PhysicsCollisionAPI

Makes a Gprim a collision shape. Enumerated by usd-schemas CONTAINS PhysicsCollisionAPI. The shape geometry comes from the prim_type component (Cube, Capsule, Mesh, …); this API only switches collision on and binds the shape to a scene.

• Applies to: Gprim

• Read only when listed in usd-schemas.

• Uses blocks: prim

What USD population writes

Applying this API is what makes the producer publish the prim’s geometry attributes (see each Gprim component) and resolve its physics material binding. Its own two properties are published as resolved value and authored relationship respectively.

Columns

Raw fallback is the USD schema value. Producer writes is what ovstage population puts in the column for a USD stage. Parser default applies on the consumer when the column is absent, in stage units. diverges means writing the raw fallback literally parses differently from omitting the column (the parser default): USD population may well publish that very value for an unauthored attribute, so the marker is about the column being present, not about its value.

Column	Type	Units	Raw fallback	Producer writes	Parser default	If absent
physics:collisionEnabled	bool8	none	true	resolved USD value (authored, else raw fallback)	true	Shape collides.
physics:simulationOwner	uint64 array, RELATIONSHIP_PATH_ID			not written		Shape follows its body’s scene, or the default scene when standalone.

Interactions

• prim: The decomposed world scale of this prim is baked into the shape geometry (see each prim_type’s derived values). A shape under a rigid body gets its local pose from this prim’s transform relative to the body prim.

• MaterialBindingAPI: Without a material binding the shape has no material slot and uses the scene default material.

• PhysicsRigidBodyAPI: A collider with no rigid body ancestor or self is a static shape.