The radius of particle shapes in Softimage units.
This is used for display and rendering, as well as by the Simulate Rigid Bodies node for determining collisions if CollisionSize is undefined.
If both this attribute and CollisionSize are undefined, the default value used by the Simulate Rigid Bodies node is 0.001.
You can quickly get and set the Size attribute with the Get Particle Size and Set Particle Size compounds.
For point and segment shapes, ShapeSizeAbsolute controls whether this value is interpreted as Softimage units or pixels.
