Refactor: replace step(render=) param with render_enabled property

Replace the render flag parameter on step() with a mutable render_enabled
property on all env base classes. Preserves the gymnasium.Env.step() API.

Usage:
    env.render_enabled = False
    env.step(action)

Classes: ManagerBasedEnv, ManagerBasedRLEnv, DirectRLEnv, DirectMARLEnv,
MARL utility wrappers.

Author: Kelly Guo

source/isaaclab/docs/CHANGELOG.rst

@@ -7,11 +7,12 @@ Changelog
 Added
 ^^^^^
 
-* Added ``render`` flag to the ``step()`` method of all environment base classes
+* Added ``render_enabled`` property to all environment base classes
   (:class:`~isaaclab.envs.ManagerBasedEnv`, :class:`~isaaclab.envs.ManagerBasedRLEnv`,
   :class:`~isaaclab.envs.DirectRLEnv`, :class:`~isaaclab.envs.DirectMARLEnv`).
-  Passing ``render=False`` skips all rendering calls (GUI updates, RTX sensor rendering,
-  post-reset re-renders) while physics simulation continues normally.  Defaults to ``True``
+  Setting ``env.render_enabled = False`` before calling ``step()`` skips all rendering calls
+  (GUI updates, RTX sensor rendering, post-reset re-renders) while physics simulation continues
+  normally.  The property can be toggled between steps for per-step control.  Defaults to ``True``
   for full backward compatibility.
 
 

source/isaaclab/isaaclab/envs/direct_marl_env.py

@@ -217,6 +217,14 @@ def _init_sim(self, render_mode: str | None = None, **kwargs):
         # initialize data and constants
         # -- counter for simulation steps
         self._sim_step_counter = 0
+        # -- rendering control
+        self.render_enabled: bool = True
+        """Whether rendering is enabled during :meth:`step`.
+
+        When set to ``False``, all rendering calls (GUI updates, RTX sensor rendering, post-reset
+        re-renders) are skipped while physics simulation continues normally.  This can be toggled
+        between steps to control rendering on a per-step basis.  Defaults to ``True``.
+        """
         # -- counter for curriculum
         self.common_step_counter = 0
         # -- init buffers
@@ -373,7 +381,7 @@ def reset(
         # return observations
         return self.obs_dict, self.extras
 
-    def step(self, actions: dict[AgentID, ActionType], render: bool = True) -> EnvStepReturn:
+    def step(self, actions: dict[AgentID, ActionType]) -> EnvStepReturn:
         """Execute one time-step of the environment's dynamics.
 
         The environment steps forward at a fixed time-step, while the physics simulation is decimated at a
@@ -391,11 +399,11 @@ def step(self, actions: dict[AgentID, ActionType], render: bool = True) -> EnvSt
         5. Apply interval events if they are enabled.
         6. Compute observations.
 
+        Rendering can be controlled per-step via :attr:`render_enabled`.
+
         Args:
             actions: The actions to apply on the environment (keyed by the agent ID).
                 Shape of individual tensors is (num_envs, action_dim).
-            render: Whether to render during this step. When False, all rendering calls
-                (GUI updates, RTX sensor rendering) are skipped. Defaults to True.
 
         Returns:
             A tuple containing the observations, rewards, resets (terminated and truncated) and
@@ -413,7 +421,7 @@ def step(self, actions: dict[AgentID, ActionType], render: bool = True) -> EnvSt
 
         # check if we need to do rendering within the physics loop
         # note: uses cached property to avoid settings lookup every step
-        is_rendering = render and self.sim.is_rendering
+        is_rendering = self.render_enabled and self.sim.is_rendering
 
         # perform physics stepping
         for _ in range(self.cfg.decimation):

source/isaaclab/isaaclab/envs/direct_rl_env.py

@@ -223,6 +223,14 @@ def _init_sim(self, render_mode: str | None = None, **kwargs):
         # initialize data and constants
         # -- counter for simulation steps
         self._sim_step_counter = 0
+        # -- rendering control
+        self.render_enabled: bool = True
+        """Whether rendering is enabled during :meth:`step`.
+
+        When set to ``False``, all rendering calls (GUI updates, RTX sensor rendering, post-reset
+        re-renders) are skipped while physics simulation continues normally.  This can be toggled
+        between steps to control rendering on a per-step basis.  Defaults to ``True``.
+        """
         # -- counter for curriculum
         self.common_step_counter = 0
         # -- init buffers
@@ -367,7 +375,7 @@ def reset(self, seed: int | None = None, options: dict[str, Any] | None = None)
         # return observations
         return self._get_observations(), self.extras
 
-    def step(self, action: torch.Tensor, render: bool = True) -> VecEnvStepReturn:
+    def step(self, action: torch.Tensor) -> VecEnvStepReturn:
         """Execute one time-step of the environment's dynamics.
 
