[ODE] RE: Terrain<->Box collision without tri-collider
McEvoy, Nick
nick.mcevoy at dsto.defence.gov.au
Tue Jan 28 17:19:02 2003
Fabian Herb wrote:
>It's probably a good idea to have (multiple) early-exit tests. My own
>code creates almost ready-to-use contact normals and penetration
>depths for every triangle it checks, although all, except perhaps one
>or two, don't collide at all.
Yep.
>But checking every triangle in this manner has some negative aspects:
>- All the collision normals point away direction from the triangle,
>even if you have edge-edge contacts or a box face colliding with a
>terrain vertex.
Yes, this is a good point.
>- I don't know how fast this tri-box collider really is (I didn't
>check out the docs yet), but checking every triangle for its own
>means checking each terrain edge twice and each vertex between 4 and
>8 times (depending on if you use alternating triangle direction in
>the mesh).
Sorry I haven't done any performance testing myself ... but the docs on Fast 3D Triangle-Box Overlap Testing do.
I should have pointed out that my code is *not* currently written for speed ... performance is not an issue for me at the moment ... I just like to get something working first then tune it later. At the moment I'm writing a game with a JetSki jumping over realtime waves running at a reasonable frame rate ... things might change as I add more JetSki racers though. :(
>Anyway, thanks for your contribution :-)
No worries.
Nick