::Visual* Display::getVisual (VisualID visualID)
{
XVisualInfo info;
if (getVisualInfo(visualID, info))
return info.visual;
return DE_NULL;
}
XVisualInfo *
__glutDetermineVisual(
unsigned int displayMode,
Bool * treatAsSingle,
XVisualInfo * (getVisualInfo) (unsigned int))
{
XVisualInfo *vis;
/* Should not be looking at display mode mask if
__glutDisplayString is non-NULL. */
assert(!__glutDisplayString);
*treatAsSingle = GLUT_WIND_IS_SINGLE(displayMode);
vis = getVisualInfo(displayMode);
if (!vis) {
/* Fallback cases when can't get exactly what was asked
for... */
if (GLUT_WIND_IS_SINGLE(displayMode)) {
/* If we can't find a single buffered visual, try looking
for a double buffered visual. We can treat a double
buffered visual as a single buffer visual by changing
the draw buffer to GL_FRONT and treating any swap
buffers as no-ops. */
displayMode |= GLUT_DOUBLE;
vis = getVisualInfo(displayMode);
*treatAsSingle = True;
}
if (!vis && GLUT_WIND_IS_MULTISAMPLE(displayMode)) {
/* If we can't seem to get multisampling (ie, not Reality
Engine class graphics!), go without multisampling. It
is up to the application to query how many multisamples
were allocated (0 equals no multisampling) if the
application is going to use multisampling for more than
just antialiasing. */
displayMode &= ~GLUT_MULTISAMPLE;
vis = getVisualInfo(displayMode);
}
}
return vis;
}
