Sphere#

Sphere geometry. With PhysicsCollisionAPI applied it becomes a PhysX sphere shape whose radius is |radius| times the largest component of the prim’s world scale.

What USD population writes#

Geometry attributes of a Gprim are published only from the curated list (size, radius, height, axis, points, faceVertexIndices, faceVertexCounts, holeIndices, orientation, doubleSided) and only when the prim carries a shape-consuming API such as PhysicsCollisionAPI. For a Sphere that is exactly radius. extent and normals are never published. A Sphere without a shape API gets a row only as an ancestor or relationship target, with no geometry.

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

radius

float64

length

1.0

resolved USD value (authored, else raw fallback)

1.0

Radius 1.0 (times the largest world-scale component). The consumer seeds the UsdGeomSphere fallback 1.0, which is also what the producer publishes for an unauthored attribute, so omitting the column is equivalent to USD population.

Derived values#

  • radius = abs(radius) * max(abs(worldScale.x), abs(worldScale.y), abs(worldScale.z)). The largest absolute component of the scale decomposed from the composed world transform. A non-uniform scale inflates the sphere to its largest axis; the runtime does not apply the transform scale again.

Interactions#

  • PhysicsCollisionAPI: Geometry is read only when the collision API is applied to this prim (or to a parent Xform that descends one level to this analytic child). extent is never read and never published.

Notes#

  • Type dispatch is by exact prim-type string on the geometry backing key, in the order Plane, custom-geometry token, Cube, Sphere, Capsule, Cylinder, Cone, Mesh.