parameter is animated, but the track is currently locked so the pa-rameter cannot be changed.

The bullet menu contains four items used to control the animation state of the parameter as follows:

Add Track: The track for this parameter is added and a key is added for the current value at the current time. This is only available if the parameter is not animated (the track does not exist).

Add Key: A key is added for the current value at the current time. This is only available if the parameter is animated and there is not already a key at the current time.

Remove Key: The current key associated with the value is deleted. This is only available if the parameter has a key at the current time.

Delete Track: The track corresponding to the parameter is removed and the parameter is no longer animated. This is only available if the parameter is animated and is not locked.

The Add Track popup menu from the Material Parameters palette.

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Fine tuning, rendering, viewing, and exporting animations

The creation of a successful animation usually requires refinement of the animation parameters to achieve the desired results. Using the keyframing techniques described earlier allows for control of the critical values in the ani-mation, however, it does not offer control over the transition between the key frames. This can be controlled using the Animation Editor palette. This palette offers complete control over the details of the track and controller pa-rameters.

Rendering an animation

An animation is rendered by selecting Generate Animation... from the Display menu. Selecting this item invokes the Animation Generation dialog, where generation parameters can be set, including the type of ren-dering and the name of the file into which the animation will be stored. Clicking Generate Animation... starts the rendering process during which a progress bar dialog continuously displays the frame number that is cur-rently rendered, the rendered image is displayed in the screen background and the rendered frames are entered in the Animation Time Line palette. After the process is completed the animation is saved in a file carrying the name entered in the Animation Generation dialog and the suffix “.fan”, which stands for “form•Z animation.” Note that this is a form•Z internal for-mat that cannot be read by another application. To open the animation in another program it will need to be exported to another format.

Viewing an animation

An animation can be played by selecting the Play Animation... item in the Display menu, which first invokes the Animation Playback dialog for setting the playing parameters. When clicking on OK, the animation is run. The screen is cleared and only the animation window appears. If Loop was selected in the Animation Playback dialog, the animation plays con-tinuously by looping back to its beginning, until it is interrupted by pressing esc or command+period (Macintosh) or ctrl+period (Windows).

An animation can also be viewed using the View File menu command. When the Open File dialog is invoked you can select the “.fan” file you wish to view.

Exporting an animation

To be able to take the animation to another application, it needs to be saved accordingly. From the File menu you select Export Animation.... This invokes an Open File dialog where the form•Z animation file to be exported is selected. A File Save dialog is then invoked for selection of

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the format and name of the file to be exported. Animations can be ex-ported to formats including QuickTime or AVI (Windows) or as a set of independent image files (such as TIFF or Targa).

After a QuickTime (.mov) or AVI (.avi) file has been exported, it can also be played from within form•Z. This is done by selecting View File... from the File menu. When the Open File dialog is invoked you can select the animation file you wish to view.

The animation preferences

The animation features of form•Z can be turned on or off through an option in the Animation tab of the Preferences dialog, invoked by clicking on the Preferences... item in the Edit menu.

Enable Animation: When this option is on, the animation features in form•Z are active and usable. They are disabled otherwise.

The Animation tab of the Preferences dialog.

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Animation options

General options that apply to all animation data for a project are found in the Animation Options palette. This dialog can be opened from the Palettes Menu and is divided into three tabs, Timing, Preview, and Set-tings.

The Timing Tab

Temporal Settings: This section controls the time and frame rate informa-tion for the animation.

Start Time: This parameter indicates the animation’s starting time. The default is zero.

End Time: This parameter indicates the animation’s end time. The default is 10 seconds.

Duration: This parameter indicates the animation’s duration, from start to end.

Frames: This field represents the total number of frames in the ani-mation. This number equals Duration in seconds multiplied by Frames Per Second.

Frames Per Second: This is a combined numeric field and pop up menu. Certain preset values can be selected from the pop up menu, or any value can be typed in the field. This value is the rate at which the frames are played when viewing an animation. The higher the frame rate, the smoother the animation appears when replayed. The default frame rate is 30, which is sufficient for the human eye to experience flicker free motion.

The above parameters are interrelated. That is, when one is changed, the others are also adjusted so that they all display the correct values.

• When Start Time or End Time are changed, Durations and Frames are adjusted. • When Duration or Frames Per Second are changed, End Time and Frames are adjusted. • When Frames is changed, Duration and End Time are adjusted.

The Animation Options: Timing tab.

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It is important to note that, when animated entities exist in the project, changing the start time, end time or duration could leave these entities out of the time range of the animation. For example, an object that is ani-mated starting at one second and ending at four seconds would be out of the animation range if the start time was changed to 5 seconds. When the Animation Options dialog is closed, and the start time, end time, or duration have been changed, a warning dialog is presented which offers the option for the existing animated entities to be adjusted to the new parameters so they are proportional to the previous settings. If the start and end times are changed but the duration remains the same, the time values for the animated entities are shifted. If the duration is changed, then the time values are scaled into the new duration.

Time Display Format: This pop up menu controls how time fields are displayed throughout the animation interfaces.

Seconds: Time fields are displayed as seconds. This is the de-fault option.

HH:MM:SS: Time fields are displayed with 3 numbers separated by colons for hours, minutes, and seconds.

HH:MM:SS:Frames: S.M.P.T.E standard time code format of hours: minutes: seconds: frames (within last second). Frames: Time fields are displayed as frames.

Loop: The animation plays continually. When it reaches the end time, it continues on from the start time. This is the default option.

Palindrome: This choice also continually plays the animation, but upon reaching the end time, playback is reversed until the start time is reached again, at which point playback is reversed again and this cycle repeats.

The Preview Tab

Preview Playback: This sec-tion controls how the animation playback occurs.

Loop Control: This menu contains three looping options which control what happens when the end time is reached while playing an animation. This option can also be controlled using the corresponding options in the Animation Time Line palette. The Animation Options: Preview tab.

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No Loop: The animation is played to the end time and stops

Enable Frame Skipping: When this option is on, the playback will stay “on time” independent of the underlying graphics hardware. If for whatever reason during playback the hardware takes too long to display a frame, this playback option will cause the playback to skip frames that technically should have already passed in time. Turning this option off makes sure that each frame is displayed and is useful for verifying the state of all frames of the animation. This option is on by default.

Range: These fields affect the range of the playback time. These op-tions can also be controlled using the corresponding graphic controls in the Animation Time Line palette.

Start Time: Time at which playback starts.

End Time: Time at which playback ends.

Entity Preview: These options determine how an animated entity (throughout its animated life span) is displayed in the modeling window. These options are useful for motion analysis in being able to visualize all at once the places the entity will be. Note that these options are check boxes and more than one can be on at the same time. With all of these options off, only the entity is drawn at its location for the current time.

Show Keyframes: When selected, the state of the entity at each of its keyframes is shown. This is on by default.

Show At Interval n: When selected, the state of the entity at each interval of n seconds is shown.

Show n Frames Before Current At Interval m: When selected, the state of the entity is shown n times at a specified time interval (m), before the current frame.

Show n Frames After Current At Interval m: When selected, the state of the entity is shown n times at a specified time interval (m), after the current frame.

Show Trail: When selected, the trail of the entity through time is shown. This is the path that the centroid of the entity follows during the course of the animation.

Use Controller Cache: With this option enabled, each value of each controller is computed once for each frame and stored in memory for fast playback. However, as the number of controllers grows, responsiveness in general may become slower due to high memory consumption on com-puters with limited availability of RAM. If this option is off, less memory is used by the animation system, since only the current frame is stored in memory. However, the controller values must be generated on the fly for

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each frame change, which increases the burden on the CPU.

Use Object Cache: With this option enabled, each object that is animated is computed and stored in memory for each frame of the animation. As the number of animated objects grows, the same memory performance issues described for the controller cache apply.

The Settings Tab When An Entity Changes Its Parent, Keep Current Location: Since each parent has its own coordinate system, moving a child from one parent to another could affect the child's own coordinates. This setting affects animated entities' current position and orientation when an entity moves from one parent to another parent. If checked, the animated

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Previewing an animated entity using: (a) Show Keyframes, (b) Show At In-terval n, (c) Show n Frames Before Current At Interval m, (d) Show n Frames

After Current At Interval m, and (e) Show Trail .

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entity's apparent location stays the same, even though it moves to a new coordinate system, meaning that its coordinates are changed to match the same location. If this option is not checked, the animated en-tity's coordinates do not change, and therefore the entity tends to visibly shift as it moves to its new parent's coordinate system. However, its same coordinates are now just being interpreted relative to its new parent.

When Adding An Entity To Animation Score: These op-tions affect entities that become animated as you move them into the Animation Score palette from another palette, or click in the Animation Score palette (when cre-ating a new group).

Create Initial Tracks: If checked, then tracks are initially created for the newly animated entity.

Default Tracks: This adds only those tracks marked with a default status.

Transformation Tracks: This adds only the standard transformation tracks.

User Selected Tracks: This allows the user to select which tracks are added via a dialog.

Default Group Name: This string is used to create default names for animation groups. By default this string is “Animation Group.”

The Animation Options: Settings tab

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The Animation Time Line palette and its functions, for keyframe based time control.

The parts of the Animation Time Line palette are noted as follows:

The time line is a ruler (horizontal line with measurements) across the middle of the palette. It represents time, the positions of the keyframes in time, and the current time. By default the time line shows the entire length of the animation. The left edge is the start or zero time position. The right edge is the end of the animation and the length of the time line represents its duration. The ruler markers and labels on the top portion of the time line indicate the frame numbers. The lower marks and labels indicate time. The size of the marks and intervals depend on the duration of the animation and the size of the Animation Time Line palette, which can be resized.

: This symbol, located on the slider bar above the timeline is the cur-rent time marquee. This indicates where along the time line the pres-ent time is positioned. The position of the current time can be changed by clicking anywhere along the time line, which causes the current time marquee to move to the new location. The time marquee can also be dynamically changed by clicking and dragging it along the time line. When the current time is changed, the image in the active modeling window is refreshed to show the new view. Pressing the shift key when moving the current time will delay the redraw of the view, until the key is released. This is useful when complex scenes are animated. When the time line is zoomed (see below) and the complete time line does not fit and is not displayed in the palette, it will autoscroll when moving the current time marquee beyond its left or right edge.

The Animation Time Line palette

The primary function of the Animation Time Line palette is to control the current animation time and to preview the animation sequence. The current animation time is the point in time that is reflected in the modeling window and is used in animation operations.

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A blue line is used to represent the keyframes and their position on the time line. Keyframes are editable from the Animation Editor palette and cannot be directly edited from the Animation Time Line Palette.

: These represent the start and end time for playing an animation on the time line. When the Play ( ) or Play Reverse ( ) buttons are selected, the animation is played between the start and end symbols. The start or end can be changed by clicking on the respective symbol and dragging it along the time line. Double clicking the start time slider sets the playback start time to the animation start time. Double clicking the end time slider sets the playback end time to the animation end time. • Pressing command (Macintosh) or ctrl (Windows) while double clicking on the start time slider, sets the playback start time to the first keyframe. • Pressing command (Macintosh) or ctrl (Windows) while double clicking on the end time slider, sets the playback end time to the last keyframe.

The eight icons in the lower left of the palette control the playback op-erations of the animation in the active window. They are similar to the controls found on a VCR or DVD player.

Start: When this item is selected, the current time is moved to the start time.

Previous Keyframe: When clicking on this button, the current time is moved back to the previous keyframe. If the current keyframe is the first frame, the current time jumps to the last keyframe of the anima-tion.

Previous Frame: When clicking on this button, the current time is moved back one frame. If the current frame is 0, the current frame jumps to the last frame of the animation. Holding the mouse button down keeps advancing frames.

Play Reverse: When this item is selected, the animation is played in the active modeling window moving backward through time.

Stop: When this button is pressed, the playback is stopped.

Play: Same as Play Reverse except that the animation is played forward. Next Frame: Same as Previous Frame except that the anima-tion is advanced to the next frame.

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Next Keyframe: Same as Previous Keyframe except that the animation is advanced to the next keyframe. End: When this item is selected, the current time is moved to the end time.

Loop Control: This button toggles through the three available looping options used when playing an animation. Each click toggles to the next option and the icon changes to reflect the active option as fol-lows: Loop: The animation continually plays. When it reaches the end time, it continues on from the start time. This is the default option.

Palindrome: This choice also continually plays the anima-tion, but upon reaching the end time, playback is reversed until the start time is reached again, at which point playback is reversed again and this cycle repeats.

No Loop: The animation is played to the end time and then stops

Auto Keyframe. This button turns on/off auto keyframing. If auto keyframing is on, then when an animated entity is edited, keyframes are automatically created for the tracks currently present on the entity. If off, the Keyframe tool or the Animation Editor palette can be used to add keyframes. Pressing option (Macintosh) or ctrl (Windows) while clicking on this button opens the Auto Keyframe Options dialog, whose options are the same with those found in the Keyframe Options dialog, invoked from the Keyframe tool.

The box labeled Time, located next to the playback buttons, displays the current time numerically. The format is determined by the Time Display Format option set in the Animation Options dialog. The current time can be changed by entering the desired time in the text field.

The box labeled Frame displays the current frame based on the cur-rent time. As the current time moves, this number is updated to the frame number the current time marquee is on. The current frame can be changed by entering the desired time in the text field.

The four icons at the lower right portion of the Animation Time Line palette are buttons for zooming and panning the time line.

Zoom in: Clicking on this icon zooms in the resolution of the

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time line by 50%. This enlarges the graphic detail of the time line ruler. The zoom is performed relative to the current time and the time marquee remains visible.

Zoom out: Clicking on this icon zooms out by 200%, up to the limits of the duration of the animation. This has the reverse effect of the Zoom in operation.The scroll wheel of a mouse can also be used to zoom the time line in and out.

Fit: Clicking on this icon fits the entire time line in the palette. Pressing control (Macintosh) or ctrl + alt (Windows) while clicking on this icon, will fit the time line to the playback range of the animation.

Pan: Clicking on this icon makes the pan tool active. When active, clicking and dragging in the time line scrolls the time line with the movement of the mouse. It can also be scrolled without selecting the icon by pressing control (Macintosh) or ctrl + alt (Windows) while click-ing and dragging the time line. This functionality is only available when the time line has been zoomed in. The middle mouse button can also be used to pan.

The Animation Time Line palette has the usual window controls:

• It can be closed by clicking on the close button at its upper left cor-ner. When closed it can be invoked and opened by selecting the Anima-tion Time Line item in the Palettes menu. • It can be hidden by clicking on the hide button, which is the triangle in its upper right corner. • It can be resized by clicking and dragging the lower right corner. It can be resized to any width.

The Animation Time Line palette (a) in its default size and (b) after zooming in.

a

b

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The Animation Editor palette

This palette provides ways for graphically editing the functions that describe the motion or value changes of a track. A basic way for representing the value changes of a track is through a Bezier controller function, which contains a sequence of keyframes that describe how the value of the track changes over time. The way one keyframe transitions to the next is called interpolation. Through this palette, one can fully describe how the interpolation between Bezier keyframes occurs. In addition, other control-ler functions can be added to describe the value changes of tracks with respect to time. These additional controller functions are not necessarily based on keyframes and they may be dictated by mathematical formulas or specific data.

The Animation Editor palette.

The Bezier controlled keyframes can be edited in the same way one would manipulate control points of a curve. Editing these control points allows the user to specify how transitions happen between and beyond keyframes. One can speed up or slow down the way an entity moves toward a specified location, change how fast something is spinning, mimic the pull of gravity, or repeat something indefinitely. All these effects can be done by editing the control points of a track. In short, the position, velocity, and accelera-tion are easily editable for any type of track through the Bezier controller function.

Following are a few common notions about motion control in relation to keyframes:

• If the line between keyframes is flat horizontally, the value for that

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track is not changing. In other words, it is not “moving” and therefore has no velocity (no change in value). • If the line through two keyframes is slanted and straight, the value is changing at a linear rate, or constant velocity. • If the line through two keyframes is curved, the rate of change is no longer linear and the velocity is no longer constant, but is changing between the keyframes, due to some acceleration or deceleration. An example of this would be the motion of a tree falling due to gravity, which can be simulated with a quadratic curve.

The Animation Editor Palette is divided into the following sections:

• On the left is the Animation Score section. • On center right is the graph. Here curves for controller functions of tracks are displayed and edited. • Above the graph are tools and commands that are used for window navigation and control point manipulation. • Below the graph, the section labeled Key displays information about the currently selected and highlighted keyframe of the active controller function, such as numeric coordinates and control point types.

The Animation Score section of the Animation Editor palette consists of five columns, which display a list of all animated entities, their tracks, and controller functions. The currently highlighted item is the active one, and since certain operations apply to a single item, this is the item to which these settings are applied. To change the currently active item, either use the hierarchy list and select another editable item, or click an editable track’s control point.

Through the hierarchy list, you can control which tracks and controllers are visible and editable in the graph by turning on and off the lock icon respectively. • The first column (left to right) is the selection column. Clicking in it selects/deselects the entity. It displays a check mark ( ) when the entity is selected and no mark when it is not selected. • The second column is the visibility column. Clicking on the eye symbol ( ) makes the entity’s motion trails and keyframes visible/invisible in the model window, provided the same global settings in the Preview tab of the Animation Options dialog are enabled. This is only applicable on a per entity basis, not for individual tracks, which means that changes made to any track are applied to all the tracks of the same entity. • The third column is the lock column. It controls whether or not a track can be edited. If the lock symbol ( ) is displayed, the track is dimmed in the Animation Editor palette and cannot be keyframed.

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• The fourth column is the on/off track column. Tracks with the bullet marker ( ) on are currently being applied to the entity and are having an effect on animating it. Tracks with this off are not being applied and hence have no effect on the animation. • The fifth column is the name column. It displays the names of the graph entities, tracks, and controllers. These entries are folders and have a right pointing triangle in front of their names. Clicking on the triangle opens the folder and list its content.

The Animation Score section context menu

This dialog provides management tools for work-ing with animated entities. It can be invoked by right clicking on the title of an entity in the Name column of the Animation Editor palette.

Most of the operations available in the dialog are applied to the active listing of an animated entity, track, or coltroller. You make an entity, track, or controller active by clicking on it. Depending on what type of an item is active, some of the operations in the dialog may not apply and will be dimmed. When active, they may act differ-ently depending on whether an entity, track, or controller is currently highlighted.

New Group: Clicking on this button creates a new animation group with no animation tracks.

Add Tracks...: This button is available only when an entity or group is highlighted. Clicking on it opens the Add Tracks dialog that contains a list of all the available animation tracks for the currently active entity. Highlight one or more of the tracks from the list to add them to the active item.

