Improved support for DPI on Mac and Vista/7

This significantly improves the support for
higher DPI-values on these platforms by
ensuring that common pixelmetrics are
scaled accordingly. In addition we mark all
Qt apps as DPI-aware on Windows 7 by calling
SetProcessDPIAware. We also changed the
way we draw pixmaps on the mac paintengine
when using dpi scaling > 1 to ensure smooth
pixmap scaling.

Reviewed-by: nrc
Task-id: 242417

1 files changed, 9 insertions, 0 deletions

diff --git a/src/gui/kernel/qapplication_win.cpp b/src/gui/kernel/qapplication_win.cpp
index 324fac7..a690ffd 100644
--- a/src/gui/kernel/qapplication_win.cpp
+++ b/src/gui/kernel/qapplication_win.cpp
@@ -720,7 +720,11 @@ void QApplicationPrivate::initializeWidgetPaletteHash()
 typedef BOOL (WINAPI *PtrUpdateLayeredWindow)(HWND hwnd, HDC hdcDst, const POINT *pptDst,
     const SIZE *psize, HDC hdcSrc, const POINT *pptSrc, COLORREF crKey,
     const Q_BLENDFUNCTION *pblend, DWORD dwflags);
+
+typedef BOOL (WINAPI *PtrSetProcessDPIAware) (VOID);
+
 static PtrUpdateLayeredWindow ptrUpdateLayeredWindow = 0;
+static PtrSetProcessDPIAware ptrSetProcessDPIAware = 0;
 
 static BOOL WINAPI qt_updateLayeredWindowIndirect(HWND hwnd, const Q_UPDATELAYEREDWINDOWINFO *info)
 {
@@ -846,6 +850,11 @@ void qt_init(QApplicationPrivate *priv, int)
 
     if (ptrUpdateLayeredWindow && !ptrUpdateLayeredWindowIndirect)
         ptrUpdateLayeredWindowIndirect = qt_updateLayeredWindowIndirect;
+
+    // Notify Vista and Windows 7 that we support highter DPI settings
+    if (ptrSetProcessDPIAware = (PtrSetProcessDPIAware)
+        QLibrary::resolve(QLatin1String("user32"), "SetProcessDPIAware"))
+    ptrSetProcessDPIAware();
 #endif
 }