From 92f5c6e410fe0dbcbfa4aae708e7afd9564efb21 Mon Sep 17 00:00:00 2001
From: Alexandre Julliard <julliard@winehq.org>
Date: Thu, 23 Aug 2018 12:23:47 +0200
Subject: [PATCH] user32: Scale monitor rectangles based on DPI awareness.

Signed-off-by: Alexandre Julliard <julliard@winehq.org>
---
 dlls/user32/sysparams.c | 26 +++++++++++++++++++++++++-
 dlls/user32/win.h       |  1 +
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/dlls/user32/sysparams.c b/dlls/user32/sysparams.c
index 10f90a25262..b6679c5deba 100644
--- a/dlls/user32/sysparams.c
+++ b/dlls/user32/sysparams.c
@@ -3221,6 +3221,21 @@ UINT get_thread_dpi(void)
     }
 }
 
+/**********************************************************************
+ *              map_dpi_rect
+ */
+RECT map_dpi_rect( RECT rect, UINT dpi_from, UINT dpi_to )
+{
+    if (dpi_from && dpi_to && dpi_from != dpi_to)
+    {
+        rect.left   = MulDiv( rect.left, dpi_to, dpi_from );
+        rect.top    = MulDiv( rect.top, dpi_to, dpi_from );
+        rect.right  = MulDiv( rect.right, dpi_to, dpi_from );
+        rect.bottom = MulDiv( rect.bottom, dpi_to, dpi_from );
+    }
+    return rect;
+}
+
 /**********************************************************************
  *              SetProcessDpiAwarenessContext   (USER32.@)
  */
@@ -3586,13 +3601,22 @@ BOOL WINAPI GetMonitorInfoA( HMONITOR monitor, LPMONITORINFO info )
 BOOL WINAPI GetMonitorInfoW( HMONITOR monitor, LPMONITORINFO info )
 {
     BOOL ret;
+    UINT dpi_from, dpi_to;
 
     if (info->cbSize != sizeof(MONITORINFOEXW) && info->cbSize != sizeof(MONITORINFO)) return FALSE;
 
     ret = USER_Driver->pGetMonitorInfo( monitor, info );
     if (ret)
+    {
+        if ((dpi_to = get_thread_dpi()))
+        {
+            dpi_from = get_monitor_dpi( monitor );
+            info->rcMonitor = map_dpi_rect( info->rcMonitor, dpi_from, dpi_to );
+            info->rcWork = map_dpi_rect( info->rcWork, dpi_from, dpi_to );
+        }
         TRACE( "flags %04x, monitor %s, work %s\n", info->dwFlags,
                wine_dbgstr_rect(&info->rcMonitor), wine_dbgstr_rect(&info->rcWork));
+    }
     return ret;
 }
 
@@ -3634,7 +3658,7 @@ __ASM_GLOBAL_FUNC( enum_mon_callback_wrapper,
 static BOOL CALLBACK enum_mon_callback( HMONITOR monitor, HDC hdc, LPRECT rect, LPARAM lp )
 {
     struct enum_mon_data *data = (struct enum_mon_data *)lp;
-    RECT monrect = *rect;
+    RECT monrect = map_dpi_rect( *rect, get_monitor_dpi( monitor ), get_thread_dpi() );
 
     OffsetRect( &monrect, -data->origin.x, -data->origin.y );
     if (!IntersectRect( &monrect, &monrect, &data->limit )) return TRUE;
diff --git a/dlls/user32/win.h b/dlls/user32/win.h
index f9e11ffab89..226e3e9c00a 100644
--- a/dlls/user32/win.h
+++ b/dlls/user32/win.h
@@ -131,6 +131,7 @@ extern void WINPOS_SysCommandSizeMove( HWND hwnd, WPARAM wParam ) DECLSPEC_HIDDE
 extern UINT get_monitor_dpi( HMONITOR monitor ) DECLSPEC_HIDDEN;
 extern UINT get_win_monitor_dpi( HWND hwnd ) DECLSPEC_HIDDEN;
 extern UINT get_thread_dpi(void) DECLSPEC_HIDDEN;
+extern RECT map_dpi_rect( RECT rect, UINT dpi_from, UINT dpi_to ) DECLSPEC_HIDDEN;
 extern BOOL set_window_pos( HWND hwnd, HWND insert_after, UINT swp_flags,
                             const RECT *window_rect, const RECT *client_rect,
                             const RECT *valid_rects ) DECLSPEC_HIDDEN;