CS 445 / 645: Introductory Computer Graphics Review

Final Exam l Thursday, December 13 th from 7 – 10 p.m. –Room Olsson 011 l You may use one sheet of notes (8.5 x 11’’) –You can write on both sides of paper l Not everything from semester will be on test –Class on Thursday will outline material and review

Review l If you’re going to print out all the slides from my lectures, please try to keep our costs down. –Render multiple slides to a page. –Keep the amount of black ink down

Review Slide from Midterm l Hearn and Baker –Chapter 2 (NOT ON FINAL) –Chapter 3 (84-102, ) (NOT ON FINAL) –Chapter 5 –Chapter 6 ( ) (NOT ON FINAL) –Chapter 11 (No Quaternions) (FINAL WILL INCLUDE QUATS) –Chapter 12 ( ) –Chapter 14 –Chapter 15 –Appendix 1 – 4 l OpenGL Red Book –Chapter 1 - 3

Review Since Midterm l Hearn and Baker –Chapter 4 ( ) –Chapter 10 ( ) –Chapter 11 (413 – 422) –Chapter 13 –Chapter 14 –Appendix ( ) l Red Book –Chapter 5 –Chapter 9 l Class Material –Antialiasing –Cube Maps –Visible Surface –Making Movies –Animation

Review – Vector Arithmatic l Add, subtract l Dot (to determine angle between and length of projection (when normalized vectors) –Do math to understand why normalization required l Cross product (Right-hand rule) –Did you know the length of the cross product of two vectors equals the area of the parallelogram formed by the two vectors? l Equations of lines l Distance from line to plane –Point of intersection

Review – Coordinate Space l Coordinate space –Right-handed coordinate system –openGL camera initialized to look down –z axis

Review - OpenGL l No significant coding required l I might ask you to tell me what a function does –One you’ve used for the projects l I might ask you to tell me what order to put the transformation commands l Direction of rotations l Ordering of polygon vertices l Back-face rendering l Textures –Filtering –Mipmap –Bump Map –Displacement Map –Alpha blending –Multi texturing

Review l Rendering Pipeline (model, light, view, clip, project)

Review l Homogeneous Coordinate System –What does w do? l Modeling Transformations –Rotate, translate, scale, rotate about arbitrary axis l Viewing Transformations –Orthographic (parallel) and Perspective l Understand how matrix formed by compositing many modeling and viewing transformations effects the vertices of a model and its rendering

Review l Color –Metamers –Relative changes versus absolute values –RGB sensitivity –Color spaces n Intuitive spaces, distance between similar colors l Lighting Equations –Dependent on what factors –Calculate the reflection vector –Know how parameters effect images

Review l Shading –Flat, Gouraud, Phong n Improvements versus cost –Indirect lighting n Ray tracing, radiosity u Viewer dependent/independent u Costs/benefits u Hemicube n Form Factors u Understand geometry of how they are computed u Understand simultaneous solution of all factors

Review - Antialiasing l Sampling and Quantization l Area Sampling (Weighted and unweighted) l What is a filter? l Super Sampling –Stochastic Supersampling l Nyquist Rate l How is this done in hardware?

Review – Textures l Filtering l Mip Map –Construction –Switching between layers –Advantages and disadvantages l Bump Map l Displacement Map l Alpha Blending l Repeating vs. Clamping

Review – Game Consoles l How can we really compare game consoles? –Triangles/Second versus 48 Pixel Quads / Sec –Texture Bandwidth –Antialiasing –MultiTexturing l How do these things influence system performance and how do they relate to the rendering pipeline?

Review - Visibility l Canonical View Volume –Advantages? –Used for Clipping l Back-face culling l Manifolds l Occlusion (Painter’s Algorithm) l Fragments (Analytic Visibility Algorithm) l BSP Tree –Multiple polygons aligned on same plane –Construction of tree / traversal of tree –Pros and cons l Warnock’s Algorithm l Z-buffer –What is its depth –Pros and cons

Review - Rotations l Euler Angles l Gimbal Lock l How many DOFs do we require l Math of axis angle –Why does axis angle use 4 DOFs to model 3 l Quaternion –Why better than Euler? –How is it similar to axis-angle –When is it better than axis-angle?

Review Splines l Know how to build M matrix –Hermite, bezier, b-spline l Understand each spline’s G matrix l Continuity terms l What’s a duck? l Uniform vs. non-uniform b-splines

Review – Environment Mapping l How is environment mapping done in hardware l Understand the basic problem we discussed in class that allows us to project an intersection with one face of cube to another face of cube

Review - Animation l Keyframing –Pros/cons l Inverse Kinematics –Know what it is l Motion Capture –Pros/cons

Review – Making Movies l What is compositing? l What is matchmoving? –How can we automate this? l What is a story board? l How can we preserve real-world lighting when compositing digital characters?