QGLGraphicsSystem::QGLGraphicsSystem(bool useX11GL)
: QGraphicsSystem(), m_useX11GL(useX11GL)
{
#if defined(Q_WS_X11) && !defined(QT_OPENGL_ES)
// only override the system defaults if the user hasn't already
// picked a visual
if (X11->visual == 0 && X11->visual_id == -1 && X11->visual_class == -1) {
// find a double buffered, RGBA visual that supports OpenGL
// and set that as the default visual for windows in Qt
int i = 0;
int spec[16];
spec[i++] = GLX_RGBA;
spec[i++] = GLX_DOUBLEBUFFER;
if (!qgetenv("QT_GL_SWAPBUFFER_PRESERVE").isNull()) {
spec[i++] = GLX_DEPTH_SIZE;
spec[i++] = 8;
spec[i++] = GLX_STENCIL_SIZE;
spec[i++] = 8;
spec[i++] = GLX_SAMPLE_BUFFERS_ARB;
spec[i++] = 1;
spec[i++] = GLX_SAMPLES_ARB;
spec[i++] = 4;
}
spec[i++] = XNone;
XVisualInfo *vi = glXChooseVisual(X11->display, X11->defaultScreen, spec);
if (vi) {
X11->visual_id = vi->visualid;
X11->visual_class = vi->c_class;
QGLFormat format;
int res;
glXGetConfig(X11->display, vi, GLX_LEVEL, &res);
format.setPlane(res);
glXGetConfig(X11->display, vi, GLX_DOUBLEBUFFER, &res);
format.setDoubleBuffer(res);
glXGetConfig(X11->display, vi, GLX_DEPTH_SIZE, &res);
format.setDepth(res);
if (format.depth())
format.setDepthBufferSize(res);
glXGetConfig(X11->display, vi, GLX_RGBA, &res);
format.setRgba(res);
glXGetConfig(X11->display, vi, GLX_RED_SIZE, &res);
format.setRedBufferSize(res);
glXGetConfig(X11->display, vi, GLX_GREEN_SIZE, &res);
format.setGreenBufferSize(res);
glXGetConfig(X11->display, vi, GLX_BLUE_SIZE, &res);
format.setBlueBufferSize(res);
glXGetConfig(X11->display, vi, GLX_ALPHA_SIZE, &res);
format.setAlpha(res);
if (format.alpha())
format.setAlphaBufferSize(res);
glXGetConfig(X11->display, vi, GLX_ACCUM_RED_SIZE, &res);
format.setAccum(res);
if (format.accum())
format.setAccumBufferSize(res);
glXGetConfig(X11->display, vi, GLX_STENCIL_SIZE, &res);
format.setStencil(res);
if (format.stencil())
format.setStencilBufferSize(res);
glXGetConfig(X11->display, vi, GLX_STEREO, &res);
format.setStereo(res);
glXGetConfig(X11->display, vi, GLX_SAMPLE_BUFFERS_ARB, &res);
format.setSampleBuffers(res);
if (format.sampleBuffers()) {
glXGetConfig(X11->display, vi, GLX_SAMPLES_ARB, &res);
format.setSamples(res);
}
QGLWindowSurface::surfaceFormat = format;
XFree(vi);
printf("using visual class %x, id %x\n", X11->visual_class, X11->visual_id);
}
}
#elif defined(Q_WS_WIN)
QGLWindowSurface::surfaceFormat.setDoubleBuffer(true);
qt_win_owndc_required = true;
#endif
}
