At SciPy 2005, I thought I saw John show some examples of simple 3d surface plots in matplotlib. Is this code available?
Once you can draw points and lines on the screen, it's just a coordinate transform to make simple 3d plots (o.k. there are some hidden-line calculations too ).
The gist (in old scipy.xplt) package does simple 3d using just the 2d primitives.