GDC 2014 Erin Catto 내용 정리

https://www.youtube.com/watch?v=SHinxAhv1ZE

Physics for Game Programmers : Understanding Constraints

Impulse
- linear Impulse : ƛn
- Angular Impulse : ƛ(r x n)

Contact Solver
- Glober Solver : Slow, Large Memory
- Local Solver : Solutions for global solver

Local Solver
- Convergence Problems(수렴 문제) : 즉, 원하는 impulse를 계산하기 위해서, worse case일 수록 더 많은 iterations을 요구하는게 나타남
- Solution for Convergence Problems : Warm Starting
- Overshooting for Warm Starting : Warm Starting으로 인해, 오브젝트에 가해질 impulse가 더 가해지는 문제인 Overshoot가 나타남
- Solution for Overshoot : Block Solvers (Handle contacts simultaneously)

Position Correction
- Don't use Acceleration Constraint
- Use Velocity Constraint
- Use only position constraint such as cloth constraint, character solver
- Use plane solver specific for the character solver