The path curve, which defines the N direction of the mesh, can be a line, arc, circle, ellipse, elliptical arc, 2D polyline, 3D polyline, or spline. If you select a circle, closed ellipse, or closed polyline, the mesh is closed in the N direction.
The direction vector can be a line or an open 2D or 3D polyline. If you choose a polyline, the vector sets the rotation axis from its first vertex to its last vertex. Any intermediate vertices are ignored. The axis of revolution determines the M direction of the mesh.
If you specify a nonzero start angle, the mesh is generated at a position offset from the path curve by that angle. The included angle specifies how far about the axis of revolution the mesh should extend.