The Add Tracks dialog

To invoke this dialog, right click an entity from the list in the Animation Editor palette and select Add Tracks. This dialog is used to add tracks to an animated entity. To do this, simply select the desired tracks from the list provided in the dialog and press OK. The selected tracks are added to the entity that was selected in the Animation Editor at the time the Add Tracks dialog was invoked. Depending on the type of the active entity to which the tracks are added, different types of tracks can apply. The Add Tracks dialog will only list the tracks that apply to the active entity.

The Animation Score section, context menu.

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Category: This pop up menu contains items that represent the categories of tracks that apply to the active entity. For example, if the active entity is an extruded object, the three items shown in figure (b) are contained in the pop up menu. Different categories would be contained for animated lights, views, and morphed items. The tracks displayed in the Available Track Types list change according to the item selected from the Category pop up menu.

Both the content of the Category pop up menu and of the lists of tracks are different for different types of objects. Typically, the first two categories are the Transfor-mations and the Object Attri-butes. The latter are attributes of a general character, such as Vis-ibility, Surface Style, and Casts Shadows.

The third category depends on the type of object. That is, each controlled object type has its own set of tracks. For example, different types of objects would be a Sphere, Cube, Extrusion, Helix, etc. Each of these types has its own set of tracks.

For the animated views, the categories will be View Eye/COI, which contains tracks that pertain to the positions of the eye point and center of interest of views; View Attributes, which contains tracks for parameters such as visibility, hither, and yon; and a third category that depends on the view type that may be Perspective, Axonometric, etc. These contain tracks such as Focal Length and Zoom.

Similarly, for the lights, the categories will be Light Location/COI, Light Attributes, and a light type category, which might be Cone, containing tracks such as Inner Angle.

For animated deformations, tracks that pertain to the current deformation are listed under the proper category. For example, a Shear deformation will have Upper Scale as one of its tracks.

(a) The Add Tracks dialog and (b) the Category pop up menu for an extrud-

ed object.

a

b

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For animated surface styles, categories relevant to the surface styles are contained in the pop up menu and there are categories for each type of RenderZone Plus shader.

Available Track Types: As already mentioned, this list contains the track types of the category currently displayed in the Category pop up menu. This is a list of all the tracks available to an entity, regardless of whether the entity already has a track of a particular type. Multiple track types can be selected by holding the shift key down, from the same or different categories, and they will be added to the entity at the same time.

Add Controllers...: This button is available only when a track is highlighted. Clicking on it opens the Add Controllers dialog with a list of all the available controller functions for the currently active track. Highlight one or more of the controller functions from the list to add them with default values to the active track.

The Add Controllers dialog

This dialog, shown in to the right, works in a fashion similar to the previ-ously discussed Add Tracks dialog, except that it has no Category pop up menu. All the available controllers are listed under a single category. You select one or more controllers from its list and you then press OK. The selected controllers are added to the track that was active in the Animation Editor palette at the time the Add Controllers dialog was invoked.

Graph

The curves with control points shown in the graph represent the currently editable or visible tracks. The main area of the graph is used for display and editing.

The values associated with a curve can be inferred by the horizontal and vertical axes of the graph. The horizontal time line axis is displayed across

The Add Controllers dialog.

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the top and shows the time or frame at which a value occurs. The vertical axis on the left displays values, including the actual values of the active track. Each track may have a different range of values depending on its track type. For example, a rotation track will show angular values for the value axis, whereas a path track may show either distance or percentage values.

Editable tracks are shown in their full color. Tracks that are visible but locked so that no editing can occur on them, are shown in a dimmed color. The user has control over what tracks are visible and editable in the Animation Editor palette through the hierarchical track list.

Some commands or options apply to the active track or controller function. The currently active item is highlighted in the hierarchical list. To make a track active, with the Pick tool of the Animation Editor palette selected, click on the item's name in the hierarchical track list or on a control point of an editable track.

Some commands or options apply to a single keyframe, which needs to be active. You make a keyframe active by clicking on it with the Pick tool. The currently active keyframe is indicated on the graph by a circle drawn around the control point ( ). The active keyframe’s settings are shown in the Key section.

The keyframes shown on the graph are assigned different types of control points. Each keyframe control point may have lead in and lead out con-trol points which are affected by the control point types. The control point types affect a keyframe’s tangency, whether or not it has lead in or lead out control points, or whether it has stepped behavior.

Editing control points and curves

Different editing actions can occur using one of the 15 tools found above the graph area of the Animation Editor palette. These actions generally belong in five categories, namely, picking and moving, inserting and deleting, zooming in and out, panning, and aligning. They are discussed below:

Pick: With this tool active click on a control point or a curve to select them. When using a two button mouse you click with the left button. • Clicking on an unpicked control point unpicks any previously picked control points and picks the clicked control point and any other control points that are dependent on it. • Clicking on a key control point picks the key and its lead control points. • Clicking on a lead control point picks the opposing lead control point,

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if it is tangently locked, or the other lead control point of a step. • Pressing shift while clicking allows one to pick multiple control points, adding each newly clicked point to the selection. • Clicking and dragging over an area of the graph rubber-bands a box and picks all the control points within the box. • Clicking on a curve picks the two immediately surrounding key control points. • Pressing control (Macintosh) or ctrl+alt (Windows) while clicking on the curve picks all the control points of the entire track. • Clicking on empty space unpicks any previously picked control points. • Whenever a lead control point is very near or on top of a key control point, clicking once on the two control points will select the lead control point; clicking again will select the key control point. If there are several overlapping control points, holding command (Macintosh) or ctrl (Windows) while clicking will allow one to toggle through all the potential picks near the click point.

Pick and Move: With this tool active click on a control point or curve and drag the mouse where you wish to move it. If more than one points are highlighted (picked), they all move. One can move control points of any editable track. • Once the dragging has begun, holding shift restricts movement either horizontally or vertically, depending on the distance to the nearest axis of the original click location. • One can also turn on snapping for both value and time to move control points to rounded positions.

Pick and Scale: If a curve is selected (which is equivalent to all its points being selected) and you pick the end control point while you press control (Macintosh) or ctrl+alt (Windows), you will scale all the points of the curve relative to the direction in which you drag the mouse.

Arrow keys Up, Down, Left, and Right: Nudge motion in respective direction: The arrow keys can be used to incrementally move selected control points one pixel in the respective direction. If snapping is on, the selected control point moves to the next snap location.

Note that what is displayed on the graph are tracks as functions of values with respect to time. Hence, the curve cannot have two values for the exact same time and loops or curves that turn back in time are meaning-less. Therefore, it is not allowed to create such conditions by moving a control point to a position corresponding to an earlier time than the previous control point.

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Insert Control Point: With this tool active, clicking on a curve will insert a new keyframe on the curve at the click location. Clicking away from all editable curves inserts a new keyframe for the active curve at the clicked location. If snapping is on, the newly inserted control point will be snapped to the nearest snap location. Holding control (Macintosh) or ctrl+alt (Windows) and clicking away from all editable curves inserts a new keyframe on all editable curves at the clicked location. Upon inserting once, the insert mode changes automatically to the pick mode. If you desire to stay in insert mode, hold command (Macintosh) or ctrl (Windows) while clicking.

Delete Control Point: Clicking on this tool deletes all the highlighted control points from the track curve they belong to. The same result is achieved if, instead of clicking on this tool, you press the delete key on the keyboard.

Cutting, copying, and pasting control points

Control points can also be cut, copied, and pasted using the respective menu items in the Edit menu. To cut or copy, pick any number of control points on the active track and then click on Cut or Copy in the Edit menu.

Next, you may want to paste these points on the same or another track. Before pasting, make active the track where you wish the points to be pasted, then click on Paste in the Edit menu. Before executing the past-ing, the program will invoke the Paste Control Points Options dialog, shown in the Figure to the right, where you set how the points are to be pasted.

Different track types have different types of values. Hence, copying from one track type to another does not copy the raw values of the data like in the case of copying two similar track types. Instead, the relative placement of the con-trol points to each other is copied, and placed onto the new track with respect to the values displayed in the second track’s value axes. Also integer track types cannot receive values copied from non-integer tracks.

When the first point is selected at the time you are copying and it becomes

The Paste Control Points Options dialog.

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the first point in the track to which you are copying, then the Before settings are also copied to the new track. Likewise, if the last point is selected and it becomes the last point in the track to which you are copying, the After settings are also copied to the new track.

The top of the Paste Control Points Options dialog (shown in the Figure above) contains feedback about what is about to be pasted. It describes what will be pasted and where.

Values: This option affects the values being pasted.

Paste Relative: When this option is on, the values are pasted with respect to the entity’s default value for that track. So, the Position X track’s control points of one entity could be copied and pasted on to another entity without the second entity having the exact same X values, but rather have the motion be the same relative to the second.

Time: These options affect the time values being pasted.

Remove Control Points: The options in this group determine whether existing control points will be removed and how.

None: When this option is on, none of the existing keyframes is removed.

Only Those Within Time Span: When this option is on, the con-trol points on the pasting track that are within the time span of the copied control points are removed, prior to pasting the new ones.

All: When this option is on, all existing control points are removed before pasting the new ones.

Time Span: The two options in this group define the time span of the pasted control points.

Keep Same: When this option is on, the start and end times of the newly pasted control points remain the same.

New: When this option is on, new start and end times are entered in the two numeric fields next to it. This allows you to scale the pasted control points to a desired span, or to just alter at what point in time they are pasted, or both.

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Zooming, fitting, and panning the graph

There are three methods for zooming, which are analogous to those avail-able in the main project window. They work as follows:

Zoom in, Zoom out: Clicking on these tools the graph image is zoomed in or out incrementally, without adjusting the center of the image. The operations are repeated everytime you click on the icons.

Pressing command (Macintosh) or ctrl (Windows) zooms in/out in the time axis only.

Pressing control (Macintosh) or alt (Windows) zooms in/out in the value axis only.

Fit Visible: Clicking on this icon will zoom automatically to fit all the visible tracks in the viewing area of the graph.

Fit Animation: Clicking on this icon will zoom automatically to fit all the visible tracks within their value axes and the entire animation start and end times in the horizontal axis.

Fit Picked: Clicking on this icon will zoom automatically to fit all the currently picked control points in the graph area.

Use the Lock check buttons in the Graph Options dialog, discussed later in this section to force zooming in one axis only.

Panning: With this tool active, clicking and dragging in the graph area will move the graph in the direction of the mouse movement. Panning can also be temporarily enabled when in Pick mode. With the Pick tool active, press control (Macintosh) or ctrl (Windows) while you click on the value axis or the time line and drag them vertically or horizontally, respectively.

Center Current Frame: Clicking on this tool will automatically pan so that the current frame is centered in the graph.

Use the Lock check buttons in the Graph Options dialog to force panning in one axis only.

The mouse scroll wheel can also be used to zoom in/out. Also, the middle mouse button can be used to pan the graph.

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Aligning control points

There are four methods for aligning control points and/or the lead in/out values:

Linear: This command will cause consecutively picked control points to be aligned in a straight line between the outermost selected control points (without causing the control point types to be changed to linear).

Flat: This command will cause picked keyframes’ leads to become horizontal with or equal to their key points’ values.

Align Value: This command will align all the picked keyframes hori-zontally. The currently active keyframe is used as the reference to which to align. Holding shift while clicking on this command will also align the leads to the same value.

Align Time: This command will align picked keyframes vertically, in time. Hence, this is useful for aligning keyframes of different tracks.

You can also align control points by entering a value numerically. To do this, pick all the points you desire to align and then type a numeric value in either the Time or Value field, or both in the Key section (see next subsec-tion). All picked points will take the same numeric value.

Setting the current time

If you click in the time line, the current time is set to the clicked frame. Also, in pick mode, if you hold option (Macintosh) or ctrl+shft (Windows) and click anywhere in the graph, the current time is set to the time of the frame closest to the click point.

The Key section

This section displays information related to the currently selected (active) keyframe. The active control point is noted on the graph with an additional outlining circle. There are several parameters within this section that affect the active keyframe and its leads.

Current key fields: Two alphanumeric fields (with the word of between them) are used to denote the index of the active keyframe and the total number of keyframes in the track controller. The value in the first field changes every time the active keyframe changes. Or a new value can be typed in this field to change the active keyframe. The value in the second field changes automatically when new keyframes are inserted

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or deleted.

Previous/Next keys: Clicking on these buttons changes the selected key to the previous or next key of the active track. If more than one keyframe is picked at the time these buttons are clicked, the active keyframe cycles through only the picked keys.

Time: This editable field represents the time of the current key. It changes every time the current key's position along the time axis is changed. Alternatively, the value in the field may be changed by typing another value, which will cause the current key to also move along the time axis.

Value: This editable field represents the value of the current key and behaves as the Time, except that it applies to the value axis.

Control point types: At the right end of the Keys section, there are three frames labeled Lead In, Key, and Lead Out. Each contains three icons which can be used to change the type of the active control point. The highlighted icon in each group represents the current keyframe control point type. The type of a control point affects how the curve flows through that control point. Different types produce different animation effects. For example, to simulate a bounce or rapid change in direction, tangency at the respective keyframe should be off. The available types are as follows:

Lead In

Curve In: Lead in point controls how the curve arrives at the key point.

Linear In: There is no lead in control point, so the line arrives linearly at the key point.

Step In: The lead in point controls where the step occurs.

Lock: This makes the currently selected keyframe’s lead in im-movable with respect to the key. Hence, you can still move the key, and the control point moves along with it, but you cannot move the lead in separately. If the keyframe is locked tangently, this also forces the lead out to be movable only in the tangent direction.

Key

Tangency Locked: The curve is tangent at the key point, but the lead in and out may have different distances from the key.

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Tangency Locked, Equal: The curve is tangent at the key point and the lead in and out will always have equal distances from the key. No Tangency: The key point does not enforce tangency, allowing for sharp corners. Lock: This makes the currently selected keyframe’s key control point to be immovable.

Lead Out

Curve Out: Lead out point controls how the curve leaves from the key point. Linear Out: There is no lead out control point, so the line leaves linearly from the key point. Step Out: The lead out point controls where the step occurs. Lock: This does the same thing as for the Lead In option. Note that the first and last control point of a track only has (at most) one lead control point. Therefore only certain icons are selectable when one of these key control points is the currently selected one. The meaning of the locked tangency status of these terminal points depends on the ante or post settings for the track or whether or not the track is closed. So, one can lock the tangency of the first control point with the ante behavior, the last control point with the post behavior, or lock the first and last together with the closed check box. For example, if the first keyframe is locked tangently and the ante behavior is set to constant, then the lead out control point will be forced to be horizontal with the key point, making it tangent with the constant ante behavior. In the Repeat Normal case, tangency acts like the closed case in that the first and last control points are tangent to each other.

Track Options...

This dialog can be invoked by either right clicking on a control point in the graph or by right clicking a track from the hierarchical list on the left side of the Animation Editor palette.

Before/After: The before and after behavior of the active controller function can be changed in this section. The before and after behavior of a curve affects how an entity gets its values from a track prior to the start time of the controller, and after the end time (formally called “extrapolation”). For

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example, if an entity has its first keyframe for a Position X track at frame 100, the before behavior will define what the X location is before frame 100 is reached. The difference in the options for the before and after behavior is that one is applied prior to the first keyframe and one is applied after the last keyframe.

Type: The items in this pop up menu define the before or after behavior of end keyframes.

None: When this item is selected, no behavior is defined, so the entity should use its original value. This is the default state.

Constant: When this item is selected, a line extends horizontally from the first or last key point, meaning the value is unchanging from the first or last value.

Tangent: When this item is selected, a line extends tangently from the first or last key point, mean-ing the value continues on changing linearly.

Repeat Normal: When this item is selected, the entire track is repeated.

Repeat Mirror: When this item is selected, the entire track’s keyframes are repeated in reverse order.

Has A Bound: When this option is on, the behavior stops at some predetermined time, speci-fied in the following fields.

Start Time / End Time: The former appears when Before is selected and the latter when After is selected. When this option is on, the value entered in the Start Time field determines the absolute time at which the behavior stops. The value entered in the End Time field determines the time at which the behavior starts.

Repetitions: When this option is on, the value entered in its field determines the relative number of times that the behavior should continue. The length of a repetition is the span of the keyframes.

The track options dialog

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Offset By: When this option is on, the value entered in its field deter-mines the offset of the next repetition.

Match Beginning To End: When this option is on, the values of the repeated first and last keyframes are aligned. This option is only meaningful for the Repeat Normal behavior.

Connect Beginning And End: When this option is checked, the first and the last control points of the track are forced to have the same value. Also, if either terminal point is tangently locked, then the first and last control points also share tangency.

Track Color: This box shows the color in which a track is shown in the graph. Clicking on the box invokes the standard Color Picker dialog, where the desired color can be set. Track colors are retained in the prefer-ences and apply to all tracks of the same type (i.e. changing the color of the Position X track in one entity changes it for all entities).

Show Velocity Curve: When this option is checked, this track’s velocity curve is displayed in the graph in a dimmed color. The velocity curve is the first derivative curve of the value curve. It displays how fast the value is changing as well as speed ups and slow downs and changes in direc-tions.

Options...: Clicking on this button invokes an options dialog for the currently highlighted item in the hierarchy list, if such a dialog exists. For example, an animation group has options to change its axes, a path track has op-tions for the path it is following, a sine controller has options to define its functional values. When one of these entities is highlighted, clicking on this button invokes its dialog.

Constant Velocity: Clicking on this button adjusts the velocity of the highlighted entity such that its resulting velocity is constant along its current motion trail. Sometimes after keyframing an entity's position, one would like to easily and automatically make the entity move at a constant rate along its same trail. This button recomputes the position tracks' keyframes along the same trail to achieve this result. Alternatively, one could use the Extract tool to extract the motion trail object, delete the position and rotation tracks off the entity, and use the Animate along Path tool on the entity and the extracted path object, which will result in the entity moving with constant velocity by default.

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The Graph Options... button

This button, located at the upper right portion of the Animation Editor pal-ette, invokes the Graph Options dialog, shown in the figure to the right. It contains options for controlling the look and feel of the graph and for specifying how editing is done.

Time Line Axis: The options in this group determine how the horizontal time line axis looks and works.

Lock: When this option is on, zooming and panning is restricted and the time line can not be changed.

Show Lines: With this option on, which is the default, the animation bounds and current frame line are displayed. They are not otherwise.

Snap: The options in this group determine the snapping that is in ef-fect relative to the horizontal time axis.

Axis: When this is on, snapping occurs relative to time axis values, set in the following two fields.

Seconds: The value typed in this field determines the snapping interval in seconds.

Frames: The value entered in this field determines the snapping interval in frames.

Other Points’ Times: When this option is on, snapping also occurs relative to other visible tracks’ control points.

Value Axis: The options in this group detrmine how the vertical value axis looks and works.

Lock: Works as for Time Line Axis (see above).

Show Lines: When on, extra horizontal lines are shown across the whole graph.

Snap: The options in this section set snapping for the vertical axis.

Axis: When on, snapping occurs relative to the vertical axis val-ues.

Match Axis: When this option is on, the snap values are automati-

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cally derived from the current graph’s increment values.

Custom: When this option is on, the user can type desirable values to which to snap. Different values are entered for the different types of tracks, as follows:

Distance : The value in this field sets the snap value for positional track types.

Angle: The value in this field sets the snap value for angular track types.

Percent : The value in this field sets the snap value for for percentage track types.

None: The value in this field sets the snap value for for track types without a unit.

Integer: The value in this field sets the snap value for integer track types.

Other Points’ Values: When this option is on, the control points of other visible tracks can be used as snapping values.

View Path Distance As Percent: With this option on, which is the default, a path’s value axis will be displayed as a percentage. It will be displayed as a distance along the path, otherwise.

Auto Scroll: When this option is on, when moving control points or rubber banding to frame pick multiple control points, the graph will automatically pan following the location of the mouse.

Keyframe Movement: The options in this group determine the behavior of the modeling window when control points are moved.

Update Window While Dragging: When this option is on, the model window is updated continuously while control points are being actively moved.

The Graph Options dialog.

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This option should be turned off if this kind of interactivity is not desired or the animated scene becomes too complex to work interactively.

Active Window Only: When this option is on, only the active window of the project is kept updated.

All Windows: With this option on, all project windows are kept updated. Auto Adjust Leads: When this is checked, the magnitude of the lead control points is automatically adjusted as key control points are moved.

Only When Necessary: When this is checked, the leads magni-tudes are only adjusted when necessary. For example, since a lead out can not pass the succeeding keypoint in time, the lead out magnitude will be shortened when dragging the key toward it.

Allow Dragging Past Neighbors: With this option checked, key control points can be moved past their neighboring key control points, ef-fectively swapping their order. Otherwise the neighbor key control points act as boundaries.

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Animation controller functions

The animation controller functions compute the values for every track of an animation. The default controller function for a track is the Bezier interpola-tion function. Other controller functions may be used in addition to or in-stead of the Bezier interpolation function. Animation controllers control how a track’s value changes over time, thus for each time value or frame of an animation there is a single value computed. Some controllers are based on a mathematical formula to compute their values, while others are based on an interpolation method between fixed values. A controller function in gen-eral can be built from any algorithm that results in computing a value given some input parameters (and usually time is also a parameter).

To add a controller to a track, right click a track in the Animation Editor palette and choose Add Controllers... Clicking on the triangle next to the track name will reveal what controllers are currently controlling the track’s value. By default there should be a Bezier controller. Clicking Add Control-lers... will bring up a dialog from which to choose additional controllers for the track. Controllers may also be removed from a track by right clicking that controller in the Animation Editor palette and selecting Delete.

Stacking controllers

Some controllers can be “stacked” on top of other controllers, meaning that one of their input values is the result from another controller and is used by the controller to compute a new result. The Sine and Noise controller may be stacked in this way with existing controllers. The effect of this can be seen in the following examples.

The bezier controller

This controller provides the user with a sequence of control points consist-ing of time value pairs. These control points are strung together through Bezier interpolation, which provides smooth transitions between each pair of key control points. Lead control points offer control over how fast or slow a change in value occurs, as well as controlling sharp or smooth transitions at keyframe points. The options associated with this Bezier controller func-tion are built right into the Animation Editor palette. Through the Animation Editor graph, you can easily manipulate the Bezier control points of all the animation tracks. For example, you can change the control points types there, and change the control points values graphically or numerically. Be-low is an example of an object with 6 tracks, each controlled by a Bezier controller function.

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The sine controller

This controller changes its value over time in the shape of a sine function. You may want to be able to define the motion of an object with a motion based on a sine function. This type of motion would be useful for animating pendulum motion of swinging objects, or any sort of repeating oscillating motion. You can control its parameters like amplitude, period, and time and value offsets. The figure to the right shows an example of a clock’s pendu-lum with a Sine controller for its Y rotation track.

The Sine controller can be stacked on another controller, or used by itself. Stacking it on to another motion will result in the original motion becoming wavy. For example, the original motion of an object rising and falling verti-cally can have a Sine filter added on top of it to oscillate its height while it is

The Animation Editor palette with 6 tracks controlled by a Bezier controller function.

The Animation Editor palette with a Sine controller for its Y rotation.

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The Animation Editor palette showing a Bezier controller and a Sine con-troller on the Position Z track.

rising and falling. Note that the sine controller is drawn on the graph in its pure form and also where it is having an effect on the Position Z track.

An animation with a sine filter added.

The Sine Controller Options di-alog can be invoked by right click-ing on the sine controller track from the heirarchical list and se-lecting Controller Options... in the Animation Editor palette. Its options are as follows:

Start Time: If this option is on, its value represents the time at which to begin the sine function.

End Time: If this option is on, its value represents the time at which to end the sine function.

Amplitude: This value repre-sents the magnitude to which the sine function reaches in value.

Period: This is the time of one complete oscillation.

Time Offset: This value repre-sents the amount of time to shift the sine function horizontally.

The Sine Controller Options dialog.

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Value Offset: This is the value to shift the sine function vertically.

The noise controller

This controller changes its value over time by producing a value randomly offset from the original value.

You may want to add an element of randomness or bumpiness to the motion of something you are animating. You can change the strength of the ran-domness, or its frequency. You may want to add randomness to a camera to simulate shakiness or the ground shaking. You may want to add noise to a flickering light. An example of adding noise to a moving object is shown to the right. To simulate a bumpy terrain, noise was added for its rotation tracks and position track.

The Noise Controller Options dialog can be invoked by right clicking on the noise controller track from the heirarchical list and selecting Controller

The Noise Controller Options dialog.

Options... in the Animation Editor palette. Its options are as follows:

Start Time, End Time: As for the Sine Controller Options dialog.

Strength: The value in this field represents the magnitude of the largest possible disturbance for the noise. This field is displayed using the units of the track which the controller is applied to. If the track represents a distance (i.e. position), a distance value is shown. If the track represents an angle (i.e. rotation), an angle is shown.

Frequency: The value in this field represents how often (in time) a new disturbance occurs.

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Controllers may also have tracks

Controller functions themselves may have parameters associated with them that may change with respect to time. This means that controllers can also have tracks for these parameters. These tracks in turn may be controlled by their own controllers. This nesting may go on indefinitely, though for reason-able results there usually wouldn’t be a need to nest more than a couple of levels deep.

The Animation Editor palette.

An animation with noise added to simulate bumpy terrain.

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The Animation tools

There are several tools that relate to animation and are discussed in this section. They are:

Keyframe

Animate along Path

Animate Entities

Animation Group

Animate Deformations

Extract Animation

Reverse Animation

Replace Animation

In addition to these tools, a number of common modeling tools can be used to manipulate animated entities. These are also discussed towards the end of this section.

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The Keyframe Tool

The Keyframe tool makes static entities animated and creates additional keyframes for animated entities when using the manual keyframing method. If the entity is static, it is made animated by adding tracks, adding it to the animation editor, and creating an initial keyframe for the current state at the current time. If it is animated, a keyframe of the entity in its current state is created at the current time. If a keyframe already exists at the current time, the values are updated to reflect the current state of the entity.

With the postpick method, set the current time to the desired time for the keyframe using the Animation Time Line palette, select the Keyframe tool, click on the entity (object, object point, light, view or animation group) to keyframe it. With the prepick method, use the Pick tool to select the entities to be keyframed, set the current time to the desired time for the keyframe using the Animation Time Line palette, select the Keyframe tool and click anywhere in the graphics window.

To add additional keyframes using the manual keyframing method, first disable auto keyframing by de-selecting its icon from the Animation Time Line palette. Set the current time to the desired time for the next keyframe using the Animation Time Line palette. Use the form•Z tools and interfaces to change the entities' appearance to the desired form. Use the Keyframe tool to capture the new keyframe. Repeat this process as many times as necessary to achieve the desired animation.

The Keyframe Tool Options palette contains options that control how the Keyframe tool is applied.

Create Initial Tracks: When this option is on, tracks are created when a non-

The Keyframe: Tool Options palette.

animated entity is made animated. When this is not selected, no tracks are created, however the entity is still added to the Animation Editor palette. This item is on by default. The following options are enabled when this option is on:

Default Tracks: When this option is selected, only the default tracks are created for non-animated entities.

Transformation Tracks: When this option is on, only position, rota-tion, and scale tracks are initially created for non-animated entities.

User Selected Tracks: When

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this option is on, the Add Tracks dialog is invoked that allows the user to pick which tracks will be initially added. This dialog is the same as the one invoked by right clicking an entity in the Animation Editor palette and selecting Add Tracks... from the context menu.

Separate Tracks For Views: When this option is selected, separate tracks are created for the eye point and center of interest for non-animated views. This allows for views to be keyframed by their eye point and center of interest positions instead of the standard position and orientation tracks. This option is used when the tracks are initially created and only applied when the entire view is selected. If only the eye point or the center of interest is selected, then the corresponding tracks are created.

Separate Tracks For Lights: This item functions the same as the Cre-ate Separate Tracks For Views, except for lights.

Existing Tracks: This group of options controls how existing tracks are updated when the tool is applied to an entity that is already animated.

Key All Existing: When this option is on, a key is added to the default Bezier controllers for all of the entities' tracks.

Key Changed Tracks Only: When this option is on, keys are only added to the default Bezier controllers when the parameters have changed from the current evaluated values. This prevents the accumulation of un-necessary keys. This option is on by default.

Add Missing Tracks: When this option is on, if a default track does not exist for the entity (because it has been deleted or was never previously added), the track is created and default key values are added. Otherwise only those tracks present are keyed. This option is on by default.

Maintain Adjacent Keys: When this option is on, which is the default, keys are inserted in the adjacent keyframes to maintain the current value of the entity at the adjacent keyframe's times.

Leads: This group of options control how the default lead-in and lead-out values are established for the default Bezier controller of each track. These options have subtle effects on the motion of the entity at keyframe positions.

Magnitude: The value in this field, which is a percentage, specifies the distance of the leads from their keys. This value is relative to the distance between adjacent keyframes and may be limited by the proximity of adjacent keys, as a lead cannot be located before the previous key or beyond the next key.

Keep Flat: When this option is on, the leads of an inserted key are flat. That is, they have the same value as the key and they are horizontal. This results in sharper transitions. When this option is off, the leads are positioned

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along the line between adjacent keys. This results in smoother transitions. This option is off by default.

Below are some examples with different values for the Magnitude and Keep Flat options. On the left are the graphs of the Animation Editor palette that correspond to the animated objects shown on the right. The animated object is a cube shown in top view. The cube was animated by clicking on it with the Keyframe tool at time 0. The time was then moved to 2 and 4 seconds in the Animation Time Line palette, and the cube was moved to the shown positions, using the Move tool. The Show At Interval option is turned on in the Anima-tion Options dialog and 0.25 has been entered in its field. This displays the in-between frames every 0.25 seconds, which makes it easier to follow the effects of the options we use. Also, observe the positions of the white circles (leads) in the Animation Editor palette graphs.

Animating points, segments, outlines, and faces

Keyframe animation using Magnitude and Keep Flat set to: (a) 15% and off; (b) 85% and off; (c) 85% and on.

a

b

c

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and smooth objects can be animated, using the Keyframe tool, which is sensitive to the active topological level. That is, when the tool is used in either postpick or prepick mode and Points, Segments, Outlines, or Faces are selected, the selected object part becomes animated. When an object’s part becomes animated, the object itself also becomes animated; hence the object is automatically added to the list in the Animation Editor palette, if it is not already in-cluded. The animated part appears nested in the object's group

An example of an animated point is shown below . Segments, outlines, and faces can be animated in a similar fashion.

The Animation Editor palette listing an animated point, segment, and

face of three seperate objects.

Animating a point: (a) The pyramid and its apex are animated by setting time to 0 and with the Keyframe tool active, holding Cmd (Macintosh), Ctrl (Win-dows) to click on the apex point. (b) After moving the time to n seconds, the apex point is moved up vertically. (c) Playing the animation and stopping it halfway. Shown are the keyframes and the animated object. (d) As in c with

the keyframes turned off.

In addition to animating objects and their parameters, entities at lower topo-logical levels, namely points, segments, outlines, and faces of both facetted

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Animate Along Path

The Animate Along Path tool makes static entities animated such that they follow a path defined by an object. When the tool is applied, a path track is added to the entity. This track defines the position of the entity along the path. By default the entities travel the entire course of the path from its start to its end. Two keyframes are added initially to the default Bezier controller of the path track. The first key has a value of 0% and indicates that the entity is at the start of the path. The second key has a value of 100% and indicates that the entity has moved the full path’s distance. The key values can be changed using the animation editor.

The path object can be any object. However, the type of the object has an important effect on how it is used as a path. The most common types of paths are splines, nurbs curves, or any open or closed wire objects. In these cases the object moves along the length of the line path. When any other type of object is used, the centroid of the object is used as the path. Since the centroid is a single point, it does not define a change in position or orientation. This is useful for views or lights that have center of inter-est or eye paths, where it is useful to have them reference or “look at” an object. The path object can itself be animated so that the entity would be following a moving object.

The path object needs to be constructed before using the Animate along Path tool. The tool can be used in the prepick or postpick method, however the path object is always selected in the postpick method. With the post-pick method, select the Animate along Path tool, then click on the entity to animate and on the path object. With the prepick method, use the Pick tool to select the entities to be animated, activate the Animate along Path tool and click on the path object. When using the prepick method all of the selected entities are animated along the path object.

Entities animated along a path object are “linked” to the path. The path object remains a normal part of the project and can be edited as it could before the operation. When the path is changed, the animated entities will follow the edited shape. If the path object is deleted, the linked entities become static. The path object can be made invisible without affecting the animated entities.

Views can have a path track for the entire view or separate paths for the center of interest and the eye point. The type of tracks that are created depends on what part of the view is picked. If the entire view is picked, then a single track is created. If only the center of interest or the eye point is picked, then the corresponding track is created. To set a path for the center of interest and also for the eye point, the tool should be used once with the center of interest selected and one more time with the eye point selected.

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Direct, cone, and projector lights that have an orientation direction work as the views do. That is, they can have path tracks for the entire light or separate paths for the center of interest and origin.

The Animate Along Path: Tool Options are available when the tool is selected and contains options that control its operation.

When making an entity follow a path, there are a few options that can be set for how the entity follows the path. These options can be changed later in the Animation Editor palette (double clicking on the "Path Distance" track name).

Align To Path: When selected, in addition to following the path, the entity is aligned or orientated to the path. Aligning the local axes of the animated entity to the path object controls the orientation of the entity. There are three implicit axes along the path object. The tangent axis is the tangent to the path along the direction being traveled. For example in a car traveling along a road, the car is the animated object, the road is the path and the direction that the car is traveling is its tangent direction (straight ahead).

The Animation Along Path: Tool Op-tions palette.

The secondary axis is the perpen-dicular direction to the path. In the car example, this is the direction to the left of the car (perpendicular to the road's direction). The third axis is the Up direction and perpendicular to the plane defined by the first two axes. In the car example, this is the direction up to the sky (perpendicular to the road). The three menus Tan-gent, Secondary and Up specify which axis of the entity is aligned to the corresponding axis of the path. Note that these menus are all linked together and changing one may change another.

Keep On Top Of Path: When the entity follows the path, it will try to keep its up axis pointing upward, even when climbing inclines. This is normally what is expected when following a path.

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(a) Original objects for Animate along Path operations. Align To Path: Tan-gent, Secondary, and Up set to: (b) +x, +y, +z; (c) -x, -y, +z; (d) +y, +x, -z; (e)

+z, +x, +y.

a

b

c

d

e

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Animation along Path with (a) Keep On Top Of Path on and (b) Follow Path's Curvature on.

Follow Path’s Curvature: The up axis is aligned to the path's curvature, which may tip and turn. The path's curvature vectors are defined for every point along a curve. Each curvature vector points inward in the direction of the inscrib-ing circle's center at each point along the curve.

Create Bank Track: If checked, this option will add a special track to the path track that will cause it to automatically rotate about its tangent axis when it approaches turns in the path. The more a path curves the more the

a b

object will bank by leaning in to or away from the curve. This could simulate an aircraft as it leans in to a curve, or an object being thrown away from the curve. The bank track, by default, has one keyframe with a value of 50%. One can increase the amount of banking power the bank track has to affect the entity by editing the curve of the track in the Animation Editor. Positive values will cause the entity to “lean in” to the curve while negative values will cause the entity to “lean away” from the curve. Banking values of 0% mean the entity does not lean at turns in the curve.

Unaligned: When this option is on, the entity follows the path, without being oriented to the path. Its location simply moves along the path.

Create Standard Path Track: When this option is on, a single track is added, which controls the distance along the path.

Create Separate Path Tracks: When this option is on, independent X, Y, and Z distance tracks may be added, by turning on the respective item

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Animations along path with Align To Path: Keep On Top Of Path and Create Bank Track set to (a) on and off, (b) on and on at 50%, (c) on and on at -50%,

and (d) off and off (Unaligned on).

a

b

c

Animations along path using: (a) Align To Path: Keep On Top Of Path on and Create Bank Track off. (b)

Unaligned and Create Standard Path Track on, (c) Unaligned and Create Separate Path Tracks: X and Y on.

a

b

c

d

under it. This allows you to have different curves for each track.

Start: The entity is positioned at the start of the path at the time specified in this field.

Duration: This field determines the length of the animation from start to end.

End: This field specifies the time at which the entity is positioned at the end of the path.

Velocity: This field can be used to control the speed at which the animation is played. Changing this setting will affect the duration of the animation and

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The velocity settings in the tool options

pallete.

can be viewed in 3 separate measurements, inches per second, feet per second, and miles per hour. There is also a dropdown containing preset speeds for you to choose from, shown to the right.

Animating points, segments, outlines, and faces

As for the Keyframe tool, the Animate along Path tool can also be used to animate parts of objects and is sensitive to the active topological level. That is, when the tool is used in either the postpick or prepick mode at the Point, Segment, Outline, or Face level, the selected object part becomes animated.

a b c d

Animations along path using Unaligned: (a) Original object (cube) and an arc path. (b) With the Animate along Path tool, selecting the top face and the path, makes the cube animated and displays its two keyframes. (c)

Playing and stopping the animation at about 1/3 of total time. (d) Playing and stopping the animation again at about 2/3 of total time.

An example of a face being animated along a path is shown below.

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Animate EntitiesThis tool creates a single animated entity from a series of objects, views, lights, or animation groups. Each static entity in the series is used to define a keyframe of the animated entity.

When creating an animated view, the original views must be of the same type. Other parameters of the view can be different (spin for example). The different values will be represented in the keyframes. When creating an animated light, the original lights must be of the same type, but other parameters may be different (as with views). When creating an animated object and the picked objects are of different types, the first object's type will be used. Plain objects must also be geometrically and topologically similar, but may have different attributes and parameters.

