Guidelines for serializing btGImpactConvexDecompositionShape

[sylvain.meunier]

Hello,

I use GImpact stuffs for handling collision between a lot of moving meshes (no dynamics but an extensive use of contactTest).

Testing Bullet, I have found btGImpactConvexDecompositionShape provides a huge performance boost over btGImpactMeshShape but building it is relatively slow. I think preprocessing then serializing the shapes can reduce the overall loading time.

However there is no serialization available for btGImpactConvexDecompositionShape (Am I wrong?).

Is there any guidelines for implementing serialization ?

Thanks

[Erwin Coumans]

Modifying the serialization is not very easy.

In a nutshell, you have to switch on the serialization projects in CMake, and then
compile the project in 32bit mode, then copy the Bullet/src/LinearMath/btSerializer.cpp content, then compile again using 64bit mode, and merge the 32bit DNA strings in btSerializer.cpp

We will add support to serialize btGImpactConvexDecompositionShape soon,
Thanks,
Erwin

[sylvain.meunier]

Thank you for pointing out the compilation trick about sBulletDNAstr64 and sBulletDNAstr. This isn't mentioned in the wiki.

In relation to your last statement, are you also implementing btGImpactConvexDecompositionShape serialization ?

[sylvain.meunier]

After jumping from a project to another... Here is the serialization patch.

This patch includes :
- updates for building on VS2005;
- updates for building bullet with premake;
- updates for serializing btGImpactCompoundShape;
- updates for debugging btGImpactCompoundShape.

I used the revision 2660 of Bullet with a local GIT repository.

If someone can review and comment this patch and maybe improve it, this would be nice.

[Erwin Coumans]

Thanks for the effort of sharing the patch. I tried applying it to latest trunk, but there are a lot of conflicts.

It would be great if you can create some new patches, based on latest trunk, with only one feature/fix per patch, not a combined patch.

Thanks again,
Erwin