GlxContext::GlxContext(GlxContext* shared) :
m_window (0),
m_context (NULL),
m_ownsWindow(true)
{
// Open a connection with the X server
m_display = OpenDisplay();
m_connection = XGetXCBConnection(m_display);
xcb_screen_t* screen = XCBScreenOfDisplay(m_connection, DefaultScreen(m_display));
// Choose the visual according to the context settings
XVisualInfo visualInfo = selectBestVisual(m_display, VideoMode::getDesktopMode().bitsPerPixel, ContextSettings());
// Define the window attributes
xcb_colormap_t colormap = xcb_generate_id(m_connection);
xcb_create_colormap(m_connection, XCB_COLORMAP_ALLOC_NONE, colormap, screen->root, visualInfo.visualid);
const uint32_t value_list[] = {colormap};
// Create a dummy window (disabled and hidden)
m_window = xcb_generate_id(m_connection);
xcb_create_window(
m_connection,
static_cast<uint8_t>(visualInfo.depth),
m_window,
screen->root,
0, 0,
1, 1,
0,
XCB_WINDOW_CLASS_INPUT_OUTPUT,
visualInfo.visualid,
XCB_CW_COLORMAP,
value_list
);
// Create the context
createContext(shared, VideoMode::getDesktopMode().bitsPerPixel, ContextSettings());
}
void GlxContext::createSurface(GlxContext* shared, unsigned int width, unsigned int height, unsigned int bitsPerPixel)
{
m_display = OpenDisplay();
m_connection = XGetXCBConnection(m_display);
// Choose the visual according to the context settings
XVisualInfo visualInfo = selectBestVisual(m_display, bitsPerPixel, m_settings);
// Check if the shared context already exists and pbuffers are supported
if (shared && (sfglx_ext_SGIX_pbuffer == sfglx_LOAD_SUCCEEDED))
{
// There are no GLX versions prior to 1.0
int major = 0;
int minor = 0;
glXQueryVersion(m_display, &major, &minor);
// Check if glXCreatePbuffer is available (requires GLX 1.3 or greater)
bool hasCreatePbuffer = ((major > 1) || (minor >= 3));
if (hasCreatePbuffer)
{
// Get a GLXFBConfig that matches the visual
GLXFBConfig* config = NULL;
// We don't supply attributes to match against, since
// the visual we are matching against was already
// deemed suitable in selectBestVisual()
int nbConfigs = 0;
GLXFBConfig* configs = glXChooseFBConfig(m_display, DefaultScreen(m_display), NULL, &nbConfigs);
for (int i = 0; configs && (i < nbConfigs); ++i)
{
XVisualInfo* visual = glXGetVisualFromFBConfig(m_display, configs[i]);
if (!visual)
continue;
if (visual->visualid == visualInfo.visualid)
{
config = &configs[i];
break;
}
}
if (config)
{
int attributes[] =
{
GLX_PBUFFER_WIDTH, static_cast<int>(width),
GLX_PBUFFER_HEIGHT, static_cast<int>(height),
0, 0
};
m_pbuffer = glXCreatePbuffer(m_display, *config, attributes);
updateSettingsFromVisualInfo(&visualInfo);
XFree(configs);
return;
}
if (configs)
XFree(configs);
}
}
// If pbuffers are not available we use a hidden window as the off-screen surface to draw to
xcb_screen_t* screen = XCBScreenOfDisplay(m_connection, DefaultScreen(m_display));
// Define the window attributes
xcb_colormap_t colormap = xcb_generate_id(m_connection);
xcb_create_colormap(m_connection, XCB_COLORMAP_ALLOC_NONE, colormap, screen->root, visualInfo.visualid);
const uint32_t value_list[] = {colormap};
// Create a dummy window (disabled and hidden)
m_window = xcb_generate_id(m_connection);
xcb_create_window(
m_connection,
static_cast<uint8_t>(visualInfo.depth),
m_window,
screen->root,
0, 0,
width, height,
0,
XCB_WINDOW_CLASS_INPUT_OUTPUT,
visualInfo.visualid,
XCB_CW_COLORMAP,
value_list
);
m_ownsWindow = true;
updateSettingsFromWindow();
}
