[PATCH 1/1] winex11.drv: Limit fullscreen visible rects to the virtual screen rect.

[Zhiyi Zhang]

From: Zhiyi Zhang

Fix a regression from 31fda1f4, which allowed the visible rect to be larger than the monitor rect.
After 31fda1f4, CHRONO TRIGGER (613830) sets a window rect slightly larger than the monitor rect and
will change the window rect to the rect it previously set if the game detects a different window rect.
Adding __NET_WM_STATE_FULLSCREEN will cause WMs to move the window to cover exactly the monitor rect.
So the window rect will be repeatedly changed by the WM and the game, causing a flickering effect. Limit
fullscreen visible rects to the virtual screen rect so that the visible rects in winex11.drv are of
the same size as the monitor rect. Thus, adding __NET_WM_STATE_FULLSCREEN won't trigger a size change.
---
 dlls/winex11.drv/window.c | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/dlls/winex11.drv/window.c b/dlls/winex11.drv/window.c
index b9055791a60..a22bf699169 100644
--- a/dlls/winex11.drv/window.c
+++ b/dlls/winex11.drv/window.c
@@ -3158,8 +3158,9 @@ void X11DRV_WindowPosChanged( HWND hwnd, HWND insert_after, HWND owner_hint, UIN
 {
     struct x11drv_win_data *data;
     UINT new_style = NtUserGetWindowLongW( hwnd, GWL_STYLE ), old_style;
-    struct window_rects old_rects;
+    struct window_rects old_rects, tmp_rects;
     BOOL was_fullscreen, activate = !(swp_flags & SWP_NOACTIVATE);
+    RECT virtual;

if (!(data = get_win_data( hwnd ))) return;
     if (is_window_managed( hwnd, swp_flags, fullscreen )) window_set_managed( data, TRUE );
@@ -3169,6 +3170,20 @@ void X11DRV_WindowPosChanged( HWND hwnd, HWND insert_after, HWND owner_hint, UIN
     if (data->desired_state.wm_state == IconicState) old_style |= WS_MINIMIZE;
     if (data->desired_state.net_wm_state & (1 << NET_WM_STATE_MAXIMIZED)) old_style |= WS_MAXIMIZE;

+    /* If the visible rect is fullscreen on any one of the monitors, limit the visible rect to the
+     * virtual screen rect. This is needed because adding __NET_WM_STATE_FULLSCREEN will make WMs
+     * move the window to cover exactly the monitor rect. If the application sets a visible rect
+     * slightly larger than the monitor rect and insists on changing to the rect that it previously
+     * set when the rect is changed by the WM, then the window rect will be repeatedly changed by
+     * the WM and the application, causing a flickering effect */
+    if (fullscreen)
+    {
+        virtual = NtUserGetVirtualScreenRect( MDT_RAW_DPI );
+        tmp_rects = *new_rects;
+        intersect_rect( &tmp_rects.visible, &tmp_rects.visible, &virtual );
+        new_rects = &tmp_rects;
+    }
+
     old_rects = data->rects;
     was_fullscreen = data->is_fullscreen;
     data->rects = *new_rects;