Removes dependency on XformPrim class for create_prim (#4307)

# Description

This MR removes the dependency on Isaac Sim XformPrim class for creating
prims. The class mainly handled setting the world or local poses, as
well as restting Xform operations. These are rather simple calls for
which we don't need to go through Isaac Sim. The MR adds a new
`transform` submodule that contains all the relevant functions as well
as their tests.

Fixes # (issue)

## Type of change

- New feature (non-breaking change which adds functionality)
- Breaking change (existing functionality will not work without user
modification)

## Checklist

- [x] I have read and understood the [contribution
guidelines](https://isaac-sim.github.io/IsaacLab/main/source/refs/contributing.html)
- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./isaaclab.sh --format`
- [x] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [x] 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
- [x] I have added my name to the `CONTRIBUTORS.md` or my name already
exists there

Author: Mayankm96

docs/source/api/lab/isaaclab.sim.utils.rst

@@ -10,6 +10,7 @@
     stage
     queries
     prims
+    transforms
     semantics
     legacy
 
@@ -34,6 +35,13 @@ Prims
   :members:
   :show-inheritance:
 
+Transforms
+----------
+
+.. automodule:: isaaclab.sim.utils.transforms
+  :members:
+  :show-inheritance:
+
 Semantics
 ---------
 

source/isaaclab/config/extension.toml

@@ -1,7 +1,7 @@
 [package]
 
 # Note: Semantic Versioning is used: https://semver.org/
-version = "0.51.1"
+version = "0.52.0"
 
 # Description
 title = "Isaac Lab framework for Robot Learning"

source/isaaclab/docs/CHANGELOG.rst

@@ -1,6 +1,23 @@
 Changelog
 ---------
 
+0.52.0 (2026-01-02)
+~~~~~~~~~~~~~~~~~~~
+
+Added
+^^^^^
+
+* Added :mod:`~isaaclab.sim.utils.transforms` module to handle USD Xform operations.
+* Added passing of ``stage`` to the :func:`~isaaclab.sim.utils.prims.create_prim` function
+  inside spawning functions to allow for the creation of prims in a specific stage.
+
+Changed
+^^^^^^^
+
+* Changed :func:`~isaaclab.sim.utils.prims.create_prim` function to use the :mod:`~isaaclab.sim.utils.transforms`
+  module for USD Xform operations. It removes the usage of Isaac Sim's XformPrim class.
+
+
 0.51.2 (2025-12-30)
 ~~~~~~~~~~~~~~~~~~~
 

source/isaaclab/isaaclab/sim/spawners/from_files/from_files.py

@@ -198,7 +198,7 @@ def spawn_ground_plane(
 
     # Spawn Ground-plane
     if not stage.GetPrimAtPath(prim_path).IsValid():
-        create_prim(prim_path, usd_path=cfg.usd_path, translation=translation, orientation=orientation)
+        create_prim(prim_path, usd_path=cfg.usd_path, translation=translation, orientation=orientation, stage=stage)
     else:
         raise ValueError(f"A prim already exists at path: '{prim_path}'.")
 
@@ -327,6 +327,7 @@ def _spawn_from_usd_file(
             translation=translation,
             orientation=orientation,
             scale=cfg.scale,
+            stage=stage,
         )
     else:
         logger.warning(f"A prim already exists at prim path: '{prim_path}'.")

source/isaaclab/isaaclab/sim/spawners/lights/lights.py

@@ -50,7 +50,9 @@ def spawn_light(
     if stage.GetPrimAtPath(prim_path).IsValid():
         raise ValueError(f"A prim already exists at path: '{prim_path}'.")
     # create the prim
-    prim = create_prim(prim_path, prim_type=cfg.prim_type, translation=translation, orientation=orientation)
+    prim = create_prim(
+        prim_path, prim_type=cfg.prim_type, translation=translation, orientation=orientation, stage=stage
+    )
 
     # convert to dict
     cfg = cfg.to_dict()

source/isaaclab/isaaclab/sim/spawners/shapes/shapes.py

@@ -282,7 +282,7 @@ def _spawn_geom_from_prim_type(
 
     # spawn geometry if it doesn't exist.
     if not stage.GetPrimAtPath(prim_path).IsValid():
-        create_prim(prim_path, prim_type="Xform", translation=translation, orientation=orientation)
+        create_prim(prim_path, prim_type="Xform", translation=translation, orientation=orientation, stage=stage)
     else:
         raise ValueError(f"A prim already exists at path: '{prim_path}'.")
 
@@ -291,7 +291,7 @@ def _spawn_geom_from_prim_type(
     mesh_prim_path = geom_prim_path + "/mesh"
 
     # create the geometry prim
-    create_prim(mesh_prim_path, prim_type, scale=scale, attributes=attributes)
+    create_prim(mesh_prim_path, prim_type, scale=scale, attributes=attributes, stage=stage)
     # apply collision properties
     if cfg.collision_props is not None:
         schemas.define_collision_properties(mesh_prim_path, cfg.collision_props)

source/isaaclab/isaaclab/sim/spawners/wrappers/wrappers.py

@@ -67,7 +67,7 @@ def spawn_multi_asset(
 
     # find a free prim path to hold all the template prims
     template_prim_path = sim_utils.get_next_free_prim_path("/World/Template", stage=stage)
-    sim_utils.create_prim(template_prim_path, "Scope")
+    sim_utils.create_prim(template_prim_path, "Scope", stage=stage)
 
     # spawn everything first in a "Dataset" prim
     proto_prim_paths = list()
@@ -116,7 +116,7 @@ def spawn_multi_asset(
             Sdf.CopySpec(env_spec.layer, Sdf.Path(proto_path), env_spec.layer, Sdf.Path(prim_path))
 
     # delete the dataset prim after spawning
-    sim_utils.delete_prim(template_prim_path)
+    sim_utils.delete_prim(template_prim_path, stage=stage)
 
     # set carb setting to indicate Isaac Lab's environments that different prims have been spawned
     # at varying prim paths. In this case, PhysX parser shouldn't optimize the stage parsing.

source/isaaclab/isaaclab/sim/utils/__init__.py

@@ -10,3 +10,4 @@
 from .queries import *  # noqa: F401, F403
 from .semantics import *  # noqa: F401, F403
 from .stage import *  # noqa: F401, F403
+from .transforms import *  # noqa: F401, F403