static int
checkOverlayAcceptability(XVisualInfo * vi, unsigned int mode)
{
int value;
/* Must support OpenGL. */
glXGetConfig(__glutDisplay, vi, GLX_USE_GL, &value);
if (!value)
return 1;
/* Must be color index. */
glXGetConfig(__glutDisplay, vi, GLX_RGBA, &value);
if (value)
return 1;
/* Must match single/double buffering request. */
glXGetConfig(__glutDisplay, vi, GLX_DOUBLEBUFFER, &value);
if (GLUT_WIND_IS_DOUBLE(mode) != (value != 0))
return 1;
/* Must match mono/stereo request. */
glXGetConfig(__glutDisplay, vi, GLX_STEREO, &value);
if (GLUT_WIND_IS_STEREO(mode) != (value != 0))
return 1;
/* Alpha and accumulation buffers incompatible with color
index. */
if (GLUT_WIND_HAS_ALPHA(mode) || GLUT_WIND_HAS_ACCUM(mode))
return 1;
/* Look for depth buffer if requested. */
glXGetConfig(__glutDisplay, vi, GLX_DEPTH_SIZE, &value);
if (GLUT_WIND_HAS_DEPTH(mode) && (value <= 0))
return 1;
/* Look for stencil buffer if requested. */
glXGetConfig(__glutDisplay, vi, GLX_STENCIL_SIZE, &value);
if (GLUT_WIND_HAS_STENCIL(mode) && (value <= 0))
return 1;
#if defined(GLX_VERSION_1_1) && defined(GLX_SGIS_multisample)
/* XXX Multisampled overlay color index?? Pretty unlikely. */
/* Look for multisampling if requested. */
if (__glutIsSupportedByGLX("GLX_SGIS_multisample"))
glXGetConfig(__glutDisplay, vi, GLX_SAMPLES_SGIS, &value);
else
value = 0;
if (GLUT_WIND_IS_MULTISAMPLE(mode) && (value <= 0))
return 1;
#endif
return 0;
}
static XVisualInfo *
getVisualInfoRGB(unsigned int mode)
{
#if POKA
int list[32];
int n = 0;
/* Should not be looking at display mode mask if
__glutDisplayString is non-NULL. */
assert(!__glutDisplayString);
/* XXX Would a caching mechanism to minize the calls to
glXChooseVisual? You'd have to reference count
XVisualInfo* pointers. Would also have to properly
interact with glutInitDisplayString. */
list[n++] = GLX_RGBA;
list[n++] = GLX_RED_SIZE;
list[n++] = 1;
list[n++] = GLX_GREEN_SIZE;
list[n++] = 1;
list[n++] = GLX_BLUE_SIZE;
list[n++] = 1;
if (GLUT_WIND_HAS_ALPHA(mode)) {
list[n++] = GLX_ALPHA_SIZE;
list[n++] = 1;
}
if (GLUT_WIND_IS_DOUBLE(mode)) {
list[n++] = GLX_DOUBLEBUFFER;
}
if (GLUT_WIND_IS_STEREO(mode)) {
list[n++] = GLX_STEREO;
}
if (GLUT_WIND_HAS_DEPTH(mode)) {
list[n++] = GLX_DEPTH_SIZE;
list[n++] = 1;
}
if (GLUT_WIND_HAS_STENCIL(mode)) {
list[n++] = GLX_STENCIL_SIZE;
list[n++] = 1;
}
if (GLUT_WIND_HAS_ACCUM(mode)) {
list[n++] = GLX_ACCUM_RED_SIZE;
list[n++] = 1;
list[n++] = GLX_ACCUM_GREEN_SIZE;
list[n++] = 1;
list[n++] = GLX_ACCUM_BLUE_SIZE;
list[n++] = 1;
if (GLUT_WIND_HAS_ALPHA(mode)) {
list[n++] = GLX_ACCUM_ALPHA_SIZE;
list[n++] = 1;
}
}
#if defined(GLX_VERSION_1_1) && (defined(GLX_SGIS_multisample) || defined(GLX_ARB_multisample))
if (GLUT_WIND_IS_MULTISAMPLE(mode)) {
if (!__glutIsSupportedByGLX("GLX_SGIS_multisample") &&
!__glutIsSupportedByGLX("GLX_ARB_multisample"))
return NULL;
#if defined(GLX_ARB_multisample)
list[n++] = GLX_SAMPLES_ARB;
#elif defined(GLX_SGIS_multisample)
list[n++] = GLX_SAMPLES_SGIS;
#endif
/* XXX Is 4 a reasonable minimum acceptable number of
samples? */
list[n++] = 4;
}
#endif
list[n] = (int) None; /* terminate list */
return glXChooseVisual(__glutDisplay,
__glutScreen, list);
#else /* POKA */
return
glXChooseVisual(mode);
#endif
}
static XVisualInfo *
getVisualInfoRGB(unsigned int mode)
{
int list[32];
int n = 0;
/* Should not be looking at display mode mask if
__glutDisplayString is non-NULL. */
assert(!__glutDisplayString);
/* XXX Would a caching mechanism to minize the calls to
glXChooseVisual? You'd have to reference count
XVisualInfo* pointers. Would also have to properly
interact with glutInitDisplayString. */
list[n++] = GLX_RGBA;
list[n++] = GLX_RED_SIZE;
list[n++] = 1;
list[n++] = GLX_GREEN_SIZE;
list[n++] = 1;
list[n++] = GLX_BLUE_SIZE;
list[n++] = 1;
if (GLUT_WIND_HAS_ALPHA(mode)) {
list[n++] = GLX_ALPHA_SIZE;
list[n++] = 1;
}
if (GLUT_WIND_IS_DOUBLE(mode)) {
list[n++] = GLX_DOUBLEBUFFER;
}
if (GLUT_WIND_IS_STEREO(mode)) {
list[n++] = GLX_STEREO;
}
if (GLUT_WIND_HAS_DEPTH(mode)) {
list[n++] = GLX_DEPTH_SIZE;
list[n++] = 1;
}
if (GLUT_WIND_HAS_STENCIL(mode)) {
list[n++] = GLX_STENCIL_SIZE;
list[n++] = 1;
}
if (GLUT_WIND_HAS_ACCUM(mode)) {
list[n++] = GLX_ACCUM_RED_SIZE;
list[n++] = 1;
list[n++] = GLX_ACCUM_GREEN_SIZE;
list[n++] = 1;
list[n++] = GLX_ACCUM_BLUE_SIZE;
list[n++] = 1;
if (GLUT_WIND_HAS_ALPHA(mode)) {
list[n++] = GLX_ACCUM_ALPHA_SIZE;
list[n++] = 1;
}
}
/* GLX_SAMPLES_SGIS has the same value as GLX_SAMPLES_ARB. */
# ifndef GLX_SAMPLES_ARB
# define GLX_SAMPLES_ARB 100001
# endif
if (GLUT_WIND_IS_MULTISAMPLE(mode)) {
if (
#ifdef _WIN32
!has_WGL_ARB_multisample
#else
!__glutIsSupportedByGLX("GLX_SGIS_multisample") &&
!__glutIsSupportedByGLX("GLX_ARB_multisample")
#endif
) {
return NULL;
}
/* Accept either the SGIS or ARB GLX multisample extensions. */
list[n++] = GLX_SAMPLES_ARB;
list[n++] = 2;
}
list[n] = (int) None; /* terminate list */
return glXChooseVisual(__glutDisplay,
__glutScreen, list);
}
static XVisualInfo *
getVisualInfoRGB(unsigned int mode)
{
int list[32];
int n = 0;
/* XXX Would a caching mechanism to minize the calls to
glXChooseVisual? You'd have to reference count
XVisualInfo* pointers. */
list[n++] = GLX_RGBA;
list[n++] = GLX_RED_SIZE;
list[n++] = 1;
list[n++] = GLX_GREEN_SIZE;
list[n++] = 1;
list[n++] = GLX_BLUE_SIZE;
list[n++] = 1;
if (GLUT_WIND_HAS_ALPHA(mode)) {
list[n++] = GLX_ALPHA_SIZE;
list[n++] = 1;
}
if (GLUT_WIND_IS_DOUBLE(mode)) {
list[n++] = GLX_DOUBLEBUFFER;
}
if (GLUT_WIND_IS_STEREO(mode)) {
list[n++] = GLX_STEREO;
}
if (GLUT_WIND_HAS_DEPTH(mode)) {
list[n++] = GLX_DEPTH_SIZE;
list[n++] = 1;
}
if (GLUT_WIND_HAS_STENCIL(mode)) {
list[n++] = GLX_STENCIL_SIZE;
list[n++] = 1;
}
if (GLUT_WIND_HAS_ACCUM(mode)) {
list[n++] = GLX_ACCUM_RED_SIZE;
list[n++] = 1;
list[n++] = GLX_ACCUM_GREEN_SIZE;
list[n++] = 1;
list[n++] = GLX_ACCUM_BLUE_SIZE;
list[n++] = 1;
if (GLUT_WIND_HAS_ALPHA(mode)) {
list[n++] = GLX_ACCUM_ALPHA_SIZE;
list[n++] = 1;
}
}
#if defined(GLX_VERSION_1_1) && defined(GLX_SGIS_multisample)
if (GLUT_WIND_IS_MULTISAMPLE(mode)) {
if (!__glutIsSupportedByGLX("GLX_SGIS_multisample"))
return NULL;
list[n++] = GLX_SAMPLES_SGIS;
/* XXX Is 4 a reasonable minimum acceptable number of
samples? */
list[n++] = 4;
}
#endif
list[n] = (int) None; /* terminate list */
return glXChooseVisual(__glutDisplay,
__glutScreen, list);
}