Bug List:
---------
Priority 0-5, 5 is worst:

- [2] No sorting while alpha-blending. All opaque objects should be drawn before transparent. Turn off Z-buffer while drawing.
- [2] Face Culling does not work for boxes, when coordinates are flipped.
- [2] A self-refering cycle of rule retirements would crash structure synth.
- [2] Parser do not allow operator names as rule names. 'rule R1 maxdepth 2 > c ' fails.

Other TO-DO's:


