Advanced Computer Graphics Spring 2005

1
Advanced Computer Graphics
(Spring 2005)

• COMS 4162, Lecture 1 Overview
• Ravi Ramamoorthi

http//www.cs.columbia.edu/cs4162
2
Goals

• Systems Write fairly complex programs for image
  processing, mesh algorithms, image synthesis
• Theory Understand mathematical aspects and
  algorithms underlying modern 3D graphics Fourier
  analysissampling theory, mesh geometric data
  structures, Monte Carlo rendering, integration
• This course is a continuation of COMS 4160, intro
  graphics. It fills in some of the gaps there,
  and provides a more advanced thorough overview

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Course Outline

• 3D Graphics Pipeline

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Course Outline

• 3D Graphics Pipeline

Rendering (Creating, shading images from
geometry, lighting, materials)
Modeling (Creating 3D Geometry)
Unit 1 Foundations of Signal and Image
Processing Understanding the way 2D images are
formed and displayed, the important concepts and
algorithms, and to build an image processing
utility like Photoshop Weeks 1 3. Assignment 1
due Feb 15
5
Course Outline

• 3D Graphics Pipeline

Rendering (Creating, shading images from
geometry, lighting, materials)
Modeling (Creating 3D Geometry)
Unit 1 Foundations of Signal and Image
Processing Understanding the way 2D images are
formed and displayed, the important concepts and
algorithms, and to build an image processing
utility like Photoshop Weeks 1 3. Assignment 1
due Feb 15
Unit 2 Meshes, Modeling Weeks 4 6. Ass 2 due
Mar 10
6
Course Outline

• 3D Graphics Pipeline

Rendering (Creating, shading images from
geometry, lighting, materials)
Modeling (Creating 3D Geometry)
Unit 1 Foundations of Signal and Image
Processing Understanding the way 2D images are
formed and displayed, the important concepts and
algorithms, and to build an image processing
utility like Photoshop Weeks 1 3. Assignment 1
due Feb 15
Unit 3 Ray Tracing Weeks 7 9. Ass 3 due Apr
12
Unit 2 Meshes, Modeling Weeks 4 6. Ass 2 due
Mar 10
Unit 4 Advanced Topics Weeks 10. Ass 4 (final
project) due May 2
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Logistics

• Website http//www1.cs.columbia.edu/cs4162 has
  most of information (look at it)
• Office hours after class (or just send me
  e-mail)
• TA Bo Sun, CEPSR 615
• Course bulletin board to be set up, class TA
  e-mail cs4160_at_cs.columbia.edu
• TA office hours etc after next week of lectures
• Textbook Computer Graphics Principles and
  Practice by Foley, van Dam, Feiner, Hughes

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Workload

• Challenging course Lots of fun, rewarding but
  may involve significant work (like 4160, perhaps
  more understanding, a little less actual code)
• 4 programming projects. All are significant
  effort, real systems. Also require well
  documented reports (websites). Challenging but
  fun
• But most of you built games. I dont think
  workload substantial relative to that
• You have 3-4 weeks. Project scope assumes you
  actually work on them for 3-4 weeks. START EARLY
  and work steadily.
• Groups of 2 quasi-required (you can work alone,
  but at your own risk)
• Assignments 1-3 also have written questions that
  test understanding of mathematical and
  geometrical concepts taught
• Also done in groups of 2 as for programming.
  Start early here too
• No midterms or finals
• Prerequisites COMS 4160 or equivalent intro to
  graphics
• Note some overlap possible for those who took
  intro graphics elsewhere. Have fun and relax on
  those parts, or go overboard
• Generously graded You did well in 4160, here to
  have fun, learn graphics. Dont really worry
  about scores and grades. Just do work, have fun

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Related courses

• COMS 4167, on animation Prof. Grinspun this
  semester
• Many 6000-level courses (e.g. COMS 6160 High
  Quality Real-Time Rendering taught by me last
  fall) if you are still here next year
• Part of Vision and Graphics track in BS and MS
  programs. Columbia Vision and Graphics Center
• Other related courses Computer Vision, Robotics,
  User Interfaces Computational Geometry,

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To Do

• Look at website
• Various policies etc. for course. Send me e-mail
  if confused.
• Skim assignments if you want. All are
  tentatively ready (except for assignment 1, which
  is released)
• Assignment 0, Due Jan 20 tomorrow (see website).
  Send e-mail to cs4162_at_cs.columbia.edu telling us
  about yourself and sending us a digital photo if
  possible (to put names to faces).
• Assignment 1, Due Feb 15. Start working on it
  next week, but for now, make sure you can
  download and compile
• Find partners for assignment 1 and possibly
  later. Does anyone need help? Any other
  questions?

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History

• Brief summary of course in context of history of
  field

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2D Graphics

• Many of the standard operations youre used to
• Text
• Graphical User Interfaces (Windows, MacOS, ..)
• Image processing and paint programs (Photoshop,
  )
• Drawing and presentation (Powerpoint, )

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Paint Systems

• SuperPaint system Richard Shoup, Alvy Ray Smith
  (PARC, 1973-79)
• Nowadays, image processing programs like
  Photoshop can draw, paint, edit, etc.

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Image Processing

• Digitally alter images, crop, scale, composite
• Add or remove objects
• Sports broadcasts for TV (combine 2D and 3D
  processing)

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Relevance to Course

• In 4160, didnt cover 2D at all
• But relevant broadly (not just for 2D), since
  ultimately 3D scene displayed as 2D image
• In 4162, we cover image processing and many
  photoshop functions assignment to write a
  mini-version

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Modeling

• Spline curves, surfaces 70s 80s
• Utah teapot Famous 3D model
• More recently Triangle meshes often acquired
  from real objects

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Relevance to Course

• Covered Bezier, B-spline curves for modeling in
  4160
• Will talk briefly about NURBS, surfaces in 4162
• Main idea is to talk about mesh processing algs.
• Will learn to represent, work with meshes
• Do mesh simplification, progressive meshes

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Progressive Mesh Movie
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Rendering 1960s (visibility)

• Roberts (1963), Appel (1967) - hidden-line
  algorithms
• Warnock (1969), Watkins (1970) - hidden-surface
• Sutherland (1974) - visibility sorting

Images from FvDFH, Pixars Shutterbug Slide ideas
for history of Rendering courtesy Marc Levoy
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Rendering 1970s (lighting)

• 1970s - raster graphics
• Gouraud (1971) - diffuse lighting, Phong (1974) -
  specular lighting
• Blinn (1974) - curved surfaces, texture
• Catmull (1974) - Z-buffer hidden-surface algorithm

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Rendering (1980s, 90s Global Illumination)

• early 1980s - global illumination
• Whitted (1980) - ray tracing
• Goral, Torrance et al. (1984) radiosity
• Kajiya (1986) - the rendering equation

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Relevance to Course

• We didnt talk about visibility algorithms in
  4160
• Nowadays, simple Z-buffer used OpenGL
• Discussed illumination and shading models
• And theory (but not practice) of global
  illumination
• In 4162, we will cover practical global illum.
• First, build a simple ray tracer
• Extensions/final project related to rendering

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Image Synthesis Examples
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Summary

• COMS 4160 covered basics of computer graphics
• Theory of transformations, curves, illumination
• Building complex interactive graphics programs
• COMS 4162 covers more advanced topics and fills
  in the gaps in 4160. Essential for full graphics
  intro
• 2D Image and Signal Processing (Fourier
  analysis)
• Mesh algorithms (Mesh geometric data
  structures)
• Ray Tracing (Monte Carlo sampling for rendering)
• Advanced Rendering and other topics