Rigid Set Options

Name
Enter a name for your Rigid Set. Setting a name makes it easier to locate your set in the Outliner window. Be sure to choose a unique name, otherwise the command fails.
Create Input Set
Creates a set node that lets you edit the content of the set after you have created it. If you do not create an Input Set, you still get the geometry and transforms of the object cached in the initial state node but you cannot edit the contents of the initial state later or if you want to export the solved state to a baked simulation cache file (ABC bullet export).
Note: An input set is essential if you plan to export the simulation to an Alembic cache (ABC file).
Create Output Mesh
The Output Mesh creates a solved output mesh from the original source geometries. This lets you visualize the result of the simulation.
Note: Normal values and UV values are transferred but not materials or shaders. An alternative approach is to use the Bounding Box option found on the Bullet Solver node in the Attribute Editor.