Adds create_new_stage and fixes merge error (#155)

This change applies a new `create_new_stage` setting in Isaac Sim's
SimulationApp to avoid creating a default new stage on startup, which
introduces additional performance overhead.
Also fixes an error in hydra code when rebasing.

- Bug fix (non-breaking change which fixes an issue)
- New feature (non-breaking change which adds functionality)

- [ ] I have run the [`pre-commit` checks](https://pre-commit.com/) 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

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---------
Signed-off-by: peterd-NV <peterd@nvidia.com>
Co-authored-by: peterd-NV <peterd@nvidia.com>
Co-authored-by: CY Chen <cyc@nvidia.com>
Co-authored-by: oahmednv <oahmed@Nvidia.com>
Co-authored-by: Toni-SM <aserranomuno@nvidia.com>

source/extensions/omni.isaac.lab/docs/CHANGELOG.rst

@@ -163,7 +163,7 @@ Added
 * Added full buffer property to :class:`omni.isaac.lab.utils.buffers.circular_buffer.CircularBuffer`
 
 
-0.27.30 (2024-12-15)
+0.27.31 (2024-12-15)
 ~~~~~~~~~~~~~~~~~~~~
 
 Added
@@ -172,7 +172,7 @@ Added
 * Added action clip to all :class:`omni.isaac.lab.envs.mdp.actions`.
 
 
-0.27.29 (2024-12-14)
+0.27.30 (2024-12-14)
 ~~~~~~~~~~~~~~~~~~~~
 
 Changed
@@ -181,7 +181,7 @@ Changed
 * Added check for error below threshold in state machines to ensure the state has been reached.
 
 
-0.27.28 (2024-12-13)
+0.27.29 (2024-12-13)
 ~~~~~~~~~~~~~~~~~~~~
 
 Fixed
@@ -190,7 +190,7 @@ Fixed
 * Fixed the shape of ``quat_w`` in the ``apply_actions`` method of :attr:`~omni.isaac.lab.env.mdp.NonHolonomicAction` (previously (N,B,4), now (N,4) since the number of root bodies B is required to be 1). Previously ``apply_actions`` errored because ``euler_xyz_from_quat`` requires inputs of shape (N,4).
 
 
-0.27.27 (2024-12-11)
+0.27.28 (2024-12-11)
 ~~~~~~~~~~~~~~~~~~~~
 
 Changed
@@ -201,7 +201,7 @@ Changed
 * Improved documentation to clarify the usage of the :meth:`~omni.isaac.lab.envs.mdp.rewards.base_height_l2` function in both flat and rough terrain settings.
 
 
-0.27.26 (2024-12-11)
+0.27.27 (2024-12-11)
 ~~~~~~~~~~~~~~~~~~~~
 
 Fixed
@@ -211,7 +211,7 @@ Fixed
   Jacobian computed w.r.t. to the root frame of the robot. This helps ensure that root pose does not affect the tracking.
 
 
-0.27.25 (2024-12-09)
+0.27.26 (2024-12-09)
 ~~~~~~~~~~~~~~~~~~~~
 
 Fixed
@@ -221,7 +221,7 @@ Fixed
   return only the states of the specified environment IDs.
 
 
-0.27.24 (2024-12-06)
+0.27.25 (2024-12-06)
 ~~~~~~~~~~~~~~~~~~~~
 
 Fixed
@@ -231,7 +231,7 @@ Fixed
   :attr:`~omni.isaac.lab.assets.Articulation.root_physx_view` level.
 
 
-0.27.23 (2024-12-06)
+0.27.24 (2024-12-06)
 ~~~~~~~~~~~~~~~~~~~~
 
 Changed
@@ -242,7 +242,7 @@ Changed
   disabled. Using an articulation root for rigid bodies is not needed and decreases overall performance.
 
 
-0.27.22 (2024-12-06)
+0.27.23 (2024-12-06)
 ~~~~~~~~~~~~~~~~~~~~
 
 Fixed
@@ -252,7 +252,7 @@ Fixed
   Earlier, the projection names used snakecase instead of camelcase.
 
 
-0.27.21 (2024-12-06)
+0.27.22 (2024-12-06)
 ~~~~~~~~~~~~~~~~~~~~
 
 Added
@@ -270,7 +270,7 @@ Changed
   :class:`~omni.isaac.lab.sensors.Camera` did not clip them and had a different behavior for both types.
 
 
-0.27.20 (2024-12-05)
+0.27.21 (2024-12-05)
 ~~~~~~~~~~~~~~~~~~~~
 
 Fixed
@@ -279,7 +279,7 @@ Fixed
 * Fixed the condition in ``isaaclab.sh`` that checks whether ``pre-commit`` is installed before attempting installation.
 
 
-0.27.19 (2024-12-04)
+0.27.20 (2024-12-04)
 ~~~~~~~~~~~~~~~~~~~~
 
 Fixed
@@ -288,7 +288,7 @@ Fixed
 * Fixed the order of the incoming parameters in :class:`omni.isaac.lab.envs.DirectMARLEnv` to correctly use ``NoiseModel`` in marl-envs.
 
 
-0.27.18 (2024-12-04)
+0.27.19 (2024-12-04)
 ~~~~~~~~~~~~~~~~~~~~
 
 Added
@@ -303,7 +303,7 @@ Added
 * Added ``replay_demos.py`` script to replay demos loaded from an HDF5 file.
 
 
-0.27.17 (2024-12-02)
+0.27.18 (2024-12-02)
 ~~~~~~~~~~~~~~~~~~~~
 
 Changed
@@ -312,6 +312,15 @@ Changed
 * Changed :class:`omni.isaac.lab.envs.DirectMARLEnv` to inherit from ``Gymnasium.Env`` due to requirement from Gymnasium v1.0.0 requiring all environments to be a subclass of ``Gymnasium.Env`` when using the ``make`` interface.
 
 
+0.27.17 (2024-11-20)
+~~~~~~~~~~~~~~~~~~~~
+
+Added
+^^^^^
+
+* Added ``create_new_stage`` setting in :class:`~omni.isaac.lab.app.AppLauncher` to avoid creating a default new stage on startup in Isaac Sim. This helps reduce the startup time when launching Isaac Lab.
+
+
 0.27.16 (2024-11-15)
 ~~~~~~~~~~~~~~~~~~~~
 
@@ -351,7 +360,7 @@ Added
   when importing them with :class:`~omni.isaac.lab.sim.converters.MeshConverter`.
 
 
-0.27.12 (2024-01-04)
+0.27.12 (2024-11-04)
 ~~~~~~~~~~~~~~~~~~~~
 
 Removed

source/extensions/omni.isaac.lab/omni/isaac/lab/app/app_launcher.py

@@ -493,6 +493,9 @@ class AppLauncher:
         if self._headless and not self._livestream:
             launcher_args["hide_ui"] = True
 
+        # avoid creating new stage at startup by default for performance reasons
+        launcher_args["create_new_stage"] = False
+
         # --simulation GPU device logic --
         self.device_id = 0
         device = launcher_args.get("device", AppLauncher._APPLAUNCHER_CFG_INFO["device"][1])