Create a surface by sweeping a shape curve over a rail curve.

Input parameters:

1. Sc → Sweep section curves.
2. Rl → Sweep rail curve.
3. Nr → Optional frame normal vector. When set, the sweep type is 'road-like' rather than 'free-form'.
4. Gl → If true, the blending between adjacent sections is .
5. Mi → If true, miters due to kinks in the rail curve become trimmed surfaces.
6. Pa → Optional start point of lofted surface.
7. Pb → Optional end point of lofted surface.
8. Rb → Optional rebuild control point count. If omitted, the resulting surface will not be rebuild.
9. Rf → Optional refit tolerance. If omitted, the resulting surface will not be refitted.

Output parameters:

1. Sf → Sweep surface based on rail and shape curves.