The Geometry Parts () branch under Global Definitions has features to create a geometry Part in 3D (), 2D (), and 1D (). You can add these geometry parts as part instances in a geometry sequences in a Component. The Geometry Parts node appears when you add a geometry part by right-clicking the Global Definitions node and choosing a part from the Geometry Parts submenu.

A geometry part can be called (several times) from geometry sequences. You can use geometry parts to make custom parameterized geometric primitives. When calling a part, the input to the part is numerical values of its arguments. The output from the part is a number of geometry objects and a number of selections on these objects. The part node behaves like a geometry sequence with a few minor differences as described in the Using Geometry Parts section. You can also link a part from a Model MPH-file.