Hi @hotfooted ! 
I red and watched everything, and I finally understood your code!
However, when reviewing the created lines from
line(p1.x, p1.y, p2.x, p2.y);
It actually creates many many copies of the same line in the same place, so it does not create 1 constant vertex.
Here take a look for one of them
Is there a way to avoid it, to create one vertex from each origin, without making copies?