[PATCH 0/1] MR9546: winex11: Flush after presenting.

[PATCH 1/1] winex11: Flush after presenting.

[Elizabeth Figura]

From: Elizabeth Figura

The following cause an image to be immediately visible on Windows:

* Direct3D Present()

* wglSwapBuffers() [after drawing to the back buffer]

* glFlush() [after drawing to the front buffer. Note that glFlush() is both
  necessary and sufficient.]

* vkQueuePresent()

This is all of the paths that ultimately call client_surface_present().

In order to ensure that pixels are immediately visible on Wine as well, we need
to flush immediately after presenting.

Based on a patch by Henri Verbeet.
---
 dlls/winex11.drv/init.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/dlls/winex11.drv/init.c b/dlls/winex11.drv/init.c
index 1ea51e9a387..f6fe0aed894 100644
--- a/dlls/winex11.drv/init.c
+++ b/dlls/winex11.drv/init.c
@@ -415,6 +415,7 @@ static void X11DRV_client_surface_present( struct client_surface *client, HDC hd

NtGdiStretchBlt( surface->hdc_dst, 0, 0, rect_dst.right - rect_dst.left, rect_dst.bottom - rect_dst.top,
                      surface->hdc_src, 0, 0, surface->rect.right, surface->rect.bottom, SRCCOPY, 0 );
+    XFlush( gdi_display );

done:
     if (region) NtGdiDeleteObjectApp( region );

[Elizabeth Figura (＠zfigura)]

I'm attaching the standalone tests I was using to demonstrate this. They clear to blue when pressing down on the mouse, and green when releasing it. With upstream Wine, they are always one frame behind. [This is actually regardless of whether a parent or child window is used; I wanted to test both cases.]

[presenttest.c](/uploads/efd8ffcb2dcdbd30d7f46e9861ad91b8/presenttest.c)

[presenttest-gl.c](/uploads/03983e80b53ddaf2eb52f36a769e58bc/presenttest-gl.c)

[presenttest-vulkan.c](/uploads/38b761d314043dff80714ad995574a3e/presenttest-vulkan.c)