Polygons, Curves, Glyphs and more

For now, I'm very concentrated about set operations on polygons/curves.

I have the known articles about this theme. Some are not enough to degenerated cases, others have closure but are very hard to understand in deep or not so good for a "real" implementation.

I'm making my algorithm. By my math tests, it has closure if you know how to deal with the "bad" cases. Unfortunately, the implementation is getting infinite loop for some degenerated situations. How the coding has a lot of pointer indirections and the internal tasks are not so obvious, the debugging is a little bit hard. I suspect this behavior is coming from floating point imprecision. I should be very bad ... I hope I'm wrong.

Most of set operations in polygons can be "simulated" by correct use of layers. So, why this work? Cause I'm making my own code for font rendering also. I want to get a unique library for dealing with polygons, curves and font glyphs. A glyph can be very complex and usually you can understand it how a list of curves interacting by set operations. That's the reason.

Maybe I will not write here again until this part is done.