1/12/09 1 Introduction Computer Graphics COMP 770 (236) Spring 2009 Instructor: Dinesh Manocha.

1/12/09 1

Introduction

Computer GraphicsCOMP 770 (236)Spring 2009

Instructor: Dinesh Manocha

1/12/09 2

Welcome to COMP 770 (236)

■ Instructor: Dinesh ManochaEmail: [email protected]: Brooks 250Office hours: W 1:00–2:00 (or by appt.)

■ Webpage: http://www.cs.unc.edu/~dm/UNC/COMP236/comp236.html

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About you

■ Name

■ Your background

■ What are you studying?

■ Previous graphics experience

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Prerequisites

■ COMP 665(235)° Displays and 2D Graphics

° Pixels, lines, images

° Foundations of 3D Graphics° Points, vectors, matrices, transformations

° Foundations of image analysis° Sampling, reconstruction, aliasing

° Foundations of computer vision° Eye, color, perception

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Prerequisites

■ COMP 575(136)° Basic graphics pipeline° Transformations, clipping, rasterization° Texture mapping° Ray tracing° Hidden surface removal

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Prerequisites

■ Know a programming language in the C family (C / C++ / C# / Java / Python)

■ Some familiarity with graphics API (OpenGL or DirectX)

■ Can use any platform (Windows, Mac or Linux)

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Computer Graphics: Overview

Modelling Simulation &Rendering

Image

Computer vision inverts the process

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Topics

■ Mathematical tools■ 3D models and

interaction■ Visibility■ Rasterization■ Lighting and shading■ Shadows■ Texture mapping

■ Ray tracing ■ Global illumination ■ Curves and surfaces ■ Simplification and levels

of detail■ Graphics hardware ■ Solid Modeling

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Mathematical tools

■ homogeneous coordinates

■ vectors■ planes■ frames■ transformations

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3D models and interaction

■ Loading and view models■ Picking and selection■ Modeling a trackball■ VR is all about interaction

COMP 872

a

b

axis

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Visibility Computations

■ Classic problem■ BSP trees■ Ray casting■ Depth buffering

Images courtesy of Cornell University

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Rasterization

■ Clipping

■ Scan conversion

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Lighting and shading

■ Flat, gouraud, and phong shading

■ Empirical and physically-based illumination models

■ BRDFs

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Shadows

■ Shadow volumes■ Shadow maps■ Soft shadows

Umbra Penumbra

Images courtesy of Stamminger and Drettakis 02

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Texture mapping

■ Surface parameterization

■ Mipmaps and filtering■ Reflection and

environment mapping

Images courtesy of Jeremy Birn (www.3drender.com/jbirn)

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Ray tracing

■ Object intersection■ Reflection and refraction■ Depth-of-field, motion blur,

glossy reflections, soft shadows

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Global illumination

■ Rendering equation ■ Path tracing, photon

mapping, radiosity■ COMP 870 Advanced

rendering

Images courtesy of Caligari (www.caligari.com)

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Curves and surfaces

■ Bezier curves and B-splines■ NURBS and subdivision

surfaces■ Parametric solids■ COMP 767 Geometric and

solid modeling

1-level0-levels 2-levels

3-levels

4-levels

5-levels

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Solid Modeling

■ CSG and B-Rep operations■ Generating complex solids

from simple shapes

■ COMP 767 Geometric and solid modeling

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Simplification and LOD

■ Levels of detail ■ Progressive meshes

82 million triangles

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Graphics hardware

■ History■ Architecture■ Shading languages■ Now:general purpose

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Animation & Simulation (less or no coverage)■ Keyframing■ Parameteric splines■ Motion capture■ Simulation■ COMP 768

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Textbook

■ No official textbook. Here are some possible references:

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Textbook

■ No official textbook. Here are some possible references:

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Textbook

■ No official textbook. Here are some possible references:

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Course Grading

■ Problem assignments & class participation (50%)

■ Midterm: 20%

■ Final Project: 30%

■ Guest lecture on a topic (optional): 10%

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Grading

■ Assignments: 40%Final project: 30%Class participation

1 midterm: 30%

■ Late policy: Assignments will lose 5% each day late (M-F)

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Course Project

■ Start thinking about a project idea ASAP

■ Should have some novelty

■ Ok to combine with RAship or other course projects

■ Project proposal due by Feb. 23, 2009

■ Periodic updates

■ Final project presentation (during finals week)

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Honor Code

■ Students are here for the learning not the grade.

■ Collaboration encouraged, but assignments must be your own work.

■ Cite any other’s work if you use their code.

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About your instructor

■ Have been at UNC for 16+ years

■ Research in geometric/solid modeling, real-time rendering, graphics hardware, simulation, ray tracing, sound rendering, crowd simulation, shadows

■ http://gamma.cs.unc.edu

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Next time: 01/14/09

■ Overview of graphics rasterization pipeline

■ Guest lecture by Paul Merrell