Moves meshes in the RayCaster to classvar to be shared between sensors

[pascal-roth]

Description

Moves meshes in the RayCaster to classvar to be shared between sensors. This should save memory.

Type of change

• Bug fix (non-breaking change which fixes an issue)

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

[Copilot]

Pull Request Overview

This PR moves the mesh storage for raycasting from instance attributes to class-level variables to allow sharing between sensors and reduce memory usage.

• Moves warp mesh and mesh view dictionaries to class-level with type annotations.
• Introduces an instance counter and a del method to clear the shared dictionaries when no instances remain.
• Updates the typing import to include ClassVar.

Comments suppressed due to low confidence (1)

source/isaaclab/isaaclab/sensors/ray_caster/ray_caster.py:314

• [nitpick] Relying on del for cleanup of shared class variables can be unpredictable due to Python's garbage collection behavior. Consider using an explicit cleanup method or context management to ensure reliable resource release.

def __del__(self):

[Mayankm96]

@pascal-roth Pre-commit is failing. Can you check?

[pascal-roth]

lets wait with a merge, just making some tests for the ray_caster to make sure that the new classvar is cleared correclty

[pascal-roth]

@Mayankm96 ready for a review, now the raycaster also has a first set of basic tests.

IMPORTANT: the test already run with pytest, commented out part at the top is for the time when everything is upgraded to pytest

[kellyguo11]

Looks like some tests are failing, is that expected?

[pascal-roth]

so regarding the tests:

• test_ray_caster.py: fail is expected as written in pytest (not sure why our unittest framework even catches that one)
• test_tiled_camera.py and test_contact_sensor.py fail but are not even in the log, don't think that is from this PR
• test_environment.py times out again

Lets really push for the pytest conversion, this will make the whole setup much easier

[kellyguo11]

Is the test_environment_determinism.py failure related to the changes?

[pascal-roth]

Not sure, will have to check today

[pascal-roth]

So, the tests are passing locally!

When investigating the log, then it complains about reaching a recusion depth during the raycasting.

source/isaaclab/isaaclab/utils/configclass.py:282: in _validate
    missing_fields.extend(_validate(value, prefix=current_path))
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

obj = '/isaac-sim/extscache/omni.warp.core-1.5.0+lx64/warp/bin/warp.so'
prefix = 'height_scanner.class_type.meshes./World/ground.device.runtime.device_map.cpu.runtime.device_map.cpu.runtime.device_ma...map.cpu.runtime.device_map.cpu.runtime.device_map.cpu.runtime.device_map.cpu.runtime.device_map.cpu.runtime.core._name'

    def _validate(obj: object, prefix: str = "") -> list[str]:
        """Check the validity of configclass object.
    
        This function checks if the object is a valid configclass object. A valid configclass object contains no MISSING
        entries.
    
        Args:
            obj: The object to check.
            prefix: The prefix to add to the missing fields. Defaults to ''.
    
        Returns:
            A list of missing fields.
    
        Raises:
            TypeError: When the object is not a valid configuration object.
        """
        missing_fields = []
    
        if type(obj) is type(MISSING):
            missing_fields.append(prefix)
            return missing_fields
>       elif isinstance(obj, (list, tuple)):
E       RecursionError: maximum recursion depth exceeded in __instancecheck__

I don't really know what might cause the issue as now every script is run on its own. Any idea @kellyguo11 or @Mayankm96 ?

[kellyguo11]

hmm very strange! I can't repro it locally either, even inside the docker container. but CI seems to be failing quite consistently on the Anymal-C rough environment, which also feels somehow related to the ray caster changes...

[pascal-roth]

I tend to agree, we can put some debug statements all over the code and see if we find something haha

[Mayankm96]

Shouldn't

self.meshes[mesh_prim_path] = wp_mesh

Be:

RayCaster.meshes[mesh_prim_path] = wp_mesh

I thought all write operations need to happen through class for classvar

[Mayankm96]

The ClassVar is only for static type-checking. It isn't enforced in any form by the interpreter.

[Mayankm96]

Would move the del after init to keep constructor and destructor near each other.