Term
| How do you detect degenerate triangles? |
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Definition
you find 2 edges of the triangle and crossing the edges.
if the result of the norm of the vector is 0 it is degenerate |
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Term
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Definition
| It is splitting the world up in a way using partitions\splits using planes rather than splitting up the world by boxes or cubes, which allows us to cull pats of hte world and the objects in it which reduce the amount of information that needs to be processed at one time. |
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Term
| What is the Plane equation? |
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Definition
Ax + By + Cz - D = 0;
ABC is the normal of the plane
D is the distance to the plane/plane offset
XYZ is the point on the plane if the result is zero |
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Term
| What are the types of diving planes? |
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Definition
Arbitrary/General: No restrictions placed on how they are generated
Hint Planes: placed by the level designed in the map editing tool
Auto-partitioning/polygon aligned: planes are derived from the input geometry. Mose useful method for building a BSP tree, also used exclusively with indoor or enclosed environments |
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Term
| What are Node Based Trees? |
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Definition
Stores polygons/geometry in the nodes and leaves
Classic form of the BSP tree
Allows for quick rendering of the scene from back to front
Not a good choice for collision detection
Tree construction ends when no polygons to split by remain |
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Term
| What are leaf-based trees? |
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Definition
Stores polygons/geometry exclusively in the leaves
polygons in the leaves form "clusters"
Clusters form convex subsections of the world
good for collision detection
good for frustum culling
no control over draw order of individual faces
Splitting stops when
Leaf contains less than some minimum number of polys
a fixed tree depth has been reached
a good dividing plane cannot be found |
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Term
| What is the Sutherland-Hodgman Polygon-Clipping algorithm? |
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Definition
0: When both points lie in front of the plane, the end point is output
1: When the edge goes from in front of the plane to behind the plane, the intersection point is the output
2: When both points lie behind the plane, nothing is output
3: When the edge goes from behind the plane to in front of the plane, both intersection and the endpoint are output |
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