It takes polygonal data as input and generates polygonal data on output. The input dataset is swept according to some extrusion function and creates new polygonal primitives. There are a number of control parameters for this filter. The skirt is generated by locating certain topological features. This is true also of lines or polylines.
Vertices generate lines.
It also can be used to create solid objects from 2D polygonal meshes. When swept, this will result in two separate surfaces if capping is on, or no surface if capping is off. Only needs to be set if VectorExtrusion is turned on. Only needs to be set if PointExtrusion is turned on. This is the point towards which extrusion occurs.