In Rose (mathematics) - Wikipedia you can find a key to low-order parameters: n and d here are
b in my model, respectively):
I have a specific use case that requires angled sides. I’m trying to make aluminum rosette “irons” which require some draft angle so that the rosettes can be removed from the iron after cooking. Therefore, my code allows you to set a draft angle; this allows the top surface to be a different thickness from the bottom surface. If this angle is 0° the pipe will have a rectangular cross-section.
Draft angle is useful for molding in general. So whether you are 3D printing a part to burn out for investment casting, making a mold for green sand casting, making a rosette iron, or making a mold for casting plastic, you need some angle on the sides to get the part out of or off the mold.
radius parameter is the minimal radius of a cylinder centered at the origin and enclosing the center line of the part. Therefore, the part will have an effective radius of the specified radius plus half the specified thickness which is the thickness of the line at the base of the part.