This program partitions any 2d polygon into convex or near-convex regions.
It uses algorithm from R. Oliva and N. Pelechano - Automatic Generation of Suboptimal NavMeshes.
Launch demo_editor.py to see how it works.

demo_editor.py usage:
Place polygon points with left clicks, right click to finish creating the polygon. Self-intersections are not allowed.
Press plus or minus button in lower left corner to switch between addition and subtraction mode.

Camera controls:
ctrl + left mouse to pan
ctrl + right mouse to rotate
mouse wheel to zoom