CS 413 Vector Graphics

Instructor:

Joe Michael Kniss
Ferris 301G
277-2967
jmk (at) cs.unm.edu
Office Hours: TTr 3:30-5:30

Info:

Official class web page:
www.cs.unm.edu/~jmk/cs413

Recommended Text

Ray Tracing from the Ground Up Kevin Suffern, ISBN 978-1-56881-272-4
Order this book online

Realistic Ray Tracing Peter Shirley and Keith Morley, ISBN 1-56881-198-5
Order this book online (currently on back-order)

Note: text is not required, but recommended for the class.

Description

This course covers the basic mathematics and design of ray-based graphics. Topics include ray tracing implicit surfaces and meshes, high dynamic range images, high quality sampling, material modeling, and effects. Students will write a complete working raytracer and produce realistic images. Students will also be encouraged to pursue high performance, parallel implementations and well engineered software.

Deliverables

Assignments must be delivered electronically. Only 1 late assignment will be accepted with full credit (must be in before the next assignment is due). Any other late assignments will incur a 10% penelty per day. Students must solve 3-4 extra credit parts to achieve an A in the class.

Content **

• Week 1
  • Introduction
  • Assignment 1: Viewer, due Jan 27.
    • Use OpenGL and Glut or Java and Swing to produce a simple image viewer.
    • Viewer must accept command-line parameters for size, camera, lights, etc...
    • Viewer must report pixel values under mouse when image is clicked on...
    • Viewer must report current state (size, camera...) in command line form when 'C' key is pressed
    • Viewer must display an image either read from file or generated by the program.
    • Extra credit 1: measure speed of image updates. (how fast can images be loaded?)
    • Extra credit 2: identify fastest method for image updates. (use GL extensions)
  • Basic math
  • Linear algebra
  • line/ray equation
  • ray-sphere intersection
  • ray-plane intersection
  • Software design issues.

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• Week 2
  • Basic math continued
  • Viewer, Tracer, Scene design

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• Week 3
  • Barycentric Coordinates and intro to lighting.
  • Viewing parameters (eye, at, and up)
  • Assignment 2: Math Review, due Feb 11
    1. Describe the basic properties (Associativity, Commutativity, and Transitivity Distributivity) of:
       • The inner (dot) product
       • The outer product
       • The cross product
    2. What other properties do these operators have?
    3. Derive the ray-plane intersection (set up and solve for t)
    4. Derive the ray-sphere intersection (set up and solve for t)
    5. Derive the ray-triangle intersection (set up and solve for t)
    6. Extra Credit: Derive:
       • the ray-cone intersection
       • the ray-disk intersection
       • the ray-cylinder (with cap) intersection
  • Assignment 3: Vanilla Ray Tracer, due Feb 12
    1. Please make a web page for this assignment and discuss your results there.
    2. Implement a basic ray-tracer.
    3. Objects should be shaded using the Phong model.
    4. Render these objects (z is up) (all in one scene):
       • Plane at [0,0,0], normal [0,0,1], diffuse color [.05, .05, 1], specular color [.2, .3, 1], specular power 3
       • Sphere at [0,0,1] radius 1, diffuse color [1, .05, .05], specular color [1, .9, .9], specular power 10
       • Sphere at [2,2,0.2] radius 1, diffuse color [.05, 1, .05], specular color [.9, 1, .9], specular power 30
       • Triangle [-1, -1, .02][2,-2,.02][-1.5,-1.5,1.5], diffuse color [1, 1, .05], specular color [1,1,.9], specular power 100
    5. Light is at [4,4,4], color [1,1,1]
    6. Eye [0,5,2], Look-at [0,0,0], Up [0,0,1]
    7. Image plane is at [0,4,2] (distance of 1 from eye), Dimensions 2x2 (width and height)
    8. Rendered image should be 512x512 pixels
    9. Indicate runtime and computer specs with each rendered image.
    10. Extra Credit
        • Implement shadows (test if light is blocked by other objects)
        • Implement reflective bounce (3 bounces)
        • Implement and discuss an optimization (with runtimes before and after)

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• Week 4
• Shading and tone mapping
• Intro to texture mapping.

