A python module that unfolds triangular surfaces onto the plane. The result can be used to create papercraft models.

The python bindings of OpenMesh are used and thus the original mesh can be loaded from any format supported by it. The output consists of several SVG files, each containing an intersection-free component of the unfolding.

• Python 3
• NumPy
• OpenMesh
• NetworkX

The usage is shown in testUnfold.py

Unfolding of the stanford bunny: The colors indicate the folding direction and the numbers the corresponding glued edge.

The algorithm consists of three steps:

1. Find a minimum spanning tree of the dual graph of the mesh.
2. Unfold the dual graph.
3. Remove self-intersections by adding additional cuts along edges.

The code is mostly based on the algorithm presented in this report by Straub and Prautzsch.

Because the original target audience was a group of German-speaking high-school students, many of the comments are written in German.

Felix Scholz [email protected]