Hey Rune! Nice to hear from you! :-)

> How about creating a bezier patch for each quad? Then the subdivision
level
> can easily be controlled. And there are macros that take exactly a 2d
array
> of points and create a bezier patch "cloth" from them, automatically
> creating all but the corner control points in the process (the corner
points
> being the ones that comes from the original 2d array).
SNIP

I thought about that and actually tried that when fiddling with bilinear
interpolation. I think I could come up with an implementation, shouldn't be
too difficult: calculate the control-nodes on the edges first and then
interpolate among the neighbours to get the inner control points (of course
keeping in mind that neighbouring patches need to have the same angle to the
edge to keep the edges smooth).
What's stuck in my head though when using bicubic-patches is their tendency
to fall apart when you go into too small and too large values (the usual
precision problem). But nontheless, I might go ahead and implement it
anyway, because it'll sure be of use to someone, and who knows, maybe it
*does* work for me, too! :-)

When you implemented this, did you have some paper as a guide, or did you
make it up yourself (which has a tendency these days to result in some
technique someone somewhere else has also come up with, sigh)? If you've
followed a paper, I'd be interested in it because of the mathematical
background like second order continuancy and such. If you did it yourself,
I'd be interested in the macro and maybe a short explanation how you came up
with it, and, if you still remember, what you tried and didn't work until
you ended up with the final version. You can send it via email, of course.
:-)

Thanks for the reply,
Tim

-- 
"Tim Nikias v2.0"
Homepage: <http://www.nolights.de>

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