GUI fans might want to start tracking the Cello list for ongoing development.
Celtk is fine and with its Togl widget even does OpenGL, but Cello makes the Celtk/Togl come alive with:
FTGL -- anti-aliased texture, polygon, outline, pixmap, bitmap, extruded, and one I ma forgetting fonts
GraphicsMagick/ImageMagick -- awesome graphic file handling and more
OpenAL -- fun with 3D sound
Much more sophisticate dframework, esp. in re widget Geometry.
Speaking of OpenAL, it looks as if the Tcl "Snack" library will provide terrific real-time audio synthesis (but that would be true for Celtk as well).
Anyway, if you download Cello now (a) most of it is yet to be resurrected but (b) if you can get demo NeHe-06 running (1) you are pretty good at getting hairy libraries running and (2) i think you will enjoy it. :)
Meanwhile, PyCells is bringing some attention this way:
http://www.eby-sarna.com/pipermail/peak/2006-May/002545.html
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