Merge branch '4.7' of scm.dev.nokia.troll.no:qt/oslo-staging-2 into 4.7-integration

* '4.7' of scm.dev.nokia.troll.no:qt/oslo-staging-2: (22 commits)
  ActiveQt: also make the designer plugin for qaxwidget build in the opensource versions
  Fix compilation
  Code cleaning with the merge request 2286
  Fix a pending issue with the merge request 2286
  Doc: fix description of the expected behavior for QGraphicsItem::cursor
  Fixed the build error in qtconfig
  Resolved a little code style issue in qtconfig
  Renamed controls in qtconfig's MainWindow
  Removed inheritance from UI file in qtconfig's MainWindow
  Fixed a bug and resolved some translation issues in qtconfig
  Fixed some problems in qtconfig's PreviewWidget
  Removed the inheritance from ui file in qtconfig's PaletteEditorAdvanced
  Replaced the unnecessary include with declaration
  Resolved some code style issues and fixed the broken copyright year
  Finally removed the qtconfig dependency from qt3support
  Modified previewwidget's ui file in qtconfig
  Fixed some code style issues in qtconfig
  Refactored the MainWindow in qtconfig
  Refactored PaletteEditorAdvanced in qtconfig
  Removed more legacy code from qtconfig and fixed codestyle issues
  ...

2 files changed, 59 insertions, 19 deletions

diff --git a/src/gui/graphicsview/qgraphicsitem.cpp b/src/gui/graphicsview/qgraphicsitem.cpp
index fc44a44..60cd020 100644
--- a/src/gui/graphicsview/qgraphicsitem.cpp
+++ b/src/gui/graphicsview/qgraphicsitem.cpp
@@ -2125,7 +2125,7 @@ void QGraphicsItem::setToolTip(const QString &toolTip)
 
     \snippet doc/src/snippets/code/src_gui_graphicsview_qgraphicsitem.cpp 2
 
-    If no cursor has been set, the parent's cursor is used.
+    If no cursor has been set, the cursor of the item beneath is used.
 
     \sa setCursor(), hasCursor(), unsetCursor(), QWidget::cursor,
     QApplication::overrideCursor()
diff --git a/src/gui/graphicsview/qgraphicsscene.cpp b/src/gui/graphicsview/qgraphicsscene.cpp
index e58b93c..a0015dc 100644
--- a/src/gui/graphicsview/qgraphicsscene.cpp
+++ b/src/gui/graphicsview/qgraphicsscene.cpp
@@ -4362,6 +4362,50 @@ static void _q_paintIntoCache(QPixmap *pix, QGraphicsItem *item, const QRegion &
     }
 }
 
+// Copied from qpaintengine_vg.cpp
+// Returns true for 90, 180, and 270 degree rotations.
+static inline bool transformIsSimple(const QTransform& transform)
+{
+    QTransform::TransformationType type = transform.type();
+    if (type == QTransform::TxNone || type == QTransform::TxTranslate) {
+        return true;
+    } else if (type == QTransform::TxScale) {
+        // Check for 0 and 180 degree rotations.
+        // (0 might happen after 4 rotations of 90 degrees).
+        qreal m11 = transform.m11();
+        qreal m12 = transform.m12();
+        qreal m21 = transform.m21();
+        qreal m22 = transform.m22();
+        if (m12 == 0.0f && m21 == 0.0f) {
+            if (m11 == 1.0f && m22 == 1.0f)
+                return true; // 0 degrees
+            else if (m11 == -1.0f && m22 == -1.0f)
+                return true; // 180 degrees.
+            if(m11 == 1.0f && m22 == -1.0f)
+                return true; // 0 degrees inverted y.
+            else if(m11 == -1.0f && m22 == 1.0f)
+                return true; // 180 degrees inverted y.
+        }
+    } else if (type == QTransform::TxRotate) {
+        // Check for 90, and 270 degree rotations.
+        qreal m11 = transform.m11();
+        qreal m12 = transform.m12();
+        qreal m21 = transform.m21();
+        qreal m22 = transform.m22();
+        if (m11 == 0.0f && m22 == 0.0f) {
+            if (m12 == 1.0f && m21 == -1.0f)
+                return true; // 90 degrees.
+            else if (m12 == -1.0f && m21 == 1.0f)
+                return true; // 270 degrees.
+            else if (m12 == -1.0f && m21 == -1.0f)
+                return true; // 90 degrees inverted y.
+            else if (m12 == 1.0f && m21 == 1.0f)
+                return true; // 270 degrees inverted y.
+        }