OpenGL. Yeah I didn't find it too great of an experience. Especially after finding out the myriad devices that are needed to support and their different OpenGL frameworks. Ended up just doing a PoC but gave up around the time I had to do the actual maths. With holidays coming up maybe I'll give it another shot. There's a company I think would find the app useful so it has a commercial reality too! Will check back in with you to see how you're going if I remember