[PyQt] max texture size for QGLWidget.bindTexture?

[Brian Parma]

I've noticed that If I try to use bindTexture on QPixmaps that are large 
(the size of the screen), and then display them on a quad, only a 
portion of the texture actually shows.  The rest of the surface is 
either black or a scrambled jumble of other textures.  If I use a 
smaller image there is no problem, but I can't find any references to a 
max texture size in the documentation.  I tried increasing the texture 
cache size but that had no effect.  Is there a limit on texture size, 
and if so, how do you determine it?