### 20041 Graphics Final Topics

Wednesday, 11/17/04
4 P.M. section (01), Exam is at 2:45 P.M. in Room: 70-1435
6 P.M. section (01), Exam is at 6:00 P.M. in Room: 70-3455
1. The OpenGL Graphics Pipeline
• What processes take place in the OpenGL graphics pipeline and in what order?
• Which coordinate system is used at each step?

2. 3-D graphics
• World to camera/eye coordinate transformation - why?
• Why are two coordinate systems generally used for 3-D graphics?
• How many pieces of info are needed to establish location of the camera/eye/viewing coordinate system, what are they?
• Which coordinate system are these pieces specified in?
• What are the 4 steps in world to camera/eye/viewing coordinate transformation and what is accomplished by each? (tinker toy exercise)
• Viewing Parameters: eye, look-at, up
• What is the function of each in establishing the camera/eye/viewing coordinate system?
• How are u, v, and n specified for the camera/eye coordinate system?
• What is the affect on image when each is altered? (homework 2)
• 3D Transformations: scale, rotate, translate
• What are the equations of transformation? the matrices?
• 3D Clipping
• When done in OpenGL?
• How are 2-D and 3-D clipping the same? How different? (compare and contrast)?
• How is the view volume specified: components/coordinates, i.e., what sets its boundaries? Which coordinate system specified in?
• How are clipping and hidden surface/line removal the same? How different? (compare and contrast)
• View Volume, Parallel (Ortho) vs Perspective Projection
• Which command is used to specify the view volume in OpenGL?
• Where is the view plane located?
• Which coordinate system is view volume specified in?
• Which equations of transformation are used for parallel and perspective projection? (equations, not matrices)
• How do the effects from the application of scale, rotate, translate differ when using parallel and perspective projection?
• What establishes the direction of projection for parallel/ortho projection?

3. Hidden Surface/Lines **
• Algorithms
• Object Space - Robert's Volume Intersection
• Image Space
• Depth (z) buffer
• Scan Line
• Warnock's area subdivision
• First level ray tracing
• List Priority Ordering
• Painter's
• BSP Trees (be able to create/traverse tree)
• Schumacher's GE Flight Simulator
• Know algorithms generally
• Know when done in the rendering pipeline
• How are sorting geometric shapes and coherence relavent to this topic

4. Light, Color, Shading (Rendering)
• Color
• Halftoning
• Issues in color
• Issues in rendering
• Light: diffuse, point source, reflection, the role of normals
• Shading: Constant, Gouraud, Phong
• Opacity, Transparency, Translucence
• Shadows
• Materials: How represented in OpenGL
• Fog: How represented/done in OpenGL
• Textures (Texture/Bump Mapping)
• Techniques (general descriptions)
• Ray Tracing
• Radiosity
• Photon Mapping
• Non-Photorealistic Rendering
• What is the role of normals in all of these?

5. 3D Modeling
• Fractals (general descriptions)
• Uses
• Methods
• Recursive Subdivision (with random displacement)
• Iterative Feedback Functions
• Iterative Function Systems (ignore)
• L Systems
• Others (general descriptions/what are we modeling with each?)
• Hierarchical Modeling and Animation
• Surface Modeling
• Splines
• Polygonal Meshes, roles of
• Vertex list representation
• Edge list representation
• Normals
• Parametric surfaces such as Bi-cubic Patches
• Blobs
• Subdivision surfaces
• Particle Systems
• Image-Based Modeling
• Morphing
• Volume Visualization
• Model Generation from images (Image-based modeling)
• Physically Based Modeling
• Constraint Based Modeling
• Behavioral Modeling
• Solid Modeling
• CSG
• Spactial Enumeration Schemes
• Sweeping

6. Parallel Graphics
• Why/when is parallel computing useful in graphics?
• Why/when are fractals, such as Mandelbrot/Julia set generation, and ray tracing candidates for parallelization?
** For further material on this topic see: "A Characterization of Ten Hidden-Surface Algorithms" by Sutherland, Sproull and Schumacker, Computing Surveys, March 1974

November 5, 2004