Overlapping Paths

[Ofnuts]

Hmmm. Having more questions than answers right now.

• Techniques that do a single mask of outlines and a single mask of holes don't work in cases where there is an outline inside a hole, for instance the dotted zero shown above, or a nearby character that overlaps the hole in another.
  
• Processing strokes in sequence (adding outlines, removing holes) would at least work for the dotted zero case, but not for the overlap if the overlapping character appears first (which is unfortunately the more frequent case)
  
• A bit of experimenting shows that when you edit a stroke if goes to the end of the strokes list, so it can solve the overlap issue (the overlapping character is drawn last), however this applies to the stroke and not to the character, so if the character has holes, the holes are going to be drawn out of sequence and will be filled when the outline stroke is eventually drawn. So the sequencing algorithm is not very robust with an edited path (not speaking of strokes where the orientation gets changed by the editing).
  

The conclusion is that whatever I do, the doc for all the caveats, pitfalls and restrictions if going to take longer to write than the code. I just hope that some people will read it.