I'm now trying to make simple drawing tool using vertex and bezierVertex between beginShape and endShape.

I'm using arraylist to store the points to draw thick lines as a bezier shape. (So, to be accurate, drawing a long curving rectangles with bezier curves rather than drawing a single line)

The problem is when the bezier lines are crossing over, it will be negative (the white part in the image below).

I would like to have just a same color even when the line is crossing over.

If anyone could let me know how to avoid / hide this reverse or any suggestion for this, I would really appreciate your help.

Thanks in advance.