[HOpenGL] Re: OpenGL/GLUT examples crashing: known problem?

[Claus Reinke]

[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.