Windows QPA: Use new EnableNonClientDpiScaling() for Windows decoration

Use newly introduced EnableNonClientDpiScaling() function to fix
the decoration having the wrong size in multimonitor setups with
per-monitor DPI awareness.

Task-number: QTBUG-53255
Change-Id: Ic6e2f2a92f790259107d2a0837b96177cf3adb5f
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

1 files changed, 7 insertions, 0 deletions

diff --git a/src/plugins/platforms/windows/qwindowscontext.h b/src/plugins/platforms/windows/qwindowscontext.h
index 41405f8efc..43fde03fa3 100644
--- a/src/plugins/platforms/windows/qwindowscontext.h
+++ b/src/plugins/platforms/windows/qwindowscontext.h
@@ -94,6 +94,9 @@ struct QWindowsUser32DLL
     typedef BOOL (WINAPI *RemoveClipboardFormatListener)(HWND);
     typedef BOOL (WINAPI *GetDisplayAutoRotationPreferences)(DWORD *);
     typedef BOOL (WINAPI *SetDisplayAutoRotationPreferences)(DWORD);
+    typedef BOOL (WINAPI *EnableNonClientDpiScaling)(HWND);
+    typedef int  (WINAPI *GetWindowDpiAwarenessContext)(HWND);
+    typedef int  (WINAPI *GetAwarenessFromDpiAwarenessContext)(int);
 
     // Touch functions from Windows 7 onwards (also for use with Q_CC_MSVC).
     IsTouchWindow isTouchWindow;
@@ -113,6 +116,10 @@ struct QWindowsUser32DLL
     // Rotation API
     GetDisplayAutoRotationPreferences getDisplayAutoRotationPreferences;
     SetDisplayAutoRotationPreferences setDisplayAutoRotationPreferences;
+
+    EnableNonClientDpiScaling enableNonClientDpiScaling;
+    GetWindowDpiAwarenessContext getWindowDpiAwarenessContext;
+    GetAwarenessFromDpiAwarenessContext getAwarenessFromDpiAwarenessContext;
 };
 
 // Shell scaling library (Windows 8.1 onwards)