Sure. There’s no hurry for this. I’m very grateful that you are willing to actually spend any time on this idea at all!
I had to multiply p4 by -1 as Victor suggested. I also fixed a serious bug. It still doesn’t do error-checking and also I need to comment it. But -unless you find a bug- the syntax and the functionality should stay the same. I’m still not sure if control points should be allowed to overlap the regular points in Cabbage. Later on we should decide about that.
quadbezier_1.zip (1.5 KB)
I tried using a quadbezier table with gentable and the good news is that drawVerticalLine() seems to work fine.