Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
8 Cards in this Set
- Front
- Back
|
What are the 5 platonic solids?
How many sides do they each have? What are 2 other basic solids? |
tetrahedron, cube, octahedron, dodecahedron, icosahedron
4, 6, 8, 12, 20 Sphere and Torus |
|
|
What are quadrics?
What are the 3 conics? |
Three dimensional extensions of conics
Elipses, parabolas, hyperbolas |
|
|
What is a halfedge data structure?
|
An edge centered DS for maintaining object information. For each face and each vertex one incident half-edge is stored.
|
|
|
How is the object file format (OFF) stored? Give an example for a unit cube.
|
OFF
numVertices numFaces numEdges //vertices x y z //faces num vertices v1 v2.. vn OFF 8 6 0 -0.500000 -0.500000 0.500000 0.500000 -0.500000 0.500000 -0.500000 0.500000 0.500000 0.500000 0.500000 0.500000 -0.500000 0.500000 -0.500000 0.500000 0.500000 -0.500000 -0.500000 -0.500000 -0.500000 0.500000 -0.500000 -0.500000 4 0 1 3 2 4 2 3 5 4 4 4 5 7 6 4 6 7 1 0 4 1 7 5 3 4 6 0 2 4 |
|
|
What are vertex arrays used for? What can be specified with a vertex array?
|
Speeding up rendering. The system will run through the whole array and render each vertex, color, or normal.
Position, color, and normal. |
|
|
What is the difference between global and local coordinate systems?
In what order is the global coordinate system read? In what order is the local coordinate system read? |
Thinking of the system in terms of the object or the scene. In global, we apply transformations to the object, and the scene remains stable. In local, we apply transformations to the scene, and the object remains stable.
Left to right Right to left |
|
|
What are glPushMatrix and glPopMatrix used for?
|
Saving the matrix stack and restoring the matrix stack. This allows us to apply transformations only locally and prevent global changes.
|
|
|
Why is 3d picking tricky?
What is one way to do 3d picking? |
The graphics pipeline needs to be reversed.
Draw the scene twice, give each pixel the object name and depth information. Rendering for select using a small picking region around the mouse. Get the selection, which is a list of objects rendered and their depth information. The one with the depth closest to the near plane of the frustum is picked. |
