Simulation Visualization¶

ke.visual.sim synchronizes KangSimWorld objects to renderer and scene visuals.

Type	Role
`SimWorldVisualizer`	Registers simulation objects and synchronizes their visual state
`VisualBatch`	CPU/GPU external-buffer visual returned by `add()`
`VisualArticulationSceneGraph`	Inspectable per-link articulation record returned by `add_scene_graph()`
`VisualRigidSceneGraph`	Inspectable rigid-body record returned by `add_scene_graph()`
`VisualBodyPick`	Maps a renderer selection to environment, object, and body IDs

Batched rendering¶

Use add() for normal simulation rendering, including batched environments:

self.visual: ke.visual.sim.SimWorldVisualizer = (
    ke.visual.sim.SimWorldVisualizer(app=self, world=self.world)
)
self.robot_visual: ke.visual.sim.VisualBatch = self.visual.add(
    sim_handle=robot,
    mjcf_path=mjcf_path,
    path="/robot",
    material=material,
)

def fixed_update(self, fixed_dt):
    self.world.advance(duration=fixed_dt)

def pre_render(self):
    self.visual.sync()

add() returns a VisualBatch, not an ArticulationVisual. It is the normal rendering handle for both rigid bodies and articulations and uses an ExternalBuffer-backed path.

Simulation state and scene/render state are separate. Advance physics in fixed_update() and synchronize visuals in pre_render() so rendering speed does not alter the physics rate.

Inspectable SceneGraph visuals¶

Use add_scene_graph() when individual prims must be visible and selectable in the editor:

record: ke.visual.sim.VisualArticulationSceneGraph = self.visual.add_scene_graph(
    sim_handle=robot,
    mjcf_path=mjcf_path,
    env_id=0,
)
record.set_color(color=(0.8, 0.8, 0.9, 1.0))
record.set_collision_visible(visible=True)

For an articulation, record is a VisualArticulationSceneGraph and record.articulation_visual is the underlying ArticulationVisual synchronized from the simulation. Most applications should use the record rather than call the underlying bridge directly.

VisualBatch.release() removes one batch. SimWorldVisualizer.release() releases every visual registered through that visualizer.

Use one representation deliberately:

add() / VisualBatch for throughput and batched environments.
add_scene_graph() for inspectable prims, selection, and collision display.

Examples:

python/examples/sim_world_minimal.py
python/examples/sim_world_multi_env.py
python/examples/mjcf_dof_control.py