CPSC 424 Exam 3 Review Information

Exam 3 will cover material from weeks 10-13 and Blender lab 4: animation techniques, particle systems, raytracing, path tracing, photon mapping, and radiosity. three.js won't be covered.

The exam will be written (not on the computer), with the focus on concepts.

You may have a single page of notes (8.5x11", one side) which will be handed in with your exam. This page may be handwritten or typed and can contain whatever you would like, but it must be a hardcopy — on a piece of paper, not a laptop, tablet, phone, or other device — and must be personally prepared by you — you may not copy another student's page or hand out copies of yours to others. Creating your own notes is an essential part of the learning process — deciding what to include requires engagement with the material which reinforces understanding and improves long-term retention of the material, provides an opportunity for review in order to identify gaps in your knowledge in time to ask questions before the exam, increases confidence in what you do know, and encourages taking ownership of your own learning.

Specific topics, terms, and concepts you should be familiar with:

• animation

  • terminology: modeling and rigging
  • the 12 principles: the overall idea and their purpose, the specific principles discussed in class (what they are, how they contribute to a successful animation)
  • techniques: keyframing, explicit scripting, kinematics, motion capture, dynamics, behavioral animation
    • for each technique: what it is, pros and cons
    • keyframing: linear interpolation, alternatives to linear interpolation, keyframing for articulated structures
    • forward vs inverse kinematics
    • forward vs inverse dynamics
    • behavioral animation: simple boid model, terminology (desired velocity, steering vector, neighborhood), examples of steering behaviors, methods of combining steering vectors and their pros/cons

• particle systems

  • what particle systems are good for, when it might be appropriate to use a particle system
  • the main loop, and what each step in the loop accomplishes
  • typical attributes of particles
  • the idea of emitters, and how initial values for each particle are assigned
  • how hierarchical particle systems work
  • what structured particle systems are, and what they are good for
  • rendering non-solid objects such as fire
  • rendering solid objects such as trees or grass
  • how the Genesis Effect was achieved (particle generation, particle extinction, particle rendering)
  • how trees can be modeled with particle systems, including rendering
  • how wind can be modeled with particle systems

• raytracing

  • how raytracing works: the recursive raytracing algorithm, including when to stop tracing rays and the minimum depth needed for reflection and refraction
  • handling shadows
  • what coordinate system(s) are used and why
  • what raytracing is good for, its pros and cons / advantages and limitations
  • characteristics of raytraced images

• global illumination methods

  • the rendering equation (the big picture, in words)
  • what the principles of global illumination, equivalence, and direction are
  • terminology: BSDF, BRDF, BTDF (what each acronym stands for and what the term means)
  • compare and contrast OpenGL materials and BSDF materials
  • how the notion of a BSDF can support materials like fog and clouds and effects like subsurface scattering
  • compare and contrast path tracing, photon mapping, radiosity in terms of their approaches, their effects on the rendered image, their pros and cons
  • compare and contrast the polygon pipeline, raytracing, and global illumination methods (path tracing, photon mapping, radiosity) in terms of their approaches, their effects on the rendered image, their pros and cons

• path tracing

  • what it is (the algorithm)
  • what it is good for, its pros and cons / advantages and limitations
  • volumetric path tracing

• photon mapping

  • what it is (the big picture idea of photon mapping)
  • what it is good for, its pros and cons / advantages and limitations
  • implementation at the algorithm level: what the two passes are, how the photon maps are created and used, what elements of the scene lighting are captured
  • what caustics are, and how photon mapping supports them
  • characteristics of photon-mapped images

• radiosity

  • what it is (the big picture idea of the radiosity approach)
  • what the term "radiosity" means
  • what it is good for, its pros and cons / advantages and limitations
  • what goes into the radiosity equation, including being able to write down the equation for the radiosity of a particular surface patch given information about form factors, reflectivity, and emission
  • the gathering and shooting methods for solving the radiosity equation, the pros and cons of each
  • what progressive refinement is and why it is used instead of just solving the system of radiosity equations directly
  • what importance-driven radiosity is, its pros and cons
  • what a form factor is, and what factors go into its computation (at the concept level — you don't need to give the formula)
  • combining radiosity and raytracing — why and how