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, 7 insertions, 2 deletions

diff --git a/src/gui/painting/qpaintengine_mac.cpp b/src/gui/painting/qpaintengine_mac.cpp
index 793460f..f5f1bba 100644
--- a/src/gui/painting/qpaintengine_mac.cpp
+++ b/src/gui/painting/qpaintengine_mac.cpp
@@ -1381,8 +1381,13 @@ QCoreGraphicsPaintEngine::updateRenderHints(QPainter::RenderHints hints)
 {
     Q_D(QCoreGraphicsPaintEngine);
     CGContextSetShouldAntialias(d->hd, hints & QPainter::Antialiasing);
-    CGContextSetInterpolationQuality(d->hd, (hints & QPainter::SmoothPixmapTransform) ?
-                                     kCGInterpolationHigh : kCGInterpolationNone);
+    static const CGFloat ScaleFactor = qt_mac_get_scalefactor();
+    if (ScaleFactor > 1.) {
+        CGContextSetInterpolationQuality(d->hd, kCGInterpolationHigh);
+    } else {
+        CGContextSetInterpolationQuality(d->hd, (hints & QPainter::SmoothPixmapTransform) ?
+                                         kCGInterpolationHigh : kCGInterpolationNone);
+    }
     CGContextSetShouldSmoothFonts(d->hd, hints & QPainter::TextAntialiasing);
 }