         The environment steps forward at a fixed time-step, while the physics simulation is decimated at a
@@ -385,10 +393,10 @@ def step(self, action: torch.Tensor, render: bool = True) -> VecEnvStepReturn:
         5. Apply interval events if they are enabled.
         6. Compute observations.
 
+        Rendering can be controlled per-step via :attr:`render_enabled`.
+
         Args:
             action: The actions to apply on the environment. Shape is (num_envs, action_dim).
-            render: Whether to render during this step. When False, all rendering calls
-                (GUI updates, RTX sensor rendering) are skipped. Defaults to True.
 
         Returns:
             A tuple containing the observations, rewards, resets (terminated and truncated) and extras.
@@ -403,7 +411,7 @@ def step(self, action: torch.Tensor, render: bool = True) -> VecEnvStepReturn:
 
         # check if we need to do rendering within the physics loop
         # note: uses cached property to avoid settings lookup every step
-        is_rendering = render and self.sim.is_rendering
+        is_rendering = self.render_enabled and self.sim.is_rendering
 
         # perform physics stepping
         for _ in range(self.cfg.decimation):

source/isaaclab/isaaclab/envs/manager_based_env.py

@@ -153,6 +153,15 @@ def _init_sim(self):
         # counter for simulation steps
         self._sim_step_counter = 0
 
+        # rendering control
+        self.render_enabled: bool = True
+        """Whether rendering is enabled during :meth:`step`.
+
+        When set to ``False``, all rendering calls (GUI updates, RTX sensor rendering, post-reset
+        re-renders) are skipped while physics simulation continues normally.  This can be toggled
+        between steps to control rendering on a per-step basis.  Defaults to ``True``.
+        """
+
         # allocate dictionary to store metrics
         self.extras = {}
 
@@ -485,7 +494,7 @@ def reset_to(
         # return observations
         return self.obs_buf, self.extras
 
-    def step(self, action: torch.Tensor, render: bool = True) -> tuple[VecEnvObs, dict]:
+    def step(self, action: torch.Tensor) -> tuple[VecEnvObs, dict]:
         """Execute one time-step of the environment's dynamics.
 
         The environment steps forward at a fixed time-step, while the physics simulation is
@@ -494,10 +503,10 @@ def step(self, action: torch.Tensor, render: bool = True) -> tuple[VecEnvObs, di
         simulation steps per environment step) and the :attr:`ManagerBasedEnvCfg.sim.dt` (physics time-step).
         Based on these parameters, the environment time-step is computed as the product of the two.
 
+        Rendering can be controlled per-step via :attr:`render_enabled`.
+
         Args:
             action: The actions to apply on the environment. Shape is (num_envs, action_dim).
-            render: Whether to render during this step. When False, all rendering calls
-                (GUI updates, RTX sensor rendering) are skipped. Defaults to True.
 
         Returns:
             A tuple containing the observations and extras.
@@ -509,7 +518,7 @@ def step(self, action: torch.Tensor, render: bool = True) -> tuple[VecEnvObs, di
 
         # check if we need to do rendering within the physics loop
         # note: uses cached property to avoid settings lookup every step
-        is_rendering = render and self.sim.is_rendering
+        is_rendering = self.render_enabled and self.sim.is_rendering
 
         # perform physics stepping
         for _ in range(self.cfg.decimation):

source/isaaclab/isaaclab/envs/manager_based_rl_env.py

@@ -158,7 +158,7 @@ def setup_manager_visualizers(self):
     Operations - MDP
     """
 
-    def step(self, action: torch.Tensor, render: bool = True) -> VecEnvStepReturn:
+    def step(self, action: torch.Tensor) -> VecEnvStepReturn:
         """Execute one time-step of the environment's dynamics and reset terminated environments.
 
         Unlike the :class:`ManagerBasedEnv.step` class, the function performs the following operations:
@@ -171,10 +171,10 @@ def step(self, action: torch.Tensor, render: bool = True) -> VecEnvStepReturn:
         6. Compute the observations.
         7. Return the observations, rewards, resets and extras.
 
+        Rendering can be controlled per-step via :attr:`render_enabled`.
+
         Args:
             action: The actions to apply on the environment. Shape is (num_envs, action_dim).
-            render: Whether to render during this step. When False, all rendering calls
-                (GUI updates, RTX sensor rendering) are skipped. Defaults to True.
 
