Looked into unwrap for a cone, and used MoI to make a sketch of some of the mathematics.
Unwrap gives the circumference length of a circle. Flow of the unwrap line to a circle with the slant height radius "s" creates the unwrapped base.
The formulas are also said to work for cylinders. The conical frustrum is a cone with the "top" cut off.
Two references are archaeological. The papers are free on the internet.
Unwrapping HighlyDetailed 3D Meshed of
Rotationally Symmetric ManMade Objects
Bastian Rieck, Hubert Mara, and Susanne Kr..omker
Rollouts of Fine Ware Pottery using High Resolution 3D Meshes
S. Bechtold and S. Krömker and H. Mara and B. Kratzmüller
Unwrapping Curves from Cylinders and Cones
Tom M. Apostol and Mamikon A. Mnatsakanian
May try to do a script.
 Brian
