Intro
- Predicate notion of intersection- T/F
Area of a triangle
- A = 1/2 b * h
- Vector form: A = 1/2 || A x B || (half the magnitude of the cross product vector)
Cross product
- Direction of cross product
- RHCS: Up
- LHCS: Down
2D vector triangle
- Cross product must have 3 dimensions (Plug in 0 for Z if you want 2D)
Area of 2D triangle
Sign of area
Area-based predicates
- Left(a,b,c)
Boolean intersection
Proper vs improper intersection
- Can distinguish between proper and improper intersections with extensions to the intersection test