Create a tapering deformation. If an input shape is provided, it will be deformed accordingly.

Input parameters:

1. Sh → Optional shape to taper.
2. Ax → Tapering axis.
3. R1 → Radius at the start of the taper axis.
4. R2 → Radius at the end of the taper axis.
5. In → If true, the taper deformation extends infinitely beyond the limits of the axis.

Output parameters:

1. Sh → Shape with applied deformation.
2. Df → Tapering deformation.