GLXFBConfig GLXGLSupport::getFBConfigFromContext(::GLXContext context)
{
GLXFBConfig fbConfig = 0;
if (GLXEW_VERSION_1_3)
{
int fbConfigAttrib[] = {
GLX_FBCONFIG_ID, 0,
None
};
GLXFBConfig *fbConfigs;
int nElements = 0;
glXQueryContext(mGLDisplay, context, GLX_FBCONFIG_ID, &fbConfigAttrib[1]);
fbConfigs = glXChooseFBConfig(mGLDisplay, DefaultScreen(mGLDisplay), fbConfigAttrib, &nElements);
if (nElements)
{
fbConfig = fbConfigs[0];
XFree(fbConfigs);
}
}
else if (GLXEW_EXT_import_context && GLXEW_SGIX_fbconfig)
{
VisualID visualid;
if (glXQueryContextInfoEXT(mGLDisplay, context, GLX_VISUAL_ID, (int*)&visualid))
{
fbConfig = getFBConfigFromVisualID(visualid);
}
}
return fbConfig;
}
static bool
try_query(GLXContext ctx, int attribute, const char *attribute_string,
int expected_error, int expected_value)
{
bool pass = true;
int value = 0xDEADBEEF;
int err;
err = glXQueryContextInfoEXT(dpy, ctx, attribute, &value);
XSync(dpy, 0);
if (err != expected_error) {
fprintf(stderr,
"Query of %s had error %d, but %d was expected.\n",
attribute_string,
err,
expected_error);
pass = false;
}
/* There is no way in GLX_SGIX_fbconfig to get an XID from a
* GLXFBConfig. As a result, there's no way to verify
* glXQueryContextInfoEXT has returned the correct value. The
* required functionality was not added until GLX 1.3.
*/
if (attribute != GLX_FBCONFIG_ID_SGIX) {
if (expected_error != Success)
expected_value = 0xDEADBEEF;
if (value != expected_value) {
fprintf(stderr,
"Query of %s had value %d, but %d was "
"expected.\n",
attribute_string,
value,
expected_value);
pass = false;
}
} else {
if (value == 0xDEADBEEF) {
fprintf(stderr,
"Query of %s did not set a value.\n",
attribute_string);
pass = false;
}
}
/* No GLX protocol error should be generated.
*/
pass = validate_glx_error_code(Success, -1) && pass;
return pass;
}