wgl: Add stw_winsys callback to check which PFD flags should be added

Reviewed-by: Charmaine Lee <charmainel@vmware.com>
Reviewed-by: Erik Faye-Lund <erik.faye-lund@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7535>

src/gallium/frontends/wgl/stw_winsys.h

@@ -38,6 +38,12 @@ struct pipe_resource;
 
 struct stw_shared_surface;
 
+typedef enum
+{
+   stw_pfd_gdi_support   = 1 << 0,
+   stw_pfd_double_buffer = 1 << 1,
+} stw_pfd_flag;
+
 struct stw_winsys
 {
    struct pipe_screen *
@@ -91,6 +97,13 @@ struct stw_winsys
                struct stw_shared_surface *dest,
                LPCRECT pRect,
                ULONGLONG PresentHistoryToken );
+
+   /**
+    * Query whether the driver can support GDI and/or double-buffering in its
+    * pixel formats (optional).
+    */
+   unsigned
+   (*get_pfd_flags)( struct pipe_screen *screen );
 };
 
 boolean

src/gallium/targets/libgl-d3d12/libgl_d3d12.c

@@ -84,13 +84,21 @@ gdi_get_adapter_luid(struct pipe_screen *screen,
 }
 
 
+static unsigned
+gdi_get_pfd_flags(struct pipe_screen *screen)
+{
+   return d3d12_wgl_get_pfd_flags(screen);
+}
+
+
 static const struct stw_winsys stw_winsys = {
    &gdi_screen_create,
    &gdi_present,
    &gdi_get_adapter_luid,
    NULL, /* shared_surface_open */
    NULL, /* shared_surface_close */
-   NULL  /* compose */
+   NULL, /* compose */
+   &gdi_get_pfd_flags
 };
 
 

src/gallium/targets/libgl-gdi/libgl_gdi.c

@@ -218,6 +218,17 @@ gdi_get_adapter_luid(struct pipe_screen* screen,
 #endif
 
 
+static unsigned
+gdi_get_pfd_flags(struct pipe_screen *screen)
+{
+#ifdef GALLIUM_D3D12
+   if (use_d3d12)
+      return d3d12_wgl_get_pfd_flags(screen);
+#endif
+   return stw_pfd_gdi_support;
+}
+
+
 static const struct stw_winsys stw_winsys = {
    &gdi_screen_create,
    &gdi_present,
@@ -228,7 +239,8 @@ static const struct stw_winsys stw_winsys = {
 #endif
    NULL, /* shared_surface_open */
    NULL, /* shared_surface_close */
-   NULL  /* compose */
+   NULL, /* compose */
+   &gdi_get_pfd_flags,
 };
 
 

src/gallium/winsys/d3d12/wgl/d3d12_wgl_public.h

@@ -43,6 +43,9 @@ d3d12_wgl_present(struct pipe_screen *screen,
                   struct pipe_resource *res,
                   HDC hDC);
 
+unsigned
+d3d12_wgl_get_pfd_flags(struct pipe_screen *screen);
+
 #ifdef __cplusplus
 }
 #endif

src/gallium/winsys/d3d12/wgl/d3d12_wgl_winsys.c

@@ -48,3 +48,10 @@ d3d12_wgl_present(struct pipe_screen *screen,
 {
    screen->flush_frontbuffer(screen, res, 0, 0, hDC, NULL);
 }
+
+unsigned
+d3d12_wgl_get_pfd_flags(struct pipe_screen *screen)
+{
+   (void)screen;
+   return stw_pfd_gdi_support;
+}