[ghc-users removed from cc]
Btw, is there a way to reset the opengl system to a sane state in software? Or are there some invalid assumptions about default state in the other examples?
If OpenGL is getting "stuck" in a non-functional state, that indicates a bug in the driver.
quite possible. but I'm unlikely to get any driver updates for this model:-) still, driver bugs are not uncommon, so one might hope for a function to reinitialize OpenGL soft- and hardware (when workstations became less stable, they moved the reset button from the back to the front;). after all, reboot resets the configuration successfully, so there should be an easier way.. also, it is not completely non-functional, more like partially disabled, eg., after Tess segfault, running BezSurf shows only a black window, but running BezCurve shows the curve without the control points, and Double functions normally.. and as another data-point, if I let Tess segfault within gdb, this partial disabling does not happen at all - the other examples still run normally. if nothing else, HOpenGL should have a chance to contain the effects of this kind of bug on the OpenGL system, just as gdb does. just in case it is not just a driver bug: - I can run just the rectangle or just the triangle, but not just the star - I can run the rectangle, then the triangle, as separate tesselations and displaylists, but not both in one ComplexPolygon - apart from containing the side-effects, gdb bt isn't helping much: gluTessEndPolygon seems to make several nested calls to the older gluEndPolygon, everything else is unknown functions (??) Cheers, Claus sigh.. if today's notebook makers could spell quality-control, I'd have moved on long ago.