QPixmap QXcbScreen::grabWindow(WId window, int x, int y, int width, int height) const
{
if (width == 0 || height == 0)
return QPixmap();
// TODO: handle multiple screens
QXcbScreen *screen = const_cast<QXcbScreen *>(this);
xcb_window_t root = screen->root();
if (window == 0)
window = root;
xcb_get_geometry_cookie_t geometry_cookie = xcb_get_geometry_unchecked(xcb_connection(), window);
xcb_get_geometry_reply_t *reply =
xcb_get_geometry_reply(xcb_connection(), geometry_cookie, NULL);
if (!reply) {
return QPixmap();
}
if (width < 0)
width = reply->width - x;
if (height < 0)
height = reply->height - y;
geometry_cookie = xcb_get_geometry_unchecked(xcb_connection(), root);
xcb_get_geometry_reply_t *root_reply =
xcb_get_geometry_reply(xcb_connection(), geometry_cookie, NULL);
if (!root_reply) {
free(reply);
return QPixmap();
}
if (reply->depth == root_reply->depth) {
// if the depth of the specified window and the root window are the
// same, grab pixels from the root window (so that we get the any
// overlapping windows and window manager frames)
// map x and y to the root window
xcb_translate_coordinates_cookie_t translate_cookie =
xcb_translate_coordinates_unchecked(xcb_connection(), window, root, x, y);
xcb_translate_coordinates_reply_t *translate_reply =
xcb_translate_coordinates_reply(xcb_connection(), translate_cookie, NULL);
if (!translate_reply) {
free(reply);
free(root_reply);
return QPixmap();
}
x = translate_reply->dst_x;
y = translate_reply->dst_y;
window = root;
free(translate_reply);
free(reply);
reply = root_reply;
} else {
free(root_reply);
root_reply = 0;
}
xcb_get_window_attributes_reply_t *attributes_reply =
xcb_get_window_attributes_reply(xcb_connection(), xcb_get_window_attributes_unchecked(xcb_connection(), window), NULL);
if (!attributes_reply) {
free(reply);
return QPixmap();
}
const xcb_visualtype_t *visual = screen->visualForId(attributes_reply->visual);
free(attributes_reply);
xcb_pixmap_t pixmap = xcb_generate_id(xcb_connection());
xcb_create_pixmap(xcb_connection(), reply->depth, pixmap, window, width, height);
uint32_t gc_value_mask = XCB_GC_SUBWINDOW_MODE;
uint32_t gc_value_list[] = { XCB_SUBWINDOW_MODE_INCLUDE_INFERIORS };
xcb_gcontext_t gc = xcb_generate_id(xcb_connection());
xcb_create_gc(xcb_connection(), gc, pixmap, gc_value_mask, gc_value_list);
xcb_copy_area(xcb_connection(), window, pixmap, gc, x, y, 0, 0, width, height);
QPixmap result = qt_xcb_pixmapFromXPixmap(connection(), pixmap, width, height, reply->depth, visual);
free(reply);
xcb_free_gc(xcb_connection(), gc);
xcb_free_pixmap(xcb_connection(), pixmap);
return result;
}
