Re: [Algorithms] Kinematic Collision

[David B. <db...@fa...>]

>>>
Figuring out what surface is fine to "be on" and how to handle
surfaces you should not be in, or the penetration into either is
a major pain.  In the simple cases its trivial, but in the face
of arbitrary geometry from the artists, the slightest things can
creep in to mess up algorithms that use to work fine.  What
amazes me is that this is one of those problems where the
solution is more or less obvious to a human, but is difficult to
express in realtime code.
<<<

While perhaps not relevant to big games, my opinion is that the best way
to tackle this is 2 pronged. Firstly handle all casses as well as
possible, dont assume that the player is ever in a valid location and
handle interpenetration as gracefully as possible. 

Secondly "prevent" the artists from creating unpleasant geometry as far
as possible by defining collision geometry editing operations in such a
way as to make it tricky to create invalid objects. ie just allow CSG
with convexes(yeah CSG has pitfalls but problems can be detected during
editing) + primitives like capsules/spheres/boxes. General triangle mesh
collision geometry, created by artists rather than code, just seems like
something which speeds up initial creation but then has a large cost
later on trying to solve all the problems which appear during play.

David

-- 
http://www.fastmail.fm - One of many happy users:
  http://www.fastmail.fm/docs/quotes.html