Question

Recently I’ve been thinking about how to transform a complex polygon into a non-complex polygon. How is this done?

This is the sort of thing I want to do:

I’m going to end up with JavaScript when I’m done, but any form of a solution is fine (language, algorithm, or just plain English).

Answer 1

I would use the same heuristic that I would use when drawing the polygon by hand (which is probably not the most mathematically efficient way to caluclaute that polygon, but probably the easiest to understand/implement).

1. Start at a point
2. Find all the intersections between my current point and the point I’m trying to get to
3. If none exist draw to the next point
4. If one does, then draw to there, and then set the next point to the next point from there
5. If you aren’t back to the beginning then goto 2.

Here is an example implementation on jsfiddle. Note: it isn’t optimized.