PhysxSphereFillCollisionAPI

Sphere fill cooking parameters for a Mesh collider with physics:approximation sphereFill. Cooking inputs only; nothing here is verified. voxelResolution’s schema fallback differs from the consumer’s absent-column seed.

• Applies to: Gprim

• Requires on the same prim: PhysicsCollisionAPI

• Read only when listed in usd-schemas.

What USD population writes

Every declared attribute of an applied collision API is published at its resolved value; all four columns land as their raw fallbacks when unauthored. No derivation.

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
physxSphereFillCollision:maxSpheres	int32	none	128	resolved USD value (authored, else raw fallback)	128	128 (defaultMaxSpheres) from the SphereFillCookingParams constructor.
physxSphereFillCollision:seedCount	int32	none	1000	resolved USD value (authored, else raw fallback)	1000	1000 (defaultSeedCount).
physxSphereFillCollision:voxelResolution	int32	none	50000	resolved USD value (authored, else raw fallback)	100000 diverges	100000 (defaultCookedVoxelResolution). The USD schema fallback is 50000 and the producer publishes it, so a hand-populated stage that omits the column voxelises twice as finely as USD population.
physxSphereFillCollision:fillMode	uint64, TOKEN_ID	none	flood	resolved USD value (authored, else raw fallback)	flood	flood (SphereFillMode::eFLOOD). Accepted tokens flood, raycast, surface; an absent column or any other token keeps the current value.

Interactions

• PhysicsMeshCollisionAPI: Read by parseSphereFillCookingExt only for descriptor kind sphereFill (SpherePointsPhysxShapeDesc). No usd-schemas gate: the columns are read whenever they exist on the collider.

Known divergences

• note (consumer) physxSphereFillCollision:voxelResolution: Absent column seeds 100000 (PhysxCookingParams.h defaultCookedVoxelResolution, shared with convex decomposition) while the USD schema fallback published by the producer is 50000. Only a hand-populated stage that omits the column is affected. Cooking input, not a PhysX default.

Notes

• Cooking APIs on a Mesh cannot be verified by the generated tests: the parameters only change the set of PxSphereGeometry shapes the cooking service emits, PhysX exposes no getter for them, and the builder writes no mesh arrays.