         Returns:
             A tuple containing the observations, rewards, resets (terminated and truncated) and extras.
@@ -186,7 +186,7 @@ def step(self, action: torch.Tensor, render: bool = True) -> VecEnvStepReturn:
 
         # check if we need to do rendering within the physics loop
         # note: uses cached property to avoid settings lookup every step
-        is_rendering = render and self.sim.is_rendering
+        is_rendering = self.render_enabled and self.sim.is_rendering
 
         # perform physics stepping
         for _ in range(self.cfg.decimation):

source/isaaclab/isaaclab/envs/utils/marl.py

@@ -97,7 +97,7 @@ def reset(self, seed: int | None = None, options: dict[str, Any] | None = None)
 
             return obs, extras
 
-        def step(self, action: torch.Tensor, render: bool = True) -> VecEnvStepReturn:
+        def step(self, action: torch.Tensor) -> VecEnvStepReturn:
             # split single-agent actions to build the multi-agent ones
             # FIXME: This implementation assumes the spaces are fundamental ones. Fix it to support composite spaces
             index = 0
@@ -108,7 +108,7 @@ def step(self, action: torch.Tensor, render: bool = True) -> VecEnvStepReturn:
                 index += delta
 
             # step the environment
-            obs, rewards, terminated, time_outs, extras = self.env.step(_actions, render=render)
+            obs, rewards, terminated, time_outs, extras = self.env.step(_actions)
 
             # use environment state as observation
             if self._state_as_observation:
@@ -233,7 +233,7 @@ def reset(
 
             return obs, extras
 
-        def step(self, actions: dict[AgentID, ActionType], render: bool = True) -> EnvStepReturn:
+        def step(self, actions: dict[AgentID, ActionType]) -> EnvStepReturn:
             # split agent actions to build the multi-agent ones
             # FIXME: This implementation assumes the spaces are fundamental ones. Fix it to support composite spaces
             index = 0
@@ -244,7 +244,7 @@ def step(self, actions: dict[AgentID, ActionType], render: bool = True) -> EnvSt
                 index += delta
 
             # step the environment
-            obs, rewards, terminated, time_outs, extras = self.env.step(_actions, render=render)
+            obs, rewards, terminated, time_outs, extras = self.env.step(_actions)
 
             # use environment state as observation
             if self._state_as_observation:

source/isaaclab/test/envs/test_env_rendering_logic.py

@@ -243,7 +243,7 @@ def wrapped_step(dt):
 
 @pytest.mark.parametrize("env_type", ["manager_based_env", "manager_based_rl_env", "direct_rl_env"])
 def test_env_render_false_skips_rendering(env_type, physics_callback, render_callback):
-    """Test that passing render=False to step() skips all rendering while physics continues."""
+    """Test that setting render_enabled=False skips all rendering while physics continues."""
     physics_cb, get_physics_stats = physics_callback
     render_cb, get_render_stats = render_callback
 
@@ -295,17 +295,18 @@ def wrapped_step(dt):
         # create a zero action tensor for stepping the environment
         actions = torch.zeros((env.num_envs, 0), device=env.device)
 
-        # Step with render=False for several steps
+        # Step with render_enabled=False for several steps
+        env.render_enabled = False
         for i in range(10):
-            env.step(action=actions, render=False)
+            env.step(action=actions)
 
             # Physics should still advance normally
             _, num_physics_steps = get_physics_stats()
-            assert num_physics_steps == (i + 1) * env.cfg.decimation, "Physics steps mismatch with render=False"
+            assert num_physics_steps == (i + 1) * env.cfg.decimation, "Physics steps mismatch with render_enabled=False"
 
             # No rendering should have occurred
             _, num_render_steps = get_render_stats()
-            assert num_render_steps == 0, f"Expected 0 render steps with render=False, got {num_render_steps}"
+            assert num_render_steps == 0, f"Expected 0 render steps with render_enabled=False, got {num_render_steps}"
 
     finally:
         if viz is not None and original_step is not None:
@@ -320,7 +321,7 @@ def wrapped_step(dt):
 
 @pytest.mark.parametrize("env_type", ["manager_based_env", "manager_based_rl_env", "direct_rl_env"])
 def test_env_render_flag_mixed_steps(env_type, physics_callback, render_callback):
-    """Test that render flag can be toggled between steps and rendering counts are correct."""
+    """Test that render_enabled can be toggled between steps and rendering counts are correct."""
     physics_cb, get_physics_stats = physics_callback
     render_cb, get_render_stats = render_callback
 
@@ -374,10 +375,11 @@ def wrapped_step(dt):
 
         expected_render_steps = 0
 
-        # Step 5 times with render=True, then 5 with render=False
+        # Step 5 times with render_enabled=True, then 5 with render_enabled=False
         for i in range(10):
             should_render = i < 5
-            env.step(action=actions, render=should_render)
+            env.render_enabled = should_render
+            env.step(action=actions)
 
             # Physics always advances
             _, num_physics_steps = get_physics_stats()