Merge branch 'win32-gl-fullscreen-workaround-gtk3' into 'gtk-3-24'

gdkwindow-win32.c: Set WS_BORDER for fullscreen GL windows if requested

See merge request GNOME/gtk!648

1 files changed, 22 insertions, 3 deletions

diff --git a/gdk/win32/gdkwindow-win32.c b/gdk/win32/gdkwindow-win32.c
index 3951387e19..cf416d8e2a 100644
--- a/gdk/win32/gdkwindow-win32.c
+++ b/gdk/win32/gdkwindow-win32.c
@@ -5312,6 +5312,8 @@ gdk_win32_window_fullscreen (GdkWindow *window)
   FullscreenInfo *fi;
   HMONITOR monitor;
   MONITORINFO mi;
+  DWORD extra_styles = WS_POPUP;
+  gint workaround_padding = 0;
 
   g_return_if_fail (GDK_IS_WINDOW (window));
 
@@ -5348,12 +5350,29 @@ gdk_win32_window_fullscreen (GdkWindow *window)
       /* Send state change before configure event */
       gdk_synthesize_window_state (window, 0, GDK_WINDOW_STATE_FULLSCREEN);
 
+      /* If we are using GL windows, and we set the envvar GDK_WIN32_GL_FULLSCREEN_WORKAROUND,
+       * set the WS_BORDER style so that DWM will not get deactivated.  This is necessary
+       * when menus could not be shown correctly in fullscreen GL windows.  To avoid seeing
+       * a border, we intentionally make the window bigger by 1px on all sides and place the
+       * window just 1px outside the top left-hand coordinates outside the screen area.
+       */
+      if (window->gl_paint_context != NULL && g_getenv ("GDK_WIN32_GL_FULLSCREEN_WORKAROUND"))
+        {
+          extra_styles |= WS_BORDER;
+          workaround_padding = 1;
+          GDK_NOTE (MISC, g_print ("GL fullscreen workaround enabled for window [%p]\n",
+                                   GDK_WINDOW_HWND (window)));
+        }
+
       SetWindowLong (GDK_WINDOW_HWND (window), GWL_STYLE,
-                     (fi->style & ~WS_OVERLAPPEDWINDOW) | WS_POPUP);
+                     (fi->style & ~WS_OVERLAPPEDWINDOW) | extra_styles);
 
       API_CALL (SetWindowPos, (GDK_WINDOW_HWND (window), HWND_TOP,
-                x, y, width, height,
-                SWP_NOCOPYBITS | SWP_SHOWWINDOW | SWP_NOOWNERZORDER));
+                               x - workaround_padding,
+                               y - workaround_padding,
+                               width + (workaround_padding * 2),
+                               height + (workaround_padding * 2),
+                               SWP_NOCOPYBITS | SWP_SHOWWINDOW | SWP_NOOWNERZORDER));
     }
 }