Hi Marco & eric - it's getting awfully close! I've got a good path forward for the viewport display, I've been able to modify the rendering library so it matches up with what I need to do and I've got curves and surfaces drawing on screen now.

The main areas left are shaders, background images and text labels, hit testing, and more exploration of a fast path for high memory video cards. I've been thinking that I might release an early version before all that stuff is completely done.

Here's what it looks like at the moment (model by PaQ):



- Michael