gdkglcontext-win32.c: Fix running with Mesa drivers

Some GL drivers such as Mesa-D3D12 do not allow one to call SetPixelFormat() on
a given HDC if one pixel format has been already set for it, so first check the
HDC with GetPixelFormat() to see whether a pixel format has already been set
with the HDC, and only attempt to acquire the pixel format if one has not been
set.

This will fix running with GL on Windows using the Mesa drivers.
This commit is contained in:
Chun-wei Fan 2021-04-29 12:04:42 +08:00
parent e024a542b0
commit 1b1dee86a5

View File

@ -855,19 +855,30 @@ _set_pixformat_for_hdc (HDC hdc,
const gboolean need_alpha_bits,
GdkWin32Display *display)
{
PIXELFORMATDESCRIPTOR pfd;
gboolean set_pixel_format_result = FALSE;
gboolean already_checked = TRUE;
*best_idx = GetPixelFormat (hdc);
/* one is only allowed to call SetPixelFormat(), and so ChoosePixelFormat()
* one single time per window HDC
*/
*best_idx = _get_wgl_pfd (hdc, need_alpha_bits, &pfd, display);
if (*best_idx != 0)
set_pixel_format_result = SetPixelFormat (hdc, *best_idx, &pfd);
if (*best_idx == 0)
{
PIXELFORMATDESCRIPTOR pfd;
gboolean set_pixel_format_result = FALSE;
/* ChoosePixelFormat() or SetPixelFormat() failed, bail out */
if (*best_idx == 0 || !set_pixel_format_result)
return FALSE;
GDK_NOTE (OPENGL, g_print ("requesting pixel format...\n"));
already_checked = FALSE;
*best_idx = _get_wgl_pfd (hdc, need_alpha_bits, &pfd, display);
if (*best_idx != 0)
set_pixel_format_result = SetPixelFormat (hdc, *best_idx, &pfd);
/* ChoosePixelFormat() or SetPixelFormat() failed, bail out */
if (*best_idx == 0 || !set_pixel_format_result)
return FALSE;
}
GDK_NOTE (OPENGL, g_print ("%s""requested and set pixel format: %d\n", already_checked ? "already " : "", *best_idx));
return TRUE;
}