Optimizes getters of data inside asset classes

[Mayankm96]

Description

Previously the root positions was obtained by performing the following steps:

1. Call PhysX getters to get transforms and velocities
2. Concatenating the two to make a single state tensor
3. Indexing this tensor to get the position

For applications where we only want the positions, the above is an expensive operation as we call CUDA-MemCpy twice and then do concatenation which adds overhead.

This MR simplifies the above process by having separate lazy buffers for poses, velocities and states.

Fixes # (issue)

Type of change

• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Screenshots

Please attach before and after screenshots of the change if applicable.

Checklist

• I have run the pre-commit checks with ./isaaclab.sh --format
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• I have updated the changelog and the corresponding version in the extension's config/extension.toml file
• I have added my name to the CONTRIBUTORS.md or my name already exists there

[jtigue-bdai]

I think its a good separation for the pose vs velocity buffers. The added lazy buffer layer in the update call is also a nice addition. Tests all pass (at least the ones I think are dependant) so I think its in good shape. Can you add the performance graphs to the PR description for reference when we look back?

[Mayankm96]

Will share my logs here tomorrow. It's on a different PC. Might have made sense to run OSMO benchmarking but that seems like quite a bit of an effort.

[Mayankm96]

@kellyguo11 @matthewtrepte could we run the perf benchmark on this? If it works then this should be merged. It cleans up stuff.

[kellyguo11]

@kellyguo11 @matthewtrepte could we run the perf benchmark on this? If it works then this should be merged. It cleans up stuff.

Could you rebase the changes? Some of the regression tests should run automatically now as part of the CI, but we’ll need to update the branch to pick up the change for the tests.