Hello, I am trying to import a mesh into Isaac Gym. The mesh is already convex. I do not want Isaac Gym to change the mesh, but just import it as-is. Later this mesh will consist of multiple convex submeshes (from VHACD). I want to do my own convex decomposition so that I can use this mesh outside of Isaac Gym as well.
The problem is that once imported, the mesh does change. The GIF shows me toggling between the visual mesh visualisation and the collision mesh visualisation. You can see that although they use the same .obj file, Isaac Gym does change the collision mesh during importing – e.g. see the vertex moving in the lower-left corner of the object.
I am using these options:
asset_options.convex_decomposition_from_submeshes = True
asset_options.vhacd_enabled = False
Question: how can I stop Isaac Gym from changing the collision mesh during importing? Why is it doing this, when the mesh is already convex? Is it somehow trying to compute a convex decomposition of the mesh anyway? Thank you!
This is a minimal example of importing one convex hull, but what I really want is a whole cube mesh to be imported unchanged (consisting of convex submeshes). Currently the collision mesh does get imported but it is missing some vertices / triangles.
I am using the latest Isaac Gym (Preview 4). I understand that it is now deprecated in favour of Isaac Lab, but it does exactly what I need it do to (other than this small import issue), so I would really appreciate your help with this.
Many thanks for your help!
The mesh .obj is below:
mesh_collision.obj
o convex_7
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