internal override void CreateOffscreenDrawable (IntPtr handle,
int width, int height,
out object offscreen_drawable)
{
IntPtr root_out;
int x_out, y_out, width_out, height_out, border_width_out, depth_out;
XGetGeometry (DisplayHandle, handle,
out root_out,
out x_out, out y_out,
out width_out, out height_out,
out border_width_out, out depth_out);
IntPtr pixmap = XCreatePixmap (DisplayHandle, handle, width, height, depth_out);
offscreen_drawable = pixmap;
}