Hand-painted Animation with Intelligent Brushes Tom Van Laerhoven, Fabian Di Fiore & Frank Van Reeth {firstname.lastname}@uhasselt.be Hasselt University.

Hand-painted Animation with

Intelligent Brushes

Tom Van Laerhoven, Fabian Di Fiore & Frank Van Reeth{firstname.lastname}@uhasselt.be

Hasselt University - Expertise Centre for Digital Media

transnationale Universiteit Limburg

Belgium

CASA’08

CASA’08 Sep 1th - Sep 3th Tom Van Laerhoven

Goals

CASA’08 Sep 1th - Sep 3th Tom Van Laerhoven

• Enrich interactively created stylized images with procedural animation.

• Make animation techniques available to untrained users.

• Avoid steep learning process.

Approach

CASA’08 Sep 1th - Sep 3th Tom Van Laerhoven

• Physically-inspired interactive painting tool “AquaVerve”.

• Animated canvas with separate canvasfor each frame.

• Special-purpose “intelligent” brushes.

• Animated pigment.

• Show animation continuously.

Background

CASA’08 Sep 1th - Sep 3th Tom Van Laerhoven

• Commercial packages: Corel Painter, MoXi, ArtRage, Project Dogwaffle

• ‘Only’ provide digital equivalent of traditional painting.

• Literature

I/O Brush

[Ryokai et al. CHI04]

Easel

[Rozin 98]

Paint-Cam

[Rozin 98]

AntBrush

[Tzafestas 00]

AquaVerve

CASA’08 Sep 1th - Sep 3th Tom Van Laerhoven

• Interactive paint system

• Watercolour, gouache, impasto, …

• Physically & empirically-based paint algorithms, GPU impl.[Van Laerhoven et al. CASA05]

• Virtual brush design [Van Laerhoven CGI07]

Animated Canvas

CASA’08 Sep 1th - Sep 3th Tom Van Laerhoven

• Set of 8 – 16 canvasses.

• Animation is shown continuously.

• Need for specialized brushes.

canvas representation1024x768 simulation grid

Intelligent Brushes

CASA’08 Sep 1th - Sep 3th Tom Van Laerhoven

• Semi-autonomous brush: flame brush

User: Interactively paint stroke

System:Record:• brush reservoir• stroke trajectory• brush attributes

Intelligent Brushes

CASA’08 Sep 1th - Sep 3th Tom Van Laerhoven

• Semi-autonomous brush: flame brush

…

User: Interactively paint stroke

Automatically-drawn scripted variations

frame 0 frame 1 frame N

System:Record:• brush reservoir• stroke trajectory• brush attributes

…

undo

Intelligent Brushes

CASA’08 Sep 1th - Sep 3th Tom Van Laerhoven

• Semi-autonomous brush: flame brush

…

User: Interactively paint stroke

Automatically-drawn scripted variations

frame 0 frame 1 frame N

System:Record:• brush reservoir• stroke trajectory• brush attributes

…

undo

Intelligent Brushes

CASA’08 Sep 1th - Sep 3th Tom Van Laerhoven

• Moving-dab brush

• Paint dabs on successive frames

Intelligent Brushes

CASA’08 Sep 1th - Sep 3th Tom Van Laerhoven

• Steady brush

• Paint on all frames at once

• Erase animated strokes

Painting motionless background

Erasing animation

Animated Pigment

CASA’08 Sep 1th - Sep 3th Tom Van Laerhoven

• Secondary motion

• E.g., animate the observed thickness of a single pigment type in impasto paint layer

• Vibrant or waving paint textures

Single-out a pigment type in a mix

Pigment properties:• stickiness• clumping• weight• animation

Results

CASA’08 Sep 1th - Sep 3th Tom Van Laerhoven

• Camp fire• Semi-autonomous flame

brush

• Primary flames

• Smoke trail

• Moving-dab brush

• Secondary flames

• Steady brush

• Background

• Yellow pigment withvibrant flame-like motion

Results

CASA’08 Sep 1th - Sep 3th Tom Van Laerhoven

• Flowing water• Semi-autonomous water brush

• Blue pigment that exhibits soft waving motion

Conclusions & Future Work

CASA’08 Sep 1th - Sep 3th Tom Van Laerhoven

• Brushes & pigment enhanced with behavioral intelligence

• Enrich & animate interactively created images

• Within reach of every digital painter

• Future work

• Animation of stroke textures

• Extend intelligent brush set; more complex scripts

Thank You

Questions?

http://research.edm.uhasselt.be/tvanlaerhoven

CASA’08 Sep 1th - Sep 3th Tom Van Laerhoven