OmniGraph Physics Immediate Nodes

Immediate Nodes belong to a special category of OmniGraph Physics nodes.

The main notable differences with the Scene Nodes are the following:

• Immediate nodes don’t need a running Simulation or Scene in order to work

• Immediate nodes don’t need simulation stepping

• Immediate nodes don’t need USD Physics API applied to Prims

• Immediate nodes can work with procedurally generated prims that only exist inside OmniGraph / Fabric (avoiding touching USD completely)

Coarse Intersection Detection (broadphase-like)

• Compute Geometry Bounds

• Compute Bounds Overlaps

Detailed Intersection Detection

• Compute Geometry Penetrations

• Compute Geometry Overlaps

• Compute Mesh Intersecting Faces

Contacts Generation

• Generate Geometry Contacts

All Immediate Nodes currently operate on Prims bundles, for example as output by the Read Prims node, or by procedurally creating Bundle Prims using other OmniGraph bundle manipulation nodes.

Important

Immediate nodes currently only support Mesh USD Prims, and not Shape USD prims.

Note

It’s more efficient to use a single node with multiple input Prims than multiple nodes with a single Prim. The reason is that the single node has smaller overhead on overall Graph execution and it processes all meshes in parallel anyway.

Note

Immediate nodes can be easily accessed from Python by leveraging regular OmniGraph Python API and evaluating the graph at each needed step to extract results from it.