ouch. KISS straight out the second story window. You bet, I'm game. Single draw call per primitive type you say. yup that sounds good. I suppose this is a great opportunity to finally experiment with glBufferSubData and friends. I'd have to learn how to not draw a range when an end is being dragged and maybe have a separate 'selected/editing' buffer ping/pong thing. My color comes from uniform so there is something else to ponder to not loose onHover behavior.I am liking t