Before using the tool, create the desired entities and edit their positions and parameters. It is recommended that the entities be created by making copies to be sure that they are all of the same type. The tool is then applied using the prepick selection method. With the Pick tool active, select at least two entities (object, lights, views, or animated groups), then activate the Animate Entities tool and click anywhere in the graphics window.

No dialog can be invoked directly from this tool, however a dialog is presented after the click with the Animate Entities tool. Depending on what type of entities have been selected, one of four variations of a dialog is invoked, namely: the Animate Object Options dialog, when objects are selected; the Animate View Options dialog, when views are selected; the Animate Light Options dialog, when lights are selected; and the Animate Group Options dialog, when animation groups are selected. Some of the options in these dialogs are common and some are unique to specific dialogs, as follows:

The Animate Object Options dialog

Origin: This group contains the remaining options of the dialog, all of which relate to the object to be animated, which occurs through its origin.

Time: This group of options determines when in the animation period the entity will be animated.

First Keyframe At: The value entered in this field determines the time of the first keyframe.

Last Keyframe At: This value determines the time of the last keyframe.

Close Path: When this option is selected, the path object will be a closed

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curve, otherwise an extra keyframe will be added such that the animated entity returns to the first keyframe.

Create Standard Tracks: When this option is on, the standard trans-formation tracks for the object are created, instead of a path track.

Create Path Track: This option will create a path track (instead of X, Y, Z tracks), to control the entity’s position. The path will pass through all the originally selected objects.

Path Type: Path tracks can be of different types. The Animate Object Options dialog.

Spline: When this option is selected, a spline object is created for the path track.

Line: When this option is selected, a vector line object is cre-ated for the path track.

Point: When this option is selected, a point is used for the path. In this case, a path track is not actually needed, so it will not be added to the entity by default. If desired, it can be added with the following option.

Construct Point Object: Select this option to explicitly add a new point object to the project and use it for the path track.

Keyframe Placement: This item determines how to place keyframes in time along the path.

Keyframes With Constant Velocity Along Path: When this item is selected, keyframes will be placed for the path track such that the new entity moves at a constant velocity over the entire path.

Keyframes At Equal Time Intervals: Keyframes will be spaced equally in time between the start and end time.

The Animate View Options and Animate Light Options dialogs

a b c

(a) Original objects for Animate Entities operations, using Create Path Track: Spline and Close Path (b) off and (d) on.

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The Animated View Options dialog.

The Animate View Options dialog is shown below. The Animate Light Options dialog is not shown as it is identical to the former except that one of its sections is labeled Location rather than Eye (see below).

Create Standard Tracks: When this option is on, the standard transforma-tion tracks for the view or light are created, treating the entity as a whole, rather than separating the eye or the location and the center of interest.

Time, First Keyframe At, Last Keyframe At, Close Path: As for the Animated Object Options dialog.

Create Separate Tracks: When this option is on, separate tracks are cre-ated for the eye or location and the center of interest.

Eye/Location or Center Of Interest: The Animated View Options and Animated Light Options dialogs contain two main sections whose content is identical, except for their titles. They are labeled Eye and Center Of Interest for the views and Location and Center Of Interest for the lights. The options in both are as follows:

Time, First Keyframe At, Last Keyframe At: As for the Animated Object Options dialog.

Close Path: If Create Path Track is selected, the path object will be a closed curve, otherwise an extra keyframe will be added such that the animated entity returns to the first keyframe.

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Create Position Tracks: When this option is on, separate X, Y, Z tracks will be created for the new entity’s position, instead of path tracks.

Create Path Track: When this option is on, one path track will be created to control the entity’s position. The path will pass through all the originally selected eye/location or center of interest points.

Path Type: Path tracks can be of different types.

Spline: When this option is on, a spline object is created for the path track.

Line: When this option is on, a vector line object is created for the path track.

Point: When this option is selected, a point is used for the path. In this case, a path track is not actually needed, so it will not be added to the entity by default. If desired, it can be added with the following option.

Construct Point Object: Select this option to explicitly add a new point object to the project and use it for the path track.

Keyframe Placement: The options in this group are as for the Animated Object Options dialog.

For newly animated objects, rotation tracks will also be added such that the entity’s rotation is keyframed in alignment with the previously positioned copies of the object.

(a) Original lights for applying the Animate Entities tool. (b) Create Path Track on; Location: Spline with Close Path off; Center Of Interest: Spline with

Close Path on.

a b

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Animation Group

This tool is used to create an animation group. Animation groups are useful for animating a collection of entities as a single transforming entity. They are also useful for hierarchically linking coordinate systems to make com-plex motions with simple parent-child relationships. An animation group has its own axis (origin and orientation) as does an individual object. The axis defines the local reference system for the group including its origin and rotation. All the children entities of a group are transformed within the group's coordinate system.

This tool can be used to form groups that include existing static or ani-mated entities. It can also be used to create empty groups. Once groups are created, they can be managed using the Animation Editor palette. The transformation tools can be used to change the position, rotation, and scale of the group.

This tool is typically used with the prepick method. Use the Pick tool to select the entities to be grouped, select the Animation Group tool, and click in the project window. The click location is significant when the Click Point option is on in the Animation Group: Tool Options palette (see below). The equivalent to the postpick method can be used to create an empty group. That is, with the Animation Group tool active (and no entities prepicked), clicking on the project window creates an empty animation group. Such groups are useful as entities can be moved into them at a later time.

The Animation Group: Tool Options palette, shown to the right, is available when the Animation Group tool is selected.

The Animation Group: Tool Options palette.

Group Axes From: This group of op-tions determines how the local axes for the group are established.

Click Point: With this option on, the new group’s origin is at the click point and the active reference plane establishes the orientation.

World Axes: When this option is on, the new group’s axes are the same as the world axes.

Active Reference Plane: When this option is selected, the new group’s axes will be the same as the active reference plane’s axes.

First Picked: When this option is selected, the new group’s axes are the same as the local axis of the entity picked first.

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A ball is animated to bounce up and down, then it is grouped with a truck. The animation group is automatically animated and a position track is gener-ated for it, with two keyframes that cause the group to travel. The truck and

the ball travel together while the ball also bounces on the truck's trunk.

Average: When this option is selected, the new group’s origin will be the average location of all the picked entities’ origins. The orientation is derived from the first picked entity.

Center Of Bounding Volume: When this item is selected, the new group’s origin will be the center of the bounding volume of all the picked entities. The orientation is derived from the first picked entity.

Note that the last three options do not work when using the postpick method to create an empty group. If one of these options is selected and no entities are selected, the click point option is used.

Examples are shown below.

The moon (a) moves around the earth (b) after being animated along the orbit path (c). These three objects are grouped and the group is animated

along path (e), which is the orbit of the earth around the sun.

a

bc

de

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Creating and querying animation groups

The Query Animation Group dialog.

Contents: Displays the number of each type of child in the animation group.

Group Transformation: This section is for editing the origin and orientation of an animation group’s axes. When you edit the group’s origin and rotation, note that all the children within the group will transform with the group. If this is not desirable, use the Edit Group Axes... button described below.

Origin: The X, Y, Z location of the group’s origin within its parent’s coordinate system.

Rotation: The X, Y, Z rotation values of the group’s axes relative to its parent’s coordinate system.

Edit Group Axes...: This button invokes the Animation Group Axes dialog.

Within the Animation Group Axes dialog you can edit an animation group’s axes, but keep all its children in their same apparent locations. That is, the group’s axes change, but the children’s axes are updated with respect the group’s new location.

Origin, Rotation: Same as for the Query Animation Group dialog, except that children are adjusted with respect to the new location and orientation

Clicking on the plus symbol ( ) above the animation score section of the Animation Editor palette creates an empty animation group. Dragging entites from the Objects, Lights, Views, Animation Editor, or Materials palettes onto the name of the group makes them members of the group.

Double clicking on an animation group brings up its Query Animation Group dialog, shown to the right. Its options are as follows:

Name: Editable name of the anima-tion group.

Owner: Name of the parent group of this group.

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(a) The Animation Group Axes dialog and (b) its Reset To pop up

menu.

a

b

so that their animated locations are the same as before.

Reset: Clicking on this button resets the rotation values to 0 degrees.

Reset To: This pop up menu resets an animation group’s axes relative to its children in one of the ways repre-sented by its items, as follows:

World Origin: The group’s axes are set to match its parent’s origin.

Active Reference Plane Origin: The group’s axes are set to match the active reference plane’s origin.

First Child’s Origin: The group’s axes are set to match the origin of the child listed first in the group.

Average All Children’s Origins: The group’s origin is set to the aver-age of all the children’s origins. The orientation is unchanged.

Center Of Bounding Volume Of All Children: The group’s origin is set to the center of the bounding volume of all the children. The orientation is unchanged.

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Animation deformationsAnimation Deformations reshape an object or group of objects over time based on a deformation method. Animation deformations share the same methods found in the Point Disturb, modeling deformation tools, and the deformation control object they create. It is highly recommended that the modeling deformations section be read prior to this section. The notable difference between modeling deformations and animation deformations is that the deformation information is retained in an animation node rather than in the object's deformation list. This allows for the deformation parameters to be animated and for multiple objects to share the same deformations. Animation deformations are a process that is applied in the animation evalu-ation and do not make permanent changes to the original object. That is, the original object's parameters are retained but the object appears deformed. This enables the animation of the object’s parameters and a deformation simultaneously. For example, an extruded object can simultaneously have its height animated and have an animated twist applied.

Animation Deformations appear as groups in the Animation Editor palette as with other animated entities (objects, lights, groups etc.). Objects that are placed in a deformation group are deformed by its deformation parameters. Objects can be added to a deformation group through the Animation De-formation tools or by dragging the object into the deformation group in the Animation Editor palette. The parameters that control the deforma-tions vary, depending on the defor-mation method. The parameters are represented by corresponding tracks for each parameter.

Most deformations are based on a reference plane referred to as the base plane and an axis which is usually the line perpendicular to the base plane, through the origin of the plane.

An Animation Deformation can be applied to the objects in the deforma-tion group individually or collectively. When applied individually, the defor-mation parameters are applied to each object using the object’s coordinate system defined by its axes. That is, the X and Y directions of the local axis define the deformation base plane

The Animation Editor palette with bulge object and bulge cage defor-

mation groups.

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and the Z axis is the deformation axis. The deformation box is the extents (bounding box) of the object relative to the base plane and axis. This type of group is referred to as a deformation object group.

When applied collectively, the base plane, axis, and box for the deformation are defined explicitly in the deformation group. This is referred to as the deformation cage. The cage is defined when a deformation group is cre-ated. The parameters of the cage can be edited and animated. The explicit definition of the deformation cage makes this method useful even when ap-plied to a single object, as it gives much more control over the deformation and allows effects that can not be created with the implicit method. This type of group is referred to as a deformation cage group.

Once created, deformation groups can be placed inside of each other to create nested deformations. Deformations can be re-grouped in the standard

Animated bulge deformation applied to two extruded objects using (a) a deformation object group and (b) a deformation cage group.

Simultaneous taper and bulge deformations applied to an object: (a) Stages of the animation with the Bulge Anchor Scale X track increasing in

value and the Taper Lower Scale Y track decreasing in value. (b) The palette showing the Taper nested inside the Bulge.

a

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fashion by dragging a deformation in or out of another deformation group in the Animation Editor palette. This allows for an object to be simultane-ously animated with multiple deformations.

Animated Deform Tools

Shear Linear Wave

Taper Circular Wave

Twist Disturb Points

Bulge Disturb Normals

Radial Shear Spread

Radial Bend

Common Deformation Parameters in the Tool Options palette.

These tools automatically create a deformation group in the animation score. The type of deformation is determined by the tool picked, and the options for each is controlled in the Tool Options palette for that tool. The Animate Shear tool options palette is shown at right. This tool may be applied in either prepick or postpick mode. In postpick mode, with the tool active, click on an object. The deformation group is added to the animation score and the selected object is placed into the deformation group. You can also click anywhere in the modeling window that does not contain a selectable object. This will create the deformation group without any objects in it.

When using the prepick mode, all of the multiple objects can be added to the deformation group. The multiple desired objects are selected first using the Pick tool, then, with the Animation Deforma-tion tool active, click in the modeling window. The deformation group

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is created and all of the prepicked objects are added to the group. Model Type: This group determines the type of model that is cre-ated from the deformation operation. Both facetted and smooth ob-jects can be deformed and each type will result in different effects. Maintain: When this option is selected, the result object will be the same type as the original object's type. This is the default. Facetted: When this option is on and a smooth object is picked, the smooth object will be converted to a facetted object. It is often useful to use this option for explorations, until the desired results are achieved, before switching to the Smooth option, which is computationally more intensive. Smooth: When this option is on and a facetted object is picked, the ob-ject will be converted to a smooth object. This does not work well when the original object has a dense mesh, because smooth deformations are computationally intensive and work best on objects with lower face Facetted Options: This group applies when facetted objects are de-formed. Note that there are no analogous options for smooth objects. Mesh: This checkbox determines whether or not the object will have a mesh created for it as it is being deformed. If this box is checked, meshing takes place and then its density can be controlled by the slider below. The farther to the right the slider is moved, the higher the density of the mesh will be. The resulting animation will show smoother surfaces during the deform. Triangulate: When this option is on, the non-planat faces of facetted ob-jects are triangulated.

Split Faces At Limits: When this option is selected, the faces of the source object are split along a new edge that corresponds to the limits of the deforma-tion. This is option is necessary when deforming an object with only a few large faces. If the source object is of sufficient density of faces, this option may be disabled and the source object will retain the same number of faces after the operation. It is often desirable to use this option when animating deformations as the original objects topology is preserved. This option is on by default. Position: This determines where the active deformation is located. As in deforming an object normally (not animating), the control for graphically set-ting the deform parameter value would be appear in this location. In the case of animation, it is simply used by the tool when it applies the deformation.

Base Reference Plane: This option allows you to specify the reference

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plane that will be used as the base plane for the deformation. Note that if the Object (XY), Object (YX), or Object(XZ) options are selected and no objects are picked, then the XY, YZ, or ZX options are used instead. Create Object Group: When this option is selected, the deformation group is created as an object group. That is, the deformation is applied to the objects in the deformation group individually as described above. Create Cage Group: When this option is selected, the deformation group is created as a cage group. That is, the deformation is applied collectively to all the objects in the deformation group using a common axis. If no objects are selected, the origin for the cage is the click point. The extents of the cage are determined by the Min and Max values in X, Y and Z, as specified in this group. Extents From Selected Objects: When this option is enabled, the combined extents (bounding box) of all of the selected ob-jects is used as the cage. When this option is off or there are no objects selected, the above Min and Max parameters are used. Origin From Selected Objects: When this option is enabled, the origin of the deformation group is established from the aver-age of the origins of the selected objects. When this option is off, or no objects are selected, the origin point is the click point. Add All Tracks: When selected, all available tracks for the ac-tive deformation method are added to the new deformation group. User Selected Tracks: When this option is selected, the Add Tracks dialog is presented for the user to select which tracks of the deformation should be added. The tracks listed in the dialog will vary depending on the deforma-tion method being used.

a

d

b

c

Deformation Cage group examples: (a) original pyramids, (b) Extents From Objects on and Origin From Objects on, (c) Extents From Objects on and

Click Point (d) Extents From Objects off and click point.

a

d

b

c

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The Query Deformation Group Parameters Tab

The Query Deformation Group dialog

This dialog provides information about a deformation group and access to the group's parameters. This dialog is accessed by double clicking on a deformation in the Animation Score palette, or by selecting the Controller Options... item from the Score palette's contextual menu, or from the Op-tions... button in the Animation Manager dialog. Deformation Group Information: This section of the dialog contains information about the deformation group. Name: The name of the deforma-tion group. The name can not be changed. The name is the name of the deformation method followed by either (Object) or (Cage) to distinguish the two types of defor-mation groups. Parent/Owner: This is the name of the group in which the group being queried resides. If it is not in a group, then this field will read None. Contents: This group contains statistical information about the contents of the deformation group including the number of Groups, Objects, Deformations, and Tracks. Parameters: This tab displays the parameters of the deformation. The contents of this area varies The Query Deformation Group

Type Tab

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depending on the type of the active deformation, as each deformation has its own specific parameters. Most of the parameters can be ed-ited relative to the deformation box (percentage) or in their real world dimensional coordinates. These parameters have a slider with a percentage text field to the right, followed by a numeric text field. The slider and text fields are all linked to the same parameter. This allows the percentage slider to be used when the actual dimension is less important and experimentation is desired. The dimensional text field can be used when accuracy is desired. Group And Box: This tab is only available for deformation cage groups. It contains items that de-fine the group transformation and box for the cage deformation. The

The Query Deformation Group Display Resolution Tab

contents of this tab are the same for all deformation types. Group Transformation: This sections defines the axis used to define the coordinate system or reference plane for the deformation. These values are initially derived from the Base Reference Plane option in the Ani-mate Deformation Options dialog. Box: This group contains the parameters for the deformation cage. The deformation box is defined by the Min and Max values in X, Y and Z di-mensions. These values are relative to the coordinate system (reference plane) defined by the above Group Transformation. Base Reference Plane: This menu is only available for object groups. It displays the reference plane used for the object deformation.

Model Type: This tab displays the resultant geometry type that will be used for the deformation.

Display Resolution: This tab displays the standard display parameters for smooth objects. The values in this tab are only used for smooth ob-jects.

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The Extract Animation: Tool Op-tions palette, shown to the right, is available when the Extract Anima-tion tool is selected.

Extract At Interval: When this option is checked, a static entity is extracted from the animated entity according to the given time interval.

Extract Animation

This tool is used to create static entities from animated entities (objects, lights, or views) by extracting states of the animated entity. These new static entities are added to the project databases for objects, lights, and views. For example, the motion trail of an animated entity can be extracted and made into a curve object. Additionally, snap shots of where the animated entity is at various frames of the animation could all be extracted and constructed as separate static entities.

To extract with the prepick method, use the Pick tool to select the desired animated entities. Then with the Extract Animation tool active, click any-where in the graphics window. To extract with the postpick method, activate the Extract Animation tool and click on an animated entity.

The Extract Animation: Tool Options palette.

Start Time: The value in this field determines the time at which to begin extracting from the animated entity.

End Time: The value in this field determines the time at which to stop extracting from the animated entity.

Interval: The value in this field specifies the time interval between each extracted entity. For example, if 1 is entered, a static entity will be extracted for every frame of the animation. If 10 is entered, a static entity will be extracted every 10 frames, etc.

Extract At Keyframes: When this option is on, a static entity is extracted from the animated entity for each time value that a keyframe occurs for that entity.

Extract Trail: When this option is on, a new static curve object is created that precisely matches the animated entity’s motion trail.

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a c

b d

a b c

The Extract Animation tool. (a) The original animation. Using (b) Extract At Interval, (c) Extract At Keyframes, and (d) Extract Trail.

The Extract Animation tool. (a) The original animation. Using Extract At Interval and shown in (b) wire frame and (c) hidden line.

Examples are shown below.

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Reverse Animation

This tool is used to reverse in time all the animation parameters associated with an animated entity. The starting and end positions are swapped in time so that the animation starts at the end position and ends at the original start position. All the keyframes between the start and end are swapped proportionally to their time position between the start and end. An example is shown below.

With the postpick method, select the Reverse Animation tool and click on the animated entity to reverse it. With the prepick method, use the Pick tool to select the entities to be reversed, select the Reverse Animation tool and click anywhere in the graphics window. Note that, when reversing an animated group, the entities within the group are not reversed unless they are explicitly picked as well. This allows for the group parameters to be reversed without affecting the entities in the group.

Reversing an animation: (a) Original animation and (b) after it has been reversed.

a

b

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Replace Animation

The Replace Animation tool allows the user to replace the animation of one or more entities with the animation of another entity. This is a complemen-tary tool to the Replace tool which replaces objects. The entity that will be replacing is referred to as source. The entity being replaced is referred to as the destination. Either the destination or the source may be non-animated (static) entities. This operation is particularly useful when multiple entities need to have the same or similar motion applied to them. The animation can be developed on one entity and then easily applied to other entities. The operation can be applied to objects, lights, views (cameras) and animation groups. When the replacement is applied to different entity types, only the common tracks are replaced.

This tool may be applied in either prepick or postpick mode. In postpick mode, with the tool active, you first click on the source and then on the destination. The operation is executed immediately and the source replaces the destination animation information. When using the prepick mode, more than one entity can be replaced with one operation. The multiple destina-tion entities are selected first using the Pick tool, then, with the Replace Animation tool active, you click on the source entity. The animation of all prepicked entities are replaced with the animation of the source entity.

The Replace Animation tool is affected by settings selected from the Replace Animation Tool Options palette that is available with the tool selected.

The Replace Animation tool: (a) An animated object and a static geodesic spheroid. (b) The static state of the spheroid is replaced with the animation

from the cube by selecting the cube and then the spheroid.

a b

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Maintain Destination: When this option is selected, the destination entity remains in its present loca-tion. When the option is disabled, the destination object is moved to the source entity's location. When this option is enabled and the source entity follows a path, the path object is copied. The options inside this group affect the operation when this option is enabled.

Position: When this option is selected, the destination entity's position is maintained but not its ro-tation. This keeps the animation trail parallel between the source and the destination, however, the destination entity may be rotated to maintain the animation alignment. This option is on by default.

Position And Rotation: When this option is selected, the destination entity's position and its rotation are maintained. This keeps the destina-tion entity intact, however, the trail of the animation of the destination object may not be parallel to the source.

Relative To: This group deter-mines what frame to use to align the replaced tracks. When First Frame is selected, which is the default, the location at the first frame of the source animation is used. When Current

The Replace Animation Options dialog.

Replacing animation from an ani-mated cube to a static pyramid: (a)

Original objects. With Maintain Destination (b) on and (c) off.

a

b

c

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Replacing animation from an animated cube to a static pyramid: (a) Origi-nal objects. (b) With First Frame on and (c) with Current Frame on (and set

to the middle keyframe).

a b c

Replacing animation from an animated cube to a static pyramid: (a) Origi-nal objects. (b) With Position on and (c) with Position And Rotation on.

a b c

Frame is selected, the location at the current frame of the animation is used. Recall that the current frame is set in the Animation Time Line palette.

Replace All Tracks: When selected all of the tracks from the source that can be applied are transferred from the source to the destination. When this is disabled, only transformation tracks (position, rotation, and scale) are replaced. This option is on by default.

Ignore Static Tracks: When this option is selected, only tracks that change over time are copied. That is, tracks with only one or no keys, or tracks where all of the keys have the same value are not transferred. This option is off by default.

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Replacing between different types

When the replacement is applied to different entity types, only the com-mon parameters are replaced. For example when replacing the animation of a light with the animation of an extrusion, only the position information is retained. The eye point and center of interest for cameras and lights can be used as either a source or destination, as shown below.

Replacing an animation from an animated cube to a light: (a) Original enti-ties. The animation of the object applied to (b) the entire light and (c) the

light's origin point only.

a b c

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Using common modeling tools on animatedentities

There are two methods for using common form•Z modeling tools to operate on animated entities and their parameters at specific keyframes. The first method is to operate on the animated entity itself, at some point in time

Using modeling tools on an ani-mated extrusion with the current

time set to the middle keyframe: (a) Original animated object. (b) Using the Edit Controls tool the height is changed, which affects this key-frame only. (c) The Height track is removed and the height is edited again with the Edit Controls tool,

which changes the height through-out the animation. (d) A new edge

is inserted with the Insert Segment tool and moved with the Move tool, which again has an effect through-

out the animation.

a

b

c

d

during the animation process. The second is to operate on a graphic representation of a keyframe.

Operating on an animated entity

When stopping the animation at a certain time in the Animation Time Line palette, the animated object freezes at that position and can be edited and changed. For example, it can be moved, rotated, or operated on in some other way. When this hap-pens and Auto Keyframe is on, the changes are automatically applied to the animation and can be observed as soon as the animation is run. If Auto Keyframe is off, the changes are not applied automatically but can be captured using the Keyframe tool, after a modeling tool has been used. If changes are made to non-animated information, the entire animated en-tity is updated to reflect the change. All modeling tools that make changes to existing objects can be used with this method.

Examples of operating on an ani-mated object are shown to the right. Given the animated cube (shown in a), it is stopped at the middle frame and this is where it will be operated on. The first operation (shown in b) adjusts its height. When the animation is run again, the cube's height will shrink between the 2nd and 3rd keyframes and it will grow again to full height between the 3rd and 4th keyframes. In other words, this operation has a local effect. In contrast, the next two operations (shown in c and d)

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have a global effect.

Operating on keyframes

The second technique is to apply a modeling tool directly to the graphic representation of a keyframe. However, only certain modeling tools can have an effect when applied to keyframes. These are discussed below.

This technique is only available when the graphic representations of keyframes are visible in the modeling window, which occurs when the Show Keyframes option is on in the Animation Options palette and visibility is turned on in the 2nd column of the Animation Editor palette for the respective entity. By default these options are on. The following tools can be used on keyframes:

Pick

The Pick tool can be used to select a keyframe by clicking with the cursor positioned on the graphic representation of the keyframe in the modeling window.

Picking a keyframe in the modeling window has the same effect as select-ing all the key values at the time of the keyframe, in the Animation Editor palette. Clicking on an animation trail (the line between keyframes) selects the keyframes at both ends of the section of the trail where the mouse is positioned when the click occurs. Selected keyframes are indicated in the Keyframe Highlight color, which is controlled by the corresponding op-tion in the Project Settings: Appearance tab and is invoked from the File menu. When two adjacent keyframes are selected and the animation trail is visible, the trail is also shown in the keyframe highlight color.

Move, Rotate, Independent Scale,

Uniform Scale, Mirror, Transform

The geometric transformation tools Move, Rotate, Independent Scale, Uniform Scale, Mirror, and Transform all can be used to directly trans-form a keyframe. When the postpick method is used, with the desired transformation tool active, you click on the desired keyframe. With the prepick method, any number of keyframes can be picked using the Pick tool, followed by the selection of the Transformation tool with which you click anywhere in the project window. The transformation is applied to all the preselected keyframes.

Delete

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Applying modeling tools to key-frames. (a) Original animated object

(extrusion). (b) Moving the 2nd keyframe with the Move tool.

(c) Rotating the fourth keyframe. (d) Deleting the middle keyframe.

a

b

c

d

Using the Transform tool on the last keyframe. (a) Original animated ob-ject. Moving the keyframe with Auto Keyframe and Transform Animation Tracks set to: (b) on and off, (c) off

and off, and (d) on and on.

a

b

c

d

The Delete tool can be used to delete keyframes. When the postpick method is used, with the Delete tool active, click on the desired keyframe. When the prepick method is used, with the Pick tool, preselect any number of keyframes, then activate the Delete tool and click anywhere in the project window. All the preselected entities are deleted immediately.

The range of the Transform tool

Recall that the Transform tool can be used to apply different geometric transformations to an object. It can also be applied to keyframes but can have a different range of effects, depending on the status of two options: the Auto Keyframe button, which is set in the Animation Time Line palette, and the Transform Animation Tracks option, which is located in the Tool Options palette.

By default, transformations on animated entities are applied to the entity in its current state for the current time. If the Auto Keyframe option is on, the transformation is applied to the keyframe at the current time. When Transform Animation Tracks is on, the transformation is applied to the entire animation sequence by transforming all of its key values. Note that in order to preserve the transformation properly when a rotation is applied, the animated entity may be placed into a new group in the Animation

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Animating color

Some animated entities can have color tracks to animate a color parameter. For example, you may want to change a scene’s mood by animating a light’s color, or animate a subtle color change like metal becoming red-hot, or illustrate differences in the brick color of a building.

There are two ways of animating a color. Since a color is actually made from three values, many options could apply for how two colors are transformed from one to another. form•Z offers a simple method and one that allows more user control.

The simple way is to add a single color track, and then specify a set of colors. form•Z will then automatically interpolate the three color components of each color from one color to the next. This is the easiest way and recommended for most purposes.

The way for more user control is to add three separate color tracks, one for each color component. The burden is then upon the user how the three components combine to make new colors. This way is only necessary if you wish to animate one color component differently than another component.

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Animating materials

As with objects, lights, and views, the parameters of a material can be animated. Recall that a material may have a number of different representations. For example, when form•Z RenderZone is installed, there are two representations: the Simple and the RenderZone representation, each of which appears as a separate tab in the Material Parameters palette. Each of these tabs contains its own group of parameters. In addition to these default representations, plugins may install more representations, which are also grouped in separate tabs.

The default form•Z representations allow the user to animate most of their parameters, which are accessible at different levels. For example, the parameters of the Simple representation are shown directly in the tab for this representation. Other representations may require to open additional dialogs where different parameters may be accessed. The animatable parameters have the standard animation bullet menu displayed next to them, which works as discussed in a previous section. The parameters of the RenderZone representation are further grouped by shader type and are usually accessible through shader options dialogs that need to be opened. Exceptions are shaders that have only a single color parameter, such as the Plain color shader. In these cases, the color box is shown directly in the RenderZone tab with a bullet menu next to it.

As with objects, lights, and views, you make a material animated by dragging its icon from the Materials palette into the Animation Editor palette. When this is done, all animatable parameters of the material are assigned a track. Unlike objects, lights, and views, a material does not have a graphic representation in the main project window. Thus the Keyframe tool can not be applied to materials.

A material is an attribute of objects and faces. This means that, if a material is animated, all the objects and faces that use that material will automatically show the animated effect.

The animatable parameters of a material can be further classified into three types and are discussed under these categories in the remainder of this section: color parameters, the Frame Time parameter of image map based shaders, and numeric parameters.

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Animating material colors

Within the context of materials, by animating color parameters one can, for example, make an object transition smoothly from one color to another. Such an effect can be achieved by the following steps:

• Assign a material with the Plain Color shader to an object.

• With the time line set to 0 in the Animation Time Line palette, double click on the material’s icon in the palette to invoke the Material Parameters palette. Click on the red bullet next to the Plain Color box and, from the menu that pops out, select Add Track (shown below).

• Move the time forward in the Animation Time Line palette.

• Enter the Material Parameters palette for the same material again. Click on the Plain Color box and choose a different color from the color picker dialog. Exit from the Material Parameters palette.

You can preview the animation (the object changing color) by setting time to 0 in the Animation Time Line palette and clicking on the Play button. You can also create an animation using the RenderZone display mode and see the object change color.

Animating the color parameter of the Plain Color shader of a material.

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Animating the frame time parameter of map based shaders

The RenderZone representation of a material has three shaders, which may be based on texture maps. These are the Color Map, the Transparency Map, and the Bump Map shaders. In the options dialogs for each of these shaders is a parameter labeled Frame Time, as shown for the Color Map Options dialog in the example below. If the file selected for the map is a movie file, such as a QuickTime movie, the image used for the rendering is one of the frames of the movie. The Frame Time field allows the user to choose which frame of the movie to display. The time value is entered in Hours:Minutes:Seconds format in the text edit field.

One application of a movie based image map would be to animate a television screen (see animation tutorials section). The steps required are identical to the steps of animating a color. To play the movie in its original speed, the time value entered for a key frame should be the same as the time value of the key frame in the time line.

The Color Map Options dialog with a movie file loaded.

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parameter from 0 to 100%.

A light object blinks:Choose a bright Plain color and the Matte reflection shader. Animate the Matte shader’s Glow parameter from 0% to 100% and back, in a cyclical fashion.

A relief emerges out of a surface:Choose a texture map with a relief as a Bump Map shader. Animate the

Amplitude parameter from 0% to 100%.

A piece of metal rusts away:Choose the Eroded transparency shader. Animate the Coverage

Animating the Transparency parameter from 0 to 100%.

Animating the Amplitude parameter from 0 to 100%.

Animating the Coverage parameter from 0 to 100%.

Animating numeric shader parameters

The remaining shader parameters represent different kinds of numerical values and can be animated, as described earlier. Given that there is a great number of ways in which shader parameters can be combined, one can create a huge number of animated effects. Some examples follow:

An object becomes slowly invisible:Use the Simple Transparency shader and animate its Transparency

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accurately. There are two ways to update the preview icon.

• First, the Material Parameters palette may be invoked by double clicking on the preview icon. This will render the preview in the dialog and, after it is closed, will show the new preview in the palette.

• Second, clicking inside the yellow triangle in the palette will also render a new preview. Note, that this may be instantaneous or

may take a few seconds, depending on the complexity of the material.

Limitations

Certain parameters of a material can currently not be animated. They are:

• The parameters of the reflection map shaders for each of the standard reflection parameters (ambient, diffuse, specular, reflectivity, transmission and glow).

• The Noise parameters of shaders that use random noise.

• The Area Sampling parameter of shaders that offer area sampling.

• The environment related parameters of the Environment reflection shader.

The Materials palette.

parameter from 0% to 100%.

Preview icons of animated materials

If a material has any animated parameters and the time line is changed, the preview icon in the Materials palette shows a small yellow triangle. It indicates that the preview icon no longer represents the material parameters

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Animated color options

The options of a color track can be accessed through the Animated Color Options dialog (Example to the left), which can be invoked by double clicking a color track in the Animation Editor palette or by right clicking it and selecting Controller Options... from the context menu.

Color Type: There are two methods for defining color and one of them can be selected from this group of options, as follows:

RGB: When selecting this option, Red, Green, and Blue will be used to define the color.

HSL: With this option on, Hue, Saturation, and Lightness will be used to define the color.

Tracks: In this section you determine whether a color will be animated with a single or three tracks.

Use 3 Separate Children Tracks: When this option is on, form•Z will use 3 children tracks to define this color. This means that you will have to combine 3 Bezier controllers to make the color. If the Color Type is RGB, separate Red, Green, and Blue tracks will define the color, in a range of 0 to 100%. If the Color Type is HSL, separate Hue, Saturation, and Lightness tracks will define the color, again in a range of 0 to 100%. Use the Animation Editor palette to animate the 3 color component tracks of colors.

Use Single Track: When this option is on, form•Z will use a list of colors and interpolate between them. The colors list defines all the colors of the animated color. Use the Add button to add another color to the list. Use the Delete button to remove a color from the list. To change a color, double click on it, in the list. You may also drag colors in the list to change their order. When you use this method you have a single Bezier controller that controls how one color transitions to another. Use the Animation Editor palette to edit the Bezier curve and set how one color transitions to another.

The Animated Color Options dialog.

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When Use Single Track is on, form•Z will take into consideration the Color Type when transitions between the colors in the list. If RGB is selected, one color transitions to the next as if the 3 RGB values were being interpolated. This means that, if a pure red color were being changed to a pure green, the color between them would be a muddy color. If the Color Type were HSL, red would transition through orange, yellow and then become green.

Animated color example

To animate a light changing color from blue to green, add the light’s Color track to the Animation Editor palette by clicking the red dot next to it and selecting Add Track from the popup menu. Open the Animation Editor palette and fit the visible tracks. In the track list, highlight the Color track. Double click it to open its options. In the Colors list, double click the first color and change it to blue. Then add a green color. Select OK. Next, locate the only keyframe of the color track. Change its time to 0 if it is not already at 0. The value of the keyframe should be aligned with the blue color shown in the value axis. We want to animate to the green color shown in the value axis. In Insert mode, insert a new keyframe at frame 100 at approximately the vertical position of the green color. Now the color will change from blue to green between frame 0 and 100.

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Generating and saving animations

After all the parameters for an animation have been set, the frames that compose the animation need to be rendered and stored in a form•Z anima-tion file. The animation file can then be played back on the screen.

The Animation Generation dialog with Animation File selected from the Store

Frames In menu.

Generating animations

To render the frames of an anima-tion, the Generate Animation... command is selected from the Display menu. It invokes the Animation Generation dialog, shown to the right, which con-tains the parameters required for the rendering. After the desired options have been selected, the animation frames are rendered in sequence and added to the animation file. As each frame is rendered, the modeling window refreshes to show the image of the frame. The progress bar shows the number of frames that have been rendered and the Animation Time Line palette shows the time and frame number, as frames are rendered.

Display Type: This pop up menu determines which type of render-ing is used for the animation. The options currently set in the dialog for the selected rendering type are used for each frame of the animation. Pressing Options... next to the menu invokes the Options dialog for the currently selected rendering type.

Two of the rendering types available are Shaded Work and Shaded Full, which usually are performed by video hardware. Consequently, form•Z’s ability to capture the image from the hardware depends on the card and its driver. For best results, make sure that none of the form•Z palettes or any other window obscures the form•Z window being rendered.

Despite advanced antialiasing techniques that may be available, an anima-tion based on this display type may show artifacts which appear as flickers. These are usually most noticeable where a pattern on the screen is of high

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contrast and small scale or along edges which are almost, but not exactly, vertical or horizontal. For example, when moving along a sequence of closely placed columns, the vertical edges of the columns may flicker. The following three options are designed to reduce or eliminate these artifacts. They can be used individually, or in combination with each other. Note, that these options are available for all rendering types.

Super Sampling: When this option is selected, the entire frame is super sampled. That is, for each pixel on the screen additional samples are ren-dered, which leads to improved antialiasing. How many samples per pixel are taken depends on the option selected from the menu. Low renders a grid of 2x2, Medium 3x3 and High 4x4 samples. Note that super sampling will lead to increased rendering times for pixel based rendering modes. For example, if High is used, 16 additional samples are rendered per pixel. This may increase the rendering time up to 16 times.

Motion Blur: When this option is selected, a number of subframes are generated and averaged with the original frame. This captures motions that occur faster than the frame rate and blurs them to achieve a more natural look. The more subframes one specifies, the higher quality the blurring looks, but the longer the animation takes to generate.

Blur Filter: Areas of high contrast in animation tend to flicker when played back. To avoid the flicker, they can be further softened by blurring each frame. Although each individual image will lose some of its crispness, the blur is much less noticeable in an animation. How much blur is necessary to reduce flickering depends greatly on the animation. In some instances, blur may not be neces-sary at all, whereas other scenes may need a high degree of blur. In general, if an animation contains patterns with high contrast and small scale, blur will be necessary to remove flickering artifacts. How much blur is applied depends on the option selected from the menu. Note that unlike Super Sampling and Motion Blur, Blur Filter does not significantly increase rendering time.

Frames To Render: The options in this group specify which frames of the animation will be rendered at this time. All the frames will have to be rendered for the final animation, however, they do not need to be rendered all at once. Rendering only some strategically chosen frames allows us to preview the animation and make adjustments as necessary, before spend-ing the time to render all the frames.

All Frames: When this option is on (default), all of the frames in the ani-mation are rendered.

Frame Range: When this option is selected, a range of frames can be specified to be rendered. This is done with the following parameters.

Start, End: The values entered in these numeric fields specify the beginning and end frames to be rendered.

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Current: Clicking on this button sets Start and End to the current frame, as marked in the Animation Time Line palette.

Every n Frames: The value in this field specifies an interval for skipping frames between the Start and End. Frame List: When this option is selected, a variable list of frames can be specified. This list can include single frame numbers separated by commas or a range of frames indicated by a dash and also separated by commas. For example “10, 31, 35-45” would render frames 10, 31, and 35 through 45.

Generate On Local Machine: When this item is selected, the animation is generated in a designated file on the local machine.

Store Frames In: This pop up menu contains two items, which allows the user to determine whether all rendered frames are stored in an animation file or whether each frame is saved to a separate image. Depending on which item is selected, a different set of options are displayed below it in the dialog.

Animation File : When this item is selected, all the frames are stored in an animation file designed for movie playback. The area below the menu contains information about the name and location of the current animation file as well as options about how to save the animation file. By default, the animation file takes the name of the project with a “.fan” extension at its end. The default location is in the same directory as the project file.

Format: On Macintosh, this menu contains: form•Z Animation and QuickTime™ Movie. On Windows, this menu contains: form•Z Animation, AVI, and QuickTime™ Movie. Each generates the respective animation format.

Compression: This menu determines what type of compression, if any, is applied to the animation file.

Off: When selected, no compression is applied.

Deflate: This item is only enabled when the Format is set to form•Z Animation. When selected, the Deflate algorithm is used to produce smaller .fan files.

QuickTime: This item is only enabled when QuickTime is se-lected from the Format menu. When selected, the QuickTime compression engine is used to compress the movie file. The Options... button to the right is used to access the QuickTime Compression options.

AVI: This item is only available on Windows and is only enabled when AVI is selected from the Format menu. When selected, the AVI com-pression engine is used to compress the AVI file. The Options... button to

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the right enables access to the AVI Compression options.

Keep Existing Frames: When this option is selected, any frames that are already rendered and are in the animation file from a previous genera-tion are kept in the file. Any new frames that are generated replace any previous renderings of the same frame that may exist in the file. When off, which is the default, all rendered frames are cleared at the start of genera-tion. If some critical parameter of the animation is changed (such as the dimensions), then the older frames in the file are automatically cleared.

Do Not Re-Render: When this option is on, frames that exist in a file are not re-rendered even if they are specified in the Frames To Render section. This keeps existing frames from being overwritten in the file. This option, off by default, is most useful when some frames of an animation have been rendered for previewing and you want to render the remaining frames. Use this option along with the All Frames option to complete the animation.

New File...: Clicking on this button invokes a standard Save dialog where a location for the file, other than the default, can be selected and a new file name can be entered. After exiting the Save dialog, the name and location of the animation file are displayed.

The Frame Info dialog.

Choose File...: This button is an alternative to New File... and allows you to open an existing file with a previously saved animation for saving the new or revised animation.

Frame Info: This button invokes the Frame Info dialog, shown to the right. It displays the status of the frames already rendered and of those that remain.

Playback When Finished: When this option is on, the animation is automatically played back, after the generation is complete. When this option is off, the animation can be played back as discussed in the next section.

If a long animation is created with a large image resolution, it is quite possible that the file size of the animation file will exceed a limit of 2 gigabytes. In such a case, the Format chosen should be form•Z Animation, which is able to split the entire animation over several files. If, during the animation generation, the initial animation file is about to reach the 2 gigabyte limit, a new, “overflow” animation file is created with the same name and “-2” appended. This new file will then be used. If it also reaches this limit, a third file will be created,

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etc. Each such overflow file is independent from the others and can be played back by itself. Care should be taken when re-rendering new frames to an existing set of animation files. If the Keep Existing Frames option is off, all overflow files derived from the original animation file are deleted together with the original file. If the Keep Existing Frames option is on, new frames are always appended to the last of the overflow files. If the rendered frames are not in sequence with the frames in the last overflow file, the animation won’t play back the frames in the proper order. For example, consider three animation files, one original and two overflow files, with the first two containing 10,000 and the third containing 5,000 frames. If the user would choose to re-render frames 1-1000 with the Keep Existing Frames on, these frames would not be overwritten in the first animation file, but would be appended to the last animation file. One scenario where the Keep Existing Frames option can be used with overflow files, is when an animation is cancelled by the user and needs to be resumed at the cancelled point. The animation can be continued by using the Frame Range option and setting the Start to the frame, where the animation was previously cancelled. To find the last rendered frame, the last overflow animation file should be played with the View File... command, where the frame coun-ter can be seen in the playback window. Keep in mind, that the overflow feature is designed to allow for the final production of a large animation without exceeding the 2 gigabyte file size limit. It is not meant to support flexible frame re-rendering.

Separate Image Files: When this item is selected from the Store Frames In menu of the Animation Generation dialog, each frame of the animation is saved as a separate image file. The options below the menu change and contain information about the name, format, and location of the image files.

Format: This menu contains all installed image formats, that support pixel images. The Options... button next to the menu invokes the respective Options dialog associated with the selected format.

Base Name: The name entered in this field determines the file name of the image files. A 5 digit counter is appended to the base name, which identifies which frame is saved in the file. For example, if Base Name is set to “my_animation”, the 100th frame saved to a TIFF file would create a file called “my_animation-00100.tif”. Note, that any files that already exist with the same name, potentially from a previous animation generation, are overwritten

Part of the Animation Generation dia-log with Separate Image Files selected

from the Store Frames In menu.

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without warning.

Location: This field shows the directory where the image files will be saved.

Choose Location...: Clicking on this button invokes the standard Choose A Folder dialog, where the location for the image files can be changed.

The Animation Network Render dialog.

Generate On Network: When this option is selected, the animation is generated on the network. When the Generate Animation... but-ton is clicked with this option on, the Animation Network Render dialog (shown below) is invoked. Its options are as follows:

Job Name: The name of the rendering job is entered in this field. This identifies the job in the job queue.

Server: This pop-up menu identi-fies the rendering server that the job will be sent to. The Settings… button invokes the Network Set-tings dialog, discussed in the Network Rendering section of the form•Z User's Manual.

Priority: This slider determines the priority assigned to the job. If the priority selected exceeds the user’s priority, the job priority will be capped to the user priority.

Keep Project On Server: When this option is selected, rendering content files (form•Z project files, textures, etc.) are kept on the server for future renderings. This option is only available when the Registered User option is selected for the current server, as set in the Server Settings dialog.

Project: This pop-up menu identifies the name of the project to use for the rendering job. The project name is used to identify all of the rendering content files for the project. This name will be used in the directory name on the server machine where the files are stored.

Add...: This button can be used to add a new project name to the list.

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The Add Project dialog is invoked for entering the name of the project.

Remove...: Clicking on this button removes the current project from the project list. This will also delete any associated jobs which use this project. This will remove the project and its jobs from the server as well.

File Retrieval: This group of options is used to determine how the completed renderings and animations are retrieved from the server.

Manual: When this option is selected, completed renderings and animations are retrieved manually by the user. Manual retrieval is done by selecting the Retrieve... button in the Network Status dialog.

Automatic: When this option is selected, completed renderings and animations are automatically retrieved when they are completed. Note that automatic retrieval only happens while the form•Z application is running.

Display Image After Retrieval: When this option is selected, the completed rendering will automatically be displayed, once retrieved from the Server.

Leave File On The Server: When this option is selected the com-pleted rendering or animation is left on the server after retrieval. This option allows for future manual re-retrieval.

Store Frames In: This pop-up menu determines how the rendered animation will be stored.

Animation File: When this item is selected, the animation is saved as a FAN file.

Separate Image Files: When this item is selected, each frame of the animation is saved as a separate image file. The format of the image files is set by the next menu, which appears when this item is selected.

Exporting animations

An exportable movie format can be produced from the form•Z animation format (.fan) by executing the Export Animation... command in the File menu. This converts the form•Z animation into a common animation file or into a set of independent image files. The supported animation files are QuickTime Movie (available in Macintosh and Windows) or AVI file (Windows only). To be able to export into a QT Movie format, QuickTime v. 6.0 or later must be used on both the Macintosh and Windows. It is recommended that you use the latest version of QuickTime available. Please see www.QuickTime.com for the latest QuickTime versions. The image formats are all of the image based formats that could be used to save a static image

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(TIFF, Targa, etc.).

When selecting the Export Animation... command, a standard File Open dialog is presented from where the form•Z animation file (.fan) to be exported is selected. Once the file is identified, double click on it or click on the Open button. The standard File Save dialog appears for the naming of the exported file, for identifying the location where it will be stored, and for selecting the export file format. Once the desired options have been set, press Save to export the movie. A progress bar shows the progress as each frame of the animation is converted and exported.

Available expor t options are QuickTime or AVI, plus the image for-mats. When exporting to QuickTime, clicking on the Save button invokes the standard QuickTime compres-sion dialog, shown to the right. Given that QuickTime supports a variety of compression types that can be expanded with third party plug-ins, the appearance of this dialog may vary from computer to computer.

When exporting an animation to an image format, the frames of the ani-mation are saved to individual files. The name of each file contains the frame number following the name entered in the Save dialog. The Animation Frame Export Options dialog (right) is automatically invoked after the Save dialog when exporting to an image file. This dialog allows for the selection of the frames from the animation which should be exported. The options in this dialog function as the same options in the Animation Generation dialog (see earlier in this section); except that they control which frames should be exported rather than rendered. If a frame is specified that does not exist in the animation file (.fan), it is skipped.

The standard QuickTime compres-sion dialog.

The Animation Frame Export Op-tions dialog.

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Tutorials

This section contains seven tutorials that attempt to cover the different variations of animation with relatively simple examples. The best way to read the material in this chapter is in the order it is provided. That is, the theoretical sections should be read first, followed by the tutorials in this sec-tion, in the order presented. While they all offer step-by-step instructions, the early tutorials are more detailed than the latter ones. That is, some theoretical explanations are given in the first couple tutorials, but are not repeated in subsequent tutorials.

While in all tutorials we expect the reader to be in a position to generate the required models, even though we do not give any modeling instructions, we also provide files with the initial models required by the tutorials. The Tutorials folder can be found on your program DVD or can be downloaded from our website http://www.formz.com/support/downloads/tutorials.html.They are organized in folders carrying the same indices and names similar to the titles of the tutorial subsections. For each tutorial there is a file carry-ing the label "...Base," another one carrying the label "...Complete," a third that is a .fan file (form•Z animation file), and a fourth that is a QuickTime movie.

The Base file contains the initial model required to start the tutorial. The Complete file is for comparison, after you complete the tutorial, especially if you have a difficulty with some portion of the tutorial. The .fan file contains a rendered animation and is intended to show you roughly how yours will look after completion. A QuickTime movie is easily generated from the .fan file and can be played independently of form•Z.

The form•Z project files are all set up with an image size of 640 x 480 pix-els. The .fan and QuickTime files were created at 320 x 240 to meet CD size constraints. The image size can be changed in the Image Options dialog, accessed from the Image Options item at the bottom of the Display menu.

Even though we provide you the "answers" and basically expect your animations to look more or less like ours, we would also like to encourage experimentation. Once you grasp the basics, you should feel free to ex-periment and explore beyond what we suggest. Actually, the more capable you are to deviate from what we give you the more knowledgeable you will have become of the form•Z animation techniques.

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Swinging door tutorialThis tutorial will cover the creation and animation of a door swinging open. This is the first of a sequence of animation tutorials that are covered in this section and covers more details than the subsequent tutorials do. That is, some explanations about what is the meaning of some of the operations you will be asked to apply are included as well as some term definitions, rather than simply giving you instruction about what to do. This way this is more of an introductory session than the following tutorials are.

Simple animations, like the opening door that you will be doing shortly, can be accomplished easily using the Keyframe tool, while additional methods are also available and will be covered by subsequent tutorials. In all cases, you first need to set up the model you will be animating. For this tutorial, either open the sample file "Swing-ing Door Base", found on your program DVD, or build a simple door yourself. If you do, change its name to "door_geometry" so that the illustrations we show agree with those you will be observing on your screen. The door in our file is as shown to the right. If you build it yourself, it will probably be a lot simpler. In spite of this, all the animation values and settings you will be generating for this tutorial will look exactly the same regardless of which door you use. As a matter of fact, you can also do what is standard practice among anima-tion professionals: set your animation with the simplest door possible and then transfer these settings to a more elaborate design of a door.

You will first prepare your door to rotate as you want it for this tutorial.

Select the Edit Axes tool from the Mod-eling workspace and click on the door.

Notice that the door highlights in orange and a transform widget appears at the center of the door where the axis currently is placed.

• Turn on Snap to Point ( ). • Click at the center of the transform widget and move it down to the front, left corner of the door.

The door with the axis at its base.

The door with the axis moved to the bottom left corner.

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Your door is now ready to start the animation process. Change workspac-es to Rendering/Animation.

With the Keyframe tool active, click on the door.

A blue line is displayed at the left end of the Animation Time Line palette. This represents a key and indicates that the door is now animated.

the Animation Options palette and in the Timing tab, make sure the Time Display Format is set to Seconds.

• In the Animation Time Line palette, move the current time forward to 2 seconds.

• Make sure the Auto Keyframe ( ) button is on.

With the Transform tool rotate the door 90° clockwise about the Z (vertical) axis as shown in the example.

A clarification about the sign of the rotation is in order. form•Z gives you the option to spec-ify whether clockwise or counter-clockwise is

considered a positive angle. This is done in the Project Settings: Working Units dialog (Angle Options tab) invoked from the File menu. By default, positive is counter-clockwise. Thus, assuming you did not change the de-fault setting, the rotation you just did was negative 90 degrees.

Because Auto Keyframe is on, any changes made to an animated object are saved at the current time. In this case, another keyframe is automatically made to save the rotated new position of the door.

To test this, grab the current time marker in the Animation Time Line pal-ette and drag it left and right. Notice the door swings open as the animation

Rotating the door.

The Animation Score section of the Animation Editor palette.

• From the Palettes menu, open the Animation Editor palette. Notice the "door_geometry" object is listed. Click on the arrow before the name to expose its contents. Observe that several attributes are listed. Recall that these attributes are called tracks and are generated by default when applying the Keyframe tool.

• From the Palettes menu, open

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moves forward in time.

• From the Palettes menu, open the Animation Options palette. In the Preview tab under Entity Preview, make sure Show Keyframes is off. You may now close the Animation Options palette.

• In the Animation Time Line palette, hit the Play button and observe the door open and then stop. It stops as soon as it reaches 2 seconds and stays open as time continues to move all the way to 10 seconds, at the right end of the time line. Then it cycles back to 0 seconds and starts again. At any time, hit the Stop button.

Note that, had you not turned off Show Keyframes, the image of the door would be shown dimmed at the positions of the two keyframes. Now that this option is off, the keyframes are not shown.

Animation Editor palette

Next, you will adjust the animation curve (the graphic representation of the track for Rotation Z) to make the motion of the door more realistic. Cur-rently, the motion looks mechanical as it opens at a very constant speed. With a little adjustment you will make the door swing more naturally. You can also make the door appear to slam open or perhaps to appear as though it is blowing in the wind. You will do all these adjustments working in the Animation Editor palette.

• From the Palettes menu open the Animation Editor palette. The door object name and the tracks it contains should be listed in the upper left area of the palette and a graph should be displayed to the right. If the tracks are not listed, click on the triangle in front of the door name to expose them.

• Above the graph, there is a row of buttons. Click on the Fit Visible

button ( ), which is the third from the left. The graph is adjusted to occu-

py the graphic area, as shown below. The graph consists of a single straight

The Animation Editor palette.

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The Animation Editor palette graph, after moving the lead in of the sec-

ond keyframe down.

line corresponding to the Rotation Z track. It is oriented diagonally, which represents the constant speed with which the door opens, as you observed earlier.

The remainder of the tracks (Position X, Y, and Z, Rotation X and Y) are currently graphed in the window as single dots on the left vertical axis, which means they only exist at time 0 and they have not been animated. You may actually make their graphs disappear by toggling off the eye sym-bols ( ) displayed next to them, in the second column of the list.

• Click on the Rotation Z track to highlight it.

The graph of Rotation Z in the Animation Editor palette shows all the key-frames. How the data is interpolated between keyframes is controlled by the leads attached to each keyframe. The leads are drawn as a line with a circle at their end and are coming out of both sides of a keyframe. The lead on the left of a keyframe is called the lead in while the lead on the right is called the lead out.

For the Rotation Z of the door, experiment with the positions of the leads to see how they affect the motion of the door. For example, grab the lead in of the last keyframe and drag it up so that it is some distance vertically above the keyframe. This will make the animation curve turn almost vertical as it is drawn into that sec-ond keyframe. Also drag the lead of the first keyframe to the 0 line. To confirm the effects of these chang-es, minimize the Animation Editor palette and play the animation from the Animation Time Line palette.Now that you have played the ani-mation, you must have noticed that, while a diagonal orientation of the

graph represents even speeds, portions with more or less vertical orientations represent fast speeds and portions with horizontal orientations represent slow speeds. When reading the graph of a track, to figure out the behavior it repre-sents, compare the distance traveled on the vertical axis relative to time, the distance traveled on the horizontal time. The longer the vertical distance, the higher the speed.

Next, you will make the lead into the second keyframe flat. This will gently ease the motion into that position.

• Open the Animation Editor palette and highlight the second key-frame of Rotation Z.

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Adding keyframes

Next, you will make the door appear to be abruptly pushed open, slam into the wall, and rebound slightly. You will do this, by adjusting the value in the existing keyframe and by adding one more keyframe.

First, adjust the existing keyframe to make the door slam into the wall. Logi-cally, the door would be at roughly 180 degrees when it strikes the wall. You will make the adjustment to the rotation angle directly in the Animation Editor palette.

• Open the Animation Editor palette and click on the Zoom out (

) button (second from left) as many times as necessary until the -180°

mark is displayed on the vertical axis. • Now drag the second keyframe vertically to the -180° line. The time remains the same, which is 2 seconds. This will cause the door to open by 180° and slam against the wall.

You will next adjust the lead out of the first keyframe to imitate a sudden opening of the door. This can be done by making the lead out for the first keyframe linear.

• Click on the first keyframe. Below the graph in the Key section of the Animation Editor palette, locate the Lead Out group and choose the Linear option ( ).

Notice that the lead has disappeared from the first keyframe. The lead out for the first keyframe is basically pointing at the end of the lead in for the second keyframe. Drag around the lead in for the second keyframe to ob-serve the behavior of the graph.

To adjust the lead in for the second keyframe to be Linear, use the same technique as above.

• Highlight the second keyframe. Below the graph in the Key section of

• Click the Flat ( ) button.

Note that the lead in is positioned di-rectly left of the keyframe. The lead handle can be stretched further left to make the lead in even flatter.

• In the Animation Time Line palette, click Play. The door starts to swing out and gently comes to a stop. Flat leads will give objects a smooth and fluid motion.

The Animation Editor palette graph, after flattening the second keyframe.

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The Animation Editor palette after adding the third keyframe at .7 sec-

onds.

the Animation Editor palette, locate the Lead In group and choose the Linear option ( ). Click on the Fit

Visible ( ) button and observe the perfectly straight line connecting the two keyframes.

Play the animation. With the sec-ond keyframe set to a value of -180° and a time of 2 seconds, the door appears to open rather slowly. Thus you will make some more adjust-ments, next.

• In the Animation Editor pal-ette click on the second keyframe. • Change the Time field to 0.5 and observe how it changes the graph. • Play the animation. It appears as if the door swings open and then sticks to the wall.

Next, give the door a little rebound, so that it bounces off the wall. This

The Animation Editor palette after the second keyframe is set to .5

seconds.

The Animation Editor palette graph, after making both keyframes linear.

requires the addition of one more keyframe.

• In the Animation Editor palette, activate the Insert ( ) button and click on the space after the second keyframe, to add one more keyframe. • Highlight the second keyframe and click the Linear option ( ) in the Lead Out section. This makes a linear lead out from the second key frame. • Set the Value of the third keyframe to -165° and the Time to 0.7 sec-onds. • Adjust the lead in of the third keyframe to be flat. To do this select the third keyframe and then click on the Flat button ( ).

The graph should now appear as the one shown to the right.

• Play the animation and observe the motion of the door.

The sharp point formed by the line going into and out of the second keyframe is what gives the motion

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that abrupt reversal in direction. Since the angle of the outgoing line from the second key is a little less steep, the speed of the door on the rebound will be a little slower. The speed decreases from there until coming to a soft stop. The gentle end is due to a flat lead in on the last keyframe.

A door swinging in the breeze

You will next make the door appear to swing in the breeze. While there are many ways this can be done, a simple method will be used in this tutorial.

• Select the first keyframe in the Animation Editor palette and change the Value field to -15. • Make the lead out of the first keyframe curved. You do this by high-lighting the first keyframe and selecting Curved ( ) from the Lead Out section under the graph. This causes a lead to appear. • Click on the Flat button ( ) above the graph to make the lead flat, then drag that lead further right to make its curve still flatter as it exits the keyframe. • Change the last keyframe to a Time of 4 seconds and a Value of -15. It should have a curving lead in. Make it Flat. It should be roughly a mirror image of the first keyframe. • Set the second keyframe to a Value of -60 at a Time of 2 seconds. Also make this keyframe have a curved lead in and lead out that are Flat.

The graph should now look like the graph to the right. If not exactly, make additional adjustments by manually moving some of the leads as neces-sary to roughly match the graph in the example.

• Click Play in the Animation Time Line palette to review the anima-tion.

The door should gently swing partially open and gently swing back.

To make this door constantly flap in the breeze, the animation can be

The Animation Editor palette graph of a track that makes the door swing.

made to repeat.

• In the Animation Editor pal-ette, right click the Rotate Z track and select Track Options... Click the button labeled After and, from the Type pop up menu, select Re-peat Normal.

• Click on the Fit Animation

( ) button and observe how the

graph repeats itself and covers the

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complete span of 10 seconds.

• Play the animation.

When you played the animation, you noticed that the door swings continu-ously. After 10 seconds it returns to time 0 and starts all over again, thus go-ing continuously until you hit Stop.

You must have observed that when it cycles back to 0 from 10 seconds, the motion is not smooth. It jumps from the open to the closed posi-tion rather than closing smoothly, as it does the other times. This is be-cause the 4 seconds do not divide exactly the 10 seconds. To correct this we need to either extend the 10 seconds (say to 12) or to reduce the 4 seconds (say to 2.5). In this tuto-rial we shall do the latter.

The Animation Editor palette graph after the selection of Repeat Normal

and Fit Animation.

• In the Animation Editor palette, highlight the second keyframe and in the Time field enter 1.25. • Next, highlight the third keyframe and in the Time field enter 2.5.

Note that we could also click and drag these keyframes to the sug-gested time positions, but it is more accurate to just type the desired val-ues.

• Click on the Fit Visible ( )

button. Your graph should be as

shown in the example.

• Click on the Fit Animation (

) button. Note how the position at time 0 matches exactly the position at time 10, which will allow the door swing to transition smoothly.

• Play the animation.

The Animation Editor palette graph of a track that makes the door swing.

The Animation Editor palette graph after the selection of Repeat Normal

and Fit Animation.

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Bouncing ball tutorialIn this tutorial, you will create a bouncing ball. You will first generate a model of a sphere and then you will animate it. • In the Modeling workspace, select the Sphere tool ( ). In the tool options select Preset ( ) and change the Radius X to 6". With grid snap on ( ), click once on the center of origin of the reference plane (there are several ways to create the sphere, feel free to use whatever technique you like). • Double click the middle mouse button (3 button mouse), click the Fit All button ( ) or zoom to whatever scale that allows you to see the sphere well. • To the right of the Grid Snap icon, set grid snapping to 6". Click on the sphere with the Move tool ( ), toggle the perpendicular switch by tapping the Command key (Macintosh) or Control key (Windows) and move the sphere vertically 6" along the Z axis (so that the bottom of the sphere is on the XY plane).

You will next move the local origin and axes of the sphere to its lower end, which currently sits on the origin of the refer-fence plane.

With the Edit Axes tool click on the sphere.

This displays the local axes and origin of the sphere.

• Click on the axis origin and drag it to the bottom of the sphere along the Z axis, as shown to the right.

You will next add some basic animation to

The sphere with its local axis moved to its lower end.

the sphere, change workspaces to Rendering/Animation.

Activate the Keyframe tool and click on the sphere.

While nothing very visible happens, the sphere has been animated and a keyframe symbol appears in the Animation Time Line palette. Also, animation information has been entered in some of the other animation supporting palettes, as you will see soon.

• From the Palettes menu, open the Animation Editor palette. • Click on the little triangle in front of the object name to expose its content. It contains a number of default tracks, which are not needed for this example, therefore they will be deleted. • To delete a track, right click it and select Delete from the context

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menu. Delete all the tracks except for Position Z. • Next, in the Palettes menu, open the Animation Options... palette. In the Timing tab change the Time Display Format to Frames. This changes how time will be displayed. Close the palette to return to the main window. Note that some users prefer to work in time units of seconds, oth-ers prefer to work using frames. • In the Animation Time Line palette, in the Frame field, located at the lower portion, enter 28. Make sure the Auto Keyframe button ( ) is on. • Click on the sphere with the Move tool ( ), toggle the perpen-dicular switch (if not still set) by tapping the Command key (Macintosh) or Control key (Windows) and move the sphere vertically 4' along the Z axis. • From the Palettes menu, open the Animation Editor palette and click on the Fit Visible ( ) button.

Notice that there is a blue line in the graph that represents the Z position of the sphere. There are also two dots, one at each end of the blue line. These dots represent the keyframes of this track. The line between the two dots shows how the track is interpolated between the keyframes. With only two keyframes, the line is straight.

On the line, between the blue dots, there are two white dots. These are at the ends of the leads, which are controls of the keyframes. You will soon see that these white dots do not have to be on the blue line and that by moving them in different positions you can control the type and intensity of the motion at the respective keyframe.

You can add more keyframes to tracks by activating the Insert tool (

The Animation Editor palette.

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) and clicking in the graph where we want the new keyframe to be added. You will do such an insertion next.

• Highlight Position Z in the list on the left side of the palette. Click on the Zoom Out tool as many times as necessary until you can see the 58 frame mark.

Activate the Insert tool ( ) and click in the graph approximately at the point that has a 0 value (vertical axis) and a 56 frame (horizontal axis). You are assisted by a "hint" display that shows you the position you are at before you actually click to make the insertion. As soon as you click, you notice that a new keyframe or dot is added where you clicked and the blue line is now connecting this keyframe to the first two. Click on the Fit Visible ( ) button again.

If you have difficulty inserting a keyframe at exactly the desired position, you can still adjust the position after the insertion has been made. While the keyframe is highlighted, its Time and Value are displayed in two nu-meric fields at the lower middle portion of the palette. If they do not show 56 and 0, you can type these numbers in.

You will next play the animation up to this point.

• Minimize the Animation Editor palette.

The Animation Editor palette.

• In the Animation Time Line palette, with the mouse, move the cur-rent time symbol to 0.

• Click Play. As the time symbol in the palette moves from the 0 to the 56 frame, the sphere bounces up and down once and stops, while the

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time symbol continues to move to the right. When it reaches the end of the palette it goes back to the beginning and the sphere bounces once again.

If we want the sphere to bounce continuously, we can do it through the Animation Editor palette.

• Open the Animation Editor palette, right click the Position Z track and select Track Options.... Click the After button and from the pop up menu under it, select Repeat Normal.

Click on the Fit Animation ( )button. The palette should now ap-pear as it does below.

In the graph area of the palette, you will see that the original line has been repeated as many times as necessary to fill the time span available for this animation. The repetitions are shown in a light blue line.

Minimize the Animation Editor palette and from the Animation Time Line palette, play the animation again. Observe how it plays continuously.

The Animation Editor palette.

As you were playing the animation and the ball was bouncing up and down continuously, you must have noticed that its motion appeared unnatural and mechanical. In order to make the sphere bounce more naturally, we need to adjust the way in which the position of the sphere is interpolated between the keyframes.

• Reopen the Animation Editor palette.

Click on the Fit Visible ( ) button again.

Look at the middle keyframe. Notice the line with the white circles at its ends, coming out both sides of the keyframe. These are the leads that

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Changing the leads of the first and last keyframes, in the Animation Edi-

tor palette.

Changing the leads of the middle keyframe.

control how the curve enters and leaves the keyframe. You will next manipulate the leads to change how the sphere bounces.

• On the first keyframe, drag the lead so that it is vertically above the keyframe. Do the same with the lead on the last keyframe. • Play the animation. The previ-ous adjustments cause the sphere to transition in and out of the first and last keyframes quicker, which gives the appearance of an abrupt change in direction. • Back to the Animation Edi-tor palette, select the middle key-frame and in the Key section (be-low the graph) choose Tangency Locked, Equal ( ). Extend one of the leads of the middle keyframe away from the keyframe (notice that the other lead extends equally). This makes the line formed at the middle keyframe look like an upside-down U. The middle keyframe corresponds to the upper end of motion of the sphere and the change we just made will make the sphere appear that it is hanging in the air a moment longer.

• From the Animation Time Line palette, play the animation and observe the differences the changes you just made are causing.

The Animation Editor palette before adjusting any of its leads.

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In order to make the ball appear as though it interacts with the ground during the bounce, the sphere should be squashed as it bounces. Before we squash the sphere, however, we need to make the sphere contact the ground longer than it does currently.

• On the Animation Editor palette, with the Insert Keyframe tool ( ) active, click on time 60 (horizontal axis) and value 0 (verti-

The sphere after being squashed.

cal axis). • Adjust the new keyframe to have a Lead In type of Linear ( ). Do this by highlighting the key and in the Lead In section, click the Linear type (bottom of the palette). • From the Animation Time Line palette, play the animation. Notice that the sphere seems to hesitate or pause when it is in contact with the ground. This may look unnatural now, but will look right once the sphere is contracting and expanding during this time.

Adding a Scale Z track to the sphere.

Inserting a keyframe at 60, 0.

• In the Time Line pal-ette, set current time to 0. • In the Animation Edi-tor, right click the name of the sphere and select Add Tracks... from the context menu. This invokes the Add Tracks dialog, which contains a list of tracks that can be added to the active animated object (the sphere). • Select the Scale Z track and click OK to close the dia-log. If you now click on the tri-angle before the sphere name to expose its content, you see that it contains two tracks: Po-sition Z and Scale Z. • Go to the list of tracks on the left and click on the eye symbol ( ), in the sec-ond column of the Position Z row. This erases the eye symbol and the display of the graph for Position Z.

Advanced motion: squash and stretch

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If you are setting up an animation that is meant to cycle many times, you will want the first keyframe to have the same value as the last key-frame. This will make a smooth tran-sition between cycles.

The graph for the Scale Z track, in the Animation Editor palette should now look like the graph to the right.

• In the Animation Time Line pal-ette, click play. The sphere should now look as though it is being compressed when it hits the ground. We can ex-aggerate the rebound by making the sphere to actually expand beyond its normal shape when it touches the ground. • In the Animation Editor pal-ette, adjust the lead of the first key-frame so that it is pointing vertically. • Do the same with the Lead In for the second keyframe. • Set the Lead Out of the sec-ond key and the Lead In of the third

Adjusting the Leads for more realis-tic behavior of the sphere.

The Scale Z track in the Animation Editor palette.

• For Scale Z, there should be a keyframe at time 0. Set this first key-frame to a value of 0.7. • Insert the following keyframes at times and values: 20 and 1; 56 and 1; 58 and 0.5; 60 and 1. • Right click the Scale Z track and select Track Options.... Click on the After tab and from the menu under it select Repeat Normal. Also, check the Connect Beginning And End option. When you do, you notice that the last keyframe changes to the same value as the first, which is 0.7.

• Click on the Fit Visible ( ) button.

key to be Linear ( , ). Recall that you do this by selecting the second item from the respective menu below the graph.

• From the Animation Time Line palette, play the animation.

You notice now that, as the sphere leaves the ground, it stretches up. It re-turns to its normal shape as it approaches the top of its flight.

This can be taken a step farther and given some lateral scale that is inversely proportional to the vertical scale. In other words, as the sphere is compressed

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vertically, it should expand horizon-tally.

• Set current time to 0. • In the Animation Editor pal-ette, add two more tracks for Scale X and Scale Y. • Move the first keyframe of Scale X up to a value of 1.3 at frame 0. This is the point at which the sphere is squashed down at maximum com-pression.

The graph for the Scale X track.

The Paste Control Points Options dialog.

• Add a second key at frame 6 with value 0.6. This will cause the sphere to get thinner as it is rebounding up into the air, reinforcing its vertical motion. • Make two keys at frames 16 and 56 of value 1. The sphere is at a normal size during its flight. • Add a final key at frame 60 of value 1.3 to complete the cycle.

Scale Y will be identical to Scale X and will thus be constructed by copying and pasting all the keyframes from one track to the other.

• Select all the keyframes on Scale X. To do this, press ctrl (Macin-tosh) or shift (Windows) and click on the line for Scale X. This will select the entire animation curve. Select Copy from the Edit menu.

• Highlight Scale Y in the Animation Editor palette and select Paste from the Edit menu. As soon as you do, the Paste Control Points Options dialog appears.

• Change Remove Con-trol Points to All. This will de-lete all existing control points in the time span we specify. Leave Time Span at the de-fault Keep Same. Click Ok.

Now, Scale X and Scale Y should be the same. Right click each and select Track Op-tions.... Click on the After tab, from the menu under it select Repeat Normal.

Click play in the Animation Time Line palette to see the results of the animation.

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Animating Materials

In this tutorial, you will continue the previous one with the bouncing ball and you will assign colors to the ball and the floor, which change as the ball bounces.

There are two ways in which the color of an object can change over time. Remembering that colors in form•Z are handled with materials, one way of changing color is to switch from one material to another at appropriate times. The other way is to animate the individual parameters of the materi-al itself. This tutorial will cover both methods of changing an object color.

You can continue using your own file, that is, the one you saved in the pre-vious tutorial session, or you can open the one we provide and continue working with this. It is called "Surface Styles Base." Here is what you will find in the new file or, if you continue your own file, here is what you should add, before you proceed: (1) A roughly 40' x 40' rectangle (surface object) in the middle of the XY reference plane representing the floor on which the ball is bouncing. (2) Four materials labeled green, yellow, red,

The bouncing ball and its floor.

and floor. The first three have plain colors corresponding to their names. The fourth is the Checker color shader with its default settings and uses two shades of blue to color the tiles of the checker pattern. The floor material is currently assigned to the floor rectangle and the ball is colored green. You may produce a (static) RenderZone rendering to confirm that this is in fact the case, which will look like the ex-ample to the right. The rendering is a perspective view and uses two Distant lights at their default intensity, with Shadows on and Per Light. Needless to say that, since this tutorial is not about rendering, you should render it according to your preferences.

A RenderZone rendering of the ball and its floor.

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Animating the color of the ball

• From the Animation Time Line palette, play the animation to confirm that it is still in place.

Your next task is to make the bouncing sphere change color at each bounce. • In the Animation Time Line palette, set current time to 0. • Open the Animation Editor palette and in its list right click the sphere name. • Choose Add Tracks... from the context menu. In the Category pop up menu, select Object Attributes. • Highlight Material and click OK to exit Add Tracks. • In the Animation Time Line palette, set current time to 60 frames. • In the Materials palette, set the active color to yellow and, with the Paint tool ( ) active, click on the sphere. • In the Animation Time Line palette, with the mouse, move the current time between roughly 1 and 3 seconds. Observe that the sphere is not only moving in space, but its color is also changing from green to yellow. • In the Animation Time Line palette, set current time to 120 frames. • Set the active color to red and, with the Paint tool ( ) active, click on the sphere. • Open the Animation Editor palette and highlight the sphere's Mate-rial track. • Use the Insert tool ( ) to add another keyframe at frame 180 and value red. • Right click the Material track and select Track Options.... Click the After tab and from the Type menu select Repeat Normal.

The Animation Editor palette and its graph should now look like the ex-ample below. From the Animation Time Line palette, play the animation and observe how the ball changes color as it bounces.

The Material graph in the Animation Editor palette.

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Animating the color of the floor

Next, the color of the floor object will be set up to change smoothly over time. This will be done by animating shader parameters, which is the sec-ond method available for changing the color of animated entities.

Before you proceed a little warning. You will only be able to see the effects of your manipulations after you render your animation, at the end of the session. That is, you will not be able to preview your settings while they are still in progress, as you were able to do with the previous animations. The reason is, of course, that you will be animating parameters of procedural textures, which are only available in RenderZone and not in Open GL.

• In the Animation Time Line palette, set the current time to frame 60. • In the Materials palette, dou-ble-click on the Floor shader to in-voke the Material Parameters pal-ette. In it, you notice that Checker is displayed for Color shade. Click

The Checker Options dialog.

the Options... button next to it, to invoke the Checker Options dialog. • Click on the red dot in the top left corner of the Color 2 box. From the menu that pops up, select Add Track. • Click OK to return to the Material Parameters palette and then close the palette to return to the modeling window. • Open the Animation Editor palette and in it highlight the Color 2 parameter of the animated Material. • Use the Insert tool ( ) to add a key for Color 2 at frame 70 with the same value as the first keyframe. Close the Animation Editor palette. • In the Animation Time Line palette, set the current time to frame 120. • Double-click on the floor material to open the Material Parameters palette. In the Color section, click the Options... button to invoke the Checker Options dialog. • Click on the box for Color 2 and when the Color Picker dialog ap-pears, change the color to yellow, or to some color you may prefer, other than blue. • Click OK to close the Checker Options dialog and close the Material Parameters palette to return to the modeling window. • Open the Animation Editor palette and use the Insert tool ( ) to add another keyframe at frame 170 with the same value as the original value of Color 2. • Add another keyframe at time 180. • Right click the track in the graph and select Track Options.... • Click the After tab and for Type select Repeat Normal.

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The Material graph in the Animation Editor palette.

• Click the Before tab and for Type select Repeat Normal.

Before proceeding with the final stage of this animation, which is the ren-dering, observe the displayed Animation Editor palette and how the ac-tual colors are displayed with the vertical value axis.

You could have actually changed the color from the Animation Editor palette, rather than going to the Checker Options dialog, which you did a bit ago. If you double click on a color box of the value axis you will invoke the Color Picker dialog, where the color can be changed.

Rendering the animation

• From the Display menu, select Generate Animation.... • When the Animation Generation dialog is invoked, set the desired rendering and other parameters. One of the settings in the dialog is about which rendering mode you will use. You can experiment with different ones, but for this tutorial select RenderZone, whose options should already be set from the still rendering you did at the beginning of this session. If not, you can do it now. Once your settings are in place, click the Generate Anima-tion... button (not the OK button).

form•Z proceeds immediately and executes the rendering one frame at a time. You are kept informed about the total number of frames to be ren-dered and which frame is currently being rendered. How fast the rendering will proceed depends, of course, on the usual factors, such as number of frames, the rendering effects, and the size of the frames. For this example, you may actually want to reduce the size of your frames, which is done from the Image Options dialog, invoked from the Display menu.

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When the rendering is completed, the animation is saved according to the settings in the Animation Generation dialog. The defaults will be to save all the frames in one file and in the form•Z animation format (.fan). The .fan file can be played back by selecting the Play Animation... item in the Display menu.

Once you have a .fan file you can also generate a QuickTime movie, as follows:

• From the File menu select Export Animation... and, when the Open file dialog appears, locate the .fan file and click Open. • When the Animation Frame Export Options dialog appears, click OK; when the Save file dialog appears, set the place and the name of the QT movie, also make sure Quick Time Movie is selected for File For-mat and click OK; when the Compression Settings dialog appears, click OK.

After a few minutes, a QT movie is generated and stored where you told it to. Play it.

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Animating lights and cameras

Lights and cameras can be animated just like any object. However, they typically have more parameters that can be animated. For example, in the case of lights, their intensity can be animated, but also their location and their center of interest can be animated separately. The same is true for animated views, which are also called cameras.

This tutorial will cover mostly parameters of lights and cameras that are unique to these types of entities. A light and a camera will be animated in a way such that their location and center of interest move independently of each other. These entities will be applied to a variation of the scene with the bouncing ball that you worked with in the previous two sections.

Again, you may continue with the file you saved at the end of the "Bounc-ing Ball" section or you may open and use a new file that we have set up for this exercise. It is called "Lights and Cameras Base." In addition to the bouncing ball, the following is what is new in this file:

The scene in a Shaded Work per-spective view.

(1) A 10' high brick wall that delin-eates part of a room. (2) A gray surface for the floor. (3) Three surface styles: a yellow for the ball, rough gray for the floor, and a procedural brick texture for the wall. (4) Two lights, one of which is a cone light that will be animated. (5) Two saved views, one of which is a perspective camera that will also be animated. These entities are shown to the right.

• Next, in the Views palette, se-lect the preset view called "main view" and from the Display menu select RenderZone.

You can observe the cone light that is shining on the scene and is currently stationary. The view of the scene is also stationary. You will first animate the camera to slowly pan by the scene, while it remains focused on the bouncing ball. The scene rendered in perspective

view.

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Animating the camera

• In the Views palette, verify the Visibility of "main view" is on. • From the Views menu, select Top. • Right click on the Fit All tool ( ) and select Zoom Options from the context menu. In it, turn on Include Lights. • Click on the Fit All tool ( ). All the visible entities of your proj-ect, including lights, are now dis-played on the screen. • In the Lights palette, click the visibility icon ( ) next to the cone light to ghost it or to even make it completely invisible. • Make sure the time is at 0 in the Animation Time Line palette. • With the Keyframe tool ( ) active, click on the camera. • Move the current time ahead to 5 seconds. • Make sure the AutoKey ( ) option is on.

Top views (a) before and (b) after the camera is animated and moved.

• With the Move tool ( ) active, click on the eyepoint end of the view and drag it up to another location in the scene. • In the Views palette, make "main view" active and, in the Animation Time Line palette, click on the Start ( ) button to set the time to 0. • Click the Play ( )button. Observe how the whole scene rotates as it follows the motion of the animated camera.

You will next adjust one of the parameters of the camera.

• Open the Animation Editor palette. • Highlight the Focal Length track of the animated "main view." • You may want to turn off the visibility for all the other items except for focal length. This will hide them and make it easier to work with focal length. • With focal length highlighted, use the Insert tool ( ) to add a key-frame at 5 seconds. • Adjust the value of this keyframe to 70. Highlight the focal length curve in the graph and click the Flat button ( ).

a

b

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• Click on the Fit Visible icon ( ). The graph in the Animation Edi-tor palette should be as shown in the example below.

Close the Animation Editor, play the animation, and note how the camera is zooming in.

Animating the cone light

You will next animate part of the cone light so that, while its location re-mains stationary, its focal point (or center of interest) follows the motion of the ball. You will actually do this by copying the animation setting for the ball to the center of interest track of the light.

• Stop the animation if it is still running. • In the Animation Time Line palette, set the current time to 0. • In the Lights palette, make the cone light visible again, if you turned it off earlier. • Activate the Keyframe tool ( ) and click on the cone light. • Open the Animation Editor palette and turn on visibility ( ) for the Position Z track of the bouncing ball. This will make the track visible. • Select the entire Position Z track by clicking on its curve in the graph while pressing ctrl (Macintosh) or ctrl + alt (Windows). • Once the line is selected, from the Edit menu, select Copy. Or you can press cmd+c on the Macintosh or ctrl+c on Windows. • Highlight the Center of Interest Z track for the cone light. • From the Edit menu select Paste or use the key commands cmd+v (Macintosh) or ctrl+v (Windows). • When the Paste Options dialog is invoked, click OK to accept the

The Animation Editor palette after the insertion of a keyframe for focal length.

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default settings. • While the Center of Interest Z track is still highlighted, click the After tab and from the Type pop up menu select Repeat Normal. • In the Animation Time Line palette, click Play.

The center of interest of the cone light should now be constantly moving and is aiming at the bouncing ball.

You will next animate one of the parameters of the cone light so that its lighting transforms from a concentrated light effect to a more diffused light-ing.

• In the Animation Time Line palette, set the current time to 0. • From the Palettes menu, open the Animation Editor palette. • In it, right click the cone light and choose Add Tracks... from the con-text menu. • In the Add Tracks dialog that is invoked, from the Category menu, se-lect Cone. From the list of Available Track Types that is displayed select Outer Angle. • Click OK to exit the Add Tracks dialog. • Highlight Outer Angle in the Animation Editor. • Activate the Insert tool ( ) and add a key 5 seconds with a value of 50. • Click on the Fit Visible icon ( ).

The graph in the Animation Editor palette should similar to the example below.

The Animation Editor palette after copying the motions of the ball to the cen-ter of interest of the cone light.

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While "main view" is active in the Views palette, from the Animation Time Line palette, play the animation to preview how the cone light behaves. You may also observe your animated entities from a distance. To do this, select the "axo view" in the Views palette and play the animation again.

The Animation Editor palette after the insertion of a keyframe for outer angle.

You can finally render your animation to watch the results of the tutorial. Before you do, make sure you select "main view" again. Then, from the Display menu, select Generate Animation... and watch the frames being rendered one at a time.

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Animating parts of objects

One can animate individual points, segments, outlines, or faces of ob-jects. In this tutorial, you will animate points. In the first part, which will illustrate the use of the Keyframe tool ( ), a flat roof will be reshaped into a gable roof and then a hipped roof. In the second part, which will illustrate the use of the Animate along Path tool ( ) for animating parts of objects, the apex point of a pyramid will be moving about a circle.

Keyframing Points

First build a block with the Cube tool ( ), the size does not really matter.

Next, turn Snap to Point ( ) and Snap to Interval ( ) on.

Use the Offset Segment tool ( ) to select one of the top segments and drag inward, snapping to the midpoint as shown in example (b).

The points that are a part of the top of the object need to be keyframed and then animated.

• Select the Pick ( ) and in the tool options make sure Points ( ) are

a

b

c

selected. Choose the two points at the end of the segment you just cre-ated. • With time set to 0 in the Animation Time Line palette, activate the Keyframe tool ( ) and click in the project window. • In the Animation Time Line palette, move the time to 2 seconds. • The two points should still be selected.

• With the Move tool ( ) active, click and move the two points upwards 5’ by toggling the perpendicular switch, Cmd (Macintosh) or Ctrl (Windows), shown in example (c).

If you play the animation, the block is now forming a gable roof as it approaches the 2 seconds mark.

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Animating points.

Choose the Offset Segment tool ( ), se-lect the bottom segment and drag upward, snap to either of the points at the bottom of the roof as shown in example (d). To do this you need to go to the modeling workspace.

You will next move the points some more to form a hipped roof. • Set the time to 4 seconds. • With the Pick tool ( ), select the 2 points on the top of the roof. • With the Independent Scale tool ( ) click the midpoint between the 2 selected points, next click on one of the 2 selected points and drag inward about 7' (as shown in example e).

Rewind the animation and click Play to watch how your block changes shape dynamically and becomes first a gable and then a hipped roof.

d

e

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Animating point along a path

Open a new project so that you can start fresh.

• Draw a pyramid using the Rectangle tool ( ) with 3D converged ( ) set in the tool

options. Then, working from a Top view, draw a circle that preferably touches the points of the pyramid (even though it is not an absolutely nec-essary condition). • With the Break tool ( ), click on the circle where marked with a bullet in example (b). This turns the circle into an open arc. • Working in Front view, move the circle from the base of the pyramid to the height of its apex, as shown in example (c).

You now have the objects you need to animate a point along a path.

Animating a point along a circle.(a) Original objects. (b) Initial keyframe.(c) (d) Animated instances at two times.

• With the Animate along Path tool ( ) active, Cmd (Macintosh)or Ctrl (Windows) click on the apex point of the pyramid and then on the circle.

The apex point of the pyramid jumps to the point where the circle was bro-ken and this shape of the pyramid becomes a keyframe.

• From the Animation Time Line palette play the animation and observe how the apex moves around the circle continuously.

a

c

Drawing a pyramid and a circle.

a

b

c

In a similar fashion segments, outlines, and faces can be animated along paths, except that the entities at these other topological levels are sensitive to the alignment options that are set in the Animate Along Path Tool Options palette.

You should experiment on your own with animations of parts of object at topological levels other than point.

b

d

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Animating deformations or dancing board

Objects can be made to alter their shapes over time, using the Animate Deformation tools. This tutorial will demonstrate some of the features of the Animate Deformation tools, while creating an animation of a board doing a backflip.

Open the "Deformations Base.fmz" file that can be found in the tutorials folder on your program DVD or our website. After you open it, play the animation. You observe that a board is already animated to do a backflip. However its shape does not change, which you will do next. Before you do, you may also want to take a look at the Animation Editor palette to see what tracks have been animated. If the tracks are not visible, turn on visibility ( ) in the second column.

The Animation Editor palette when the "Deformations Base.fmz" file is opened.

The board in the file.

You will first create the animated deform entities that will be used in the animation. • Switch Workspaces to Rendering/Animation. • Activate the Animate Bulge Deformation tool ( ) and in the Tool Options palette, set Model Type to Facetted, drag the Density slider all the way to the right, and make sure the Base Reference Plane menu is set to Object (XY). In the Time section, set the End time to 1.5 seconds. Below that, click the End tab, set the Anchor Scale X value to 0 and the Anchor Scale Y value to 35. • With the Animate Bulge Deformation tool ( ) still active, click on the board object (assuming it is not already selected. This creates an animated deformation entity in the project. • Activate the Animate Radial Bend Deformation tool ( ) and in the Tool Options palette, set Model Type to Facetted, drag the Density slider all the way to the right, and make sure the Base Reference Plane menu is set to Object (XY). In the Time section, set the End time to 4.5

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seconds. Below that, click the End tab, set the Angle value to 0 and the Spin value to 0.

• With the Animate Radial Bend Deformation tool ( ) still active, click on the board object.

This creates one more animated deformation entity, which is a radial bend entity. The previous one was a bulge entity. You will next observe these entities in the Animation Ed-itor palette.

• Open the Animation Editor palette. The Bulge(Object) and Radial Bend(Object) are displayed at the end of its list as in example (a) .

For these two deformations to work and affect the object, they need to be nested, which you will do next.

• In the Animation Editor pal-ette, drag the board object into the Radial Bend entity. • Next, drag the Radial Bend en-tity into the Bulge entity.

After you open the Bulge and Radial Bend entities, the list in the Anima-tion Editor palette should be as in example (b).

The bulge deform will be used to ex-aggerate the squashing of the board as it warms up before attempting a backflip.

• Turn the visibility ( ) off for all tracks except the Anchor Scale Y track under Bulge. • Now use the Insert tool to add the following keyframes, where the numbers are for Time and Value, in this order:

The Animation Editor palette (a) before and (b) after the deformations

were nested.

Frames from the deformation.

a

b

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The Animation Editor palette after new keyframes were added to the Anchor Scale Y track. (a) The Anchor Scale Y track only and (b) all the tracks.

a

b

3 and 0; 3.7 and 0; 4.3 and 60; 4.9 and 0.

• Play the animation to see the results of the bulge deformation.

The track with the new keyframes in the Animation Editor palette are shown below.

The Radial Bend deformation will be used next to make the board flex as it flies through the air and then make the board bend forward as it flips through the air.

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• In the Animation Editor palette, turn visiblity off for all tracks except the Angle track of the Radial Bend. • Highlight the Angle track and add the following keyframes:

5 and -25; 5.7 and 115; 5.9 and 115; 6.4 and 30.

• Play the animation. Observe how it bends backwards as it begins its jump and how the board bends in the air, landing on the ground slightly bent.

Some frames of the new deformations and the graph of the Angle track are shown below.

Lastly, you will make the board stand straight after landing, take a bow, and stand straight again.

Frames of the new animation.

The Animation Editor palette after new keyframes were added to the Angle track.

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• Open the Animation Editor palette and in it highlight the Angle track of the Radial Bend. • With the Insert tool add the following keyframes:

6.7 and 30; 7.2 and 0; 8 and 0; 8.6 and 90; and 9.2 and 0.

• Play the animation.

Some frames of the new deformations and the graph of the Angle track are shown.

The Animation Editor palette after more keyframes were added to the Angle track.

Frames of the new animation.

Concluding, we recommend that you experiment further with your own set-tings.

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A movie within a movie

Movie files can be used as texture maps for any of the four shaders of a material, namely Color, Reflection, Transparency, or Bump. The prac-tical implication of this is that prerecorded movies can be included in an animation and run within it. This tutorial will show you how to load a movie file as a color map. It will also show you how to set up the rate at which the movie will play.

Two television sets.

• Open the file "Color Maps Base," which contains the models of the two television sets. • In the Animation Time Line palette set current time to 0. • In the Material Parameters dialog, double click on the “tv tube” material and when the dialog ap-pears, from the Color menu, select Color Map. • Then click on the Options... button next to it. • In the Color Map Options dialog, click on the Load... button. • When the Open File dialog appears, select "spaceman.mov," the Quicktime file supplied with the tutorial.

Actually, you can select any .mov file you may prefer, including one you may have rendered for one of the tutorials you did earlier. • In the Frame Time field of the still open Color Map Options dialog,

The Color Map Options dialog after "spaceman" was selected.

enter 0, then press on the red dot next to it and, from the menu that pops up, select Add Track. • Make a note of the Duration of the movie, shown a couple of lines above Frame Time. Then click OK to exit the Color Map Options dialog, and then close the Material Parameters palette. • In the Animation Editor palette, find and highlight the track called "Frame Time." • In the graphic area, add another keyframe

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with the Insert tool. • Set its value to 3 and time to 3. • Make the leads of the animation track Linear and close the Anima-tion Editor palette.

The Animation Editor palette with the graph for "Frame Time."

Your model should be viewed in Shaded Work mode and the spaceman should appear on both TVs.

• From the Animation Time Line palette, play the animation. You should see the movie playing to both TV screens. Since the movie is a "texture" that is associated with a material, it will play on all the surfaces where the material is used.

You will next apply some motion to one of the TVs, so that the movie plays while the TV is rotating.

• Select all the objects that make up the model of the plasma screen. • Set current time to 0. • Select the Animation Group tool ( ) and in the Tool Options palette, turn on Center Of Bounding Volume. • With the Animation Group tool ( ) active, click on the project window. • Open the Animation Editor palette and in it right click the animation group just created. • Choose the Add Tracks button from the context menu and add a Rotation Z track. • In the Animation Editor palette, highlight the Position Z track and, with the Insert tool ( ), add a keyframe at 2 seconds and a value of 45° higher than the first keyframe. • Add a third keyframe at 4 seconds with a value equal to the first key-frame.

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• Select the entire motion track, which you do by clicking on it while pressing ctrl (Macintosh) or ctrl+alt (Windows). • Make all the leads of this track flat by clicking the Flat button ( ).

The graph should now be as shown below.

The plasma screen TV will now rotate back and forth and play the movie at the same time. Play the animation as before to verify this.

Finally you may render the animation by selecting Generate Anima-tion... from the Display menu and using RenderZone for rendering mode.

The Animation Editor palette with the graph for the Position Z track.