XVisualInfo *qglx_findVisualInfo(Display *display, int screen, QSurfaceFormat *format)
{
Q_ASSERT(format);
XVisualInfo *visualInfo = 0;
GLXFBConfig config = qglx_findConfig(display,screen,*format);
if (config) {
visualInfo = glXGetVisualFromFBConfig(display, config);
*format = qglx_surfaceFormatFromGLXFBConfig(display, config);
}
// attempt to fall back to glXChooseVisual
bool reduced = true;
QSurfaceFormat reducedFormat = *format;
while (!visualInfo && reduced) {
QVarLengthArray<int, 13> attribs;
attribs.append(GLX_RGBA);
if (reducedFormat.redBufferSize() > 0) {
attribs.append(GLX_RED_SIZE);
attribs.append(reducedFormat.redBufferSize());
}
if (reducedFormat.greenBufferSize() > 0) {
attribs.append(GLX_GREEN_SIZE);
attribs.append(reducedFormat.greenBufferSize());
}
if (reducedFormat.blueBufferSize() > 0) {
attribs.append(GLX_BLUE_SIZE);
attribs.append(reducedFormat.blueBufferSize());
}
if (reducedFormat.stencilBufferSize() > 0) {
attribs.append(GLX_STENCIL_SIZE);
attribs.append(reducedFormat.stencilBufferSize());
}
if (reducedFormat.depthBufferSize() > 0) {
attribs.append(GLX_DEPTH_SIZE);
attribs.append(reducedFormat.depthBufferSize());
}
if (reducedFormat.swapBehavior() != QSurfaceFormat::SingleBuffer)
attribs.append(GLX_DOUBLEBUFFER);
attribs.append(XNone);
visualInfo = glXChooseVisual(display, screen, attribs.data());
if (visualInfo)
*format = reducedFormat;
reducedFormat = qglx_reduceSurfaceFormat(reducedFormat, &reduced);
}
return visualInfo;
}
GLXFBConfig qglx_findConfig(Display *display, int screen , const QSurfaceFormat &format, int drawableBit)
{
bool reduced = true;
GLXFBConfig chosenConfig = 0;
QSurfaceFormat reducedFormat = format;
while (!chosenConfig && reduced) {
QVector<int> spec = qglx_buildSpec(reducedFormat, drawableBit);
int confcount = 0;
GLXFBConfig *configs;
configs = glXChooseFBConfig(display, screen,spec.constData(),&confcount);
if (confcount)
{
for (int i = 0; i < confcount; i++) {
chosenConfig = configs[i];
// Make sure we try to get an ARGB visual if the format asked for an alpha:
if (reducedFormat.hasAlpha()) {
int alphaSize;
glXGetFBConfigAttrib(display,configs[i],GLX_ALPHA_SIZE,&alphaSize);
if (alphaSize > 0) {
XVisualInfo *visual = glXGetVisualFromFBConfig(display, chosenConfig);
bool hasAlpha = false;
#if !defined(QT_NO_XRENDER)
XRenderPictFormat *pictFormat = XRenderFindVisualFormat(display, visual->visual);
hasAlpha = pictFormat->direct.alphaMask > 0;
#else
hasAlpha = visual->depth == 32;
#endif
XFree(visual);
if (hasAlpha)
break;
}
} else {
break; // Just choose the first in the list if there's no alpha requested
}
}
XFree(configs);
}
if (!chosenConfig)
reducedFormat = qglx_reduceSurfaceFormat(reducedFormat,&reduced);
}
return chosenConfig;
}
GLXFBConfig qglx_findConfig(Display *display, int screen , const QSurfaceFormat &format, int drawableBit)
{
// Allow forcing LIBGL_ALWAYS_SOFTWARE for Qt 5 applications only.
// This is most useful with drivers that only support OpenGL 1.
// We need OpenGL 2, but the user probably doesn't want
// LIBGL_ALWAYS_SOFTWARE in OpenGL 1 apps.
static bool checkedForceSoftwareOpenGL = false;
static bool forceSoftwareOpenGL = false;
if (!checkedForceSoftwareOpenGL) {
// If LIBGL_ALWAYS_SOFTWARE is already set, don't mess with it.
// We want to unset LIBGL_ALWAYS_SOFTWARE at the end so it does not
// get inherited by other processes, of course only if it wasn't
// already set before.
if (!qEnvironmentVariableIsEmpty("QT_XCB_FORCE_SOFTWARE_OPENGL")
&& !qEnvironmentVariableIsSet("LIBGL_ALWAYS_SOFTWARE"))
forceSoftwareOpenGL = true;
checkedForceSoftwareOpenGL = true;
}
if (forceSoftwareOpenGL)
qputenv("LIBGL_ALWAYS_SOFTWARE", QByteArrayLiteral("1"));
bool reduced = true;
GLXFBConfig chosenConfig = 0;
QSurfaceFormat reducedFormat = format;
while (!chosenConfig && reduced) {
QVector<int> spec = qglx_buildSpec(reducedFormat, drawableBit);
int confcount = 0;
GLXFBConfig *configs;
configs = glXChooseFBConfig(display, screen,spec.constData(),&confcount);
if (confcount)
{
for (int i = 0; i < confcount; i++) {
chosenConfig = configs[i];
// Make sure we try to get an ARGB visual if the format asked for an alpha:
if (reducedFormat.hasAlpha()) {
int alphaSize;
glXGetFBConfigAttrib(display,configs[i],GLX_ALPHA_SIZE,&alphaSize);
if (alphaSize > 0) {
XVisualInfo *visual = glXGetVisualFromFBConfig(display, chosenConfig);
bool hasAlpha = false;
#if !defined(QT_NO_XRENDER)
XRenderPictFormat *pictFormat = XRenderFindVisualFormat(display, visual->visual);
hasAlpha = pictFormat->direct.alphaMask > 0;
#else
hasAlpha = visual->depth == 32;
#endif
XFree(visual);
if (hasAlpha)
break;
}
} else {
break; // Just choose the first in the list if there's no alpha requested
}
}
XFree(configs);
}
if (!chosenConfig)
reducedFormat = qglx_reduceSurfaceFormat(reducedFormat,&reduced);
}
// unset LIBGL_ALWAYS_SOFTWARE now so other processes don't inherit it
if (forceSoftwareOpenGL)
qunsetenv("LIBGL_ALWAYS_SOFTWARE");
return chosenConfig;
}