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• Week 5
• BRDFs
• Assignment 4: Texture and Antialiasing, due Mar 3
  1. Texture the plane with a checkerboard pattern.
  2. Texture the red sphere with a map of the earth.
  3. Render the scene with 4, 16, 32, and 128 samples per-pixel.
  4. Discuss the method you use to sample the pixels
  5. Identify and illustrate the artifacts or improvements that anti-aliasing provides.
  6. Extra Credit 1 render the scene with new view points
  7. Extra Credit 2 make a movie of the the scene (moving through it) and compare different anti-aliasing methods

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• Week 6
• More BRDFs and Shader Models
• Assignment 5: Acceleration Datastructures, due Mar 12 extended to Mar 23. Turn it in on time for some extra credit!
  1. Implement a log(n) acceleration data structure for triangle intersections. (KD, BVH, or Octree)
  2. You must be able to load a .obj model.
  3. Provide timings before and after acceleration.
  4. Provide a detailed analysis of your ray-tracer's performance.

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• Weeks 7,8,& 9
  • Spectroscopy
  • Units and terms of light transport
  • Transparency
  • Glass and dielectrics

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• Week 10
  • More dielectrics
  • Fresnel terms
  • Snell's Law
  • Beer's Law
  • Assignment 6: Dielectrics, due Apr 16
    1. Implement glass in your raytracer
    2. Glass must support a Fresnel term
    3. Glass must support different indexes of refraction
    4. Glass must support different absorption terms
    5. Produce a sequence of 7 glass spheres (all in one scene), each with a different index of refraction. Make sure the background you choose makes the differences clearly visible.
    6. Render a model of your choosing as glass.
    7. Extra Credit Render a scene with nested glass objects, each with a different index of refraction.
    8. Extra Credit Experiment with different absorption terms for your glass, try to simulate a real-world object (such as different colored glass bottles).
    9. Discuss how you implemented the reflection/refraction ray pairs, and provide performance statistics with and without dielectrics.
• Week 11
• Procedural Methods
• Splines
• Noise
• Hacking!
• Extra Credit: Scripting, due April 29
• Take this tutorial on Bash scripting
• Write a script (or scripts) demonstrate the usage of:
  • Variables; declaration, usage, assignment, list/arrays
  • Logical Tests; And/or, exists, is zero, etc... (how many different tests can you do?)
  • If/then/elseif/else branching
  • Loops, there are several kinds, how many distinct ways can you loop?
  • Quoting, what's the difference between "$blah" and '$blah' ?
  • Subshells
  • Automated rendering (using your raytracer), e.g. Animation or variations of paraemters
• Final Project, due May 13
• Render an image or animation using a scene of your design in your raytracer
• Your rendering should demonstrate techniques developed in previous assignments
• Pay special attention to your use of color and composition
• Extra Credit: demonstrate a new rendering effect (e.g. photon mapping, environment mapping, novel shaders, etc...)
• You must include a brief writeup that includes details about the rendering methods you used, render times, and souces of content (i.e. where did you get your models, textures, maps, etc...)
• Image/Animation, code, and writeup must be submitted by the Due date for credit (no late assignments can be accepted).
  ** subject to change

  Resources

  • Code
    • A Basic C++ vector class
  • Data
    • High Dynamic Range images.
    • HDRShop is a tool for manipulating HDR images.
    • Earth Texture Map
    • CUReT BRDF Database
    • Cornell BRDF Database
    • Bonn BTF Database
  • Papers & Maths
    • Stochastic Sampling in Computer Graphics
    • Bicubic Interpolation (catmull-rom)
    • Fresnel Equations
    • Lambert's Cosine Law
    • Snell's Law
    • Beer's Law
    • The Rendering Equation, a derivation
    • Jim Arvo's Notes on Radiative Transfer
    • Ken Perlin's Image Synthesizer and his improvements.