GIMPACT vs Convex Collision performance problem.

[DevO]

I am using now GIMPACTBullet connection.
GIMPACT vs GIMPACT is really fast.
But I and have noticed that collision of GIMPACT with simple Bullet convex shape like Box can be really slow.

If btIDebugDraw::DBG_DrawWireframe is enabled the whole GIMPACT mesh will be yellow indicates that all triangles will be tested vs box.

Do some one have ideas how to fix this?

[DevO]

Nobody, any idea???

[projectileman]

Yes, that happens in the earlier version of GIMPACT with Bullet integration. It is caused by a mistake of the Collision Dispatcher which doesn't handle well compound shapes vs GIMPACT trimeshes: actually it tests all triangles vs each sub shape.


I've fixed these issues in the new version of GIMPACT, which will be released soon in July. This version could be considered an improvement to the Bullet engine, and some of the new features are:

- Works more closely with Bullet. It uses Bullet types and uses some bullet collision algorithms.

- C++ object oriented.

- Generic Bounding box Tree structure for colliding large sets of shapes (Compounds and Trimeshes) ; works similar to the btOptimizedBvh, but it has the capability of collide two Tree sets. Also supports Primitive Vs Node Collision for improving performance.

- Trimeshes work closely with the btStridingMeshInterface objects. Data won't be duplicated anymore, and many Bodies can share the same trimesh.


Well, I hope release this library soon. Any ideas?
Thanks,
Att: Francisco León

[DevO]

Thanks, all this sound very well!!!

I hope too this will be release soon!!!

Until some small problems this is (was) the most problem in my Bullet integration.

[chrislu]

hi,
is the GIMPACT 0.2 release the one with these improvements?

[Erwin Coumans]

It looks like it, and I just merged the contribution into Bullet Subversion, so it will be available from Bullet 2.54 too.

Thanks,
Erwin