OpenGL surface graph, TeeChart ProAX v5

Run on TeeChart ProAX v5 within excel - nice tool all can say...

I've drawn a 3D surface graph and found that it doesn't correctly draw
hidden surface. Sometime they overlap and are drown on top of
frontface surface, depends on how you turn the surface around.
Another thing, you have to re sort the surfaces if you have say three
surfaces stacked up(doesn't touch each other). Otherwise it will draw
the bottom surface on to of the  top surface. So everything will be
messed up.

I have GeForce2go, WinXP, OfficeXP, Dell laptop 8100
Run on TeeChart ProAX v5 within excel - nice tool all can say...

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suggest - for surface graphs - make custom pallete setup, custom
values, instead just from, mid, to colors. And make it based on the
altitude, not just blend it betwean min amd max.

E