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The panel's parameters are exactly the same for both modes, but the motion-depending settings are not available for passive rigid bodies, because they act like static obstacles.
Primitive
Each rigid body needs a surrounding geometry for collision detection and that is exactly what “Primitive” does. You can choose from various basic shapes or from exact representations of the active object. The less complex the selected shape, the faster the simulation will be calculated, but with simple approximations, accuracy is often not high enough and you might see interpenetration effects. For large amounts of objects or nodes with many polygons it will take a little time until the desired primitive type is applied. You can choose from 4 different shapes: “Sphere”, “Box”, “Convex Hull” and “Mesh”. The first two options can be used for nodes with an equivalent shape, while “Convex Hull” and “Mesh” are suited for more complex bodies. “Convex Hull” approximates the given shape with a bounding grid; “Mesh” exactly represents the entire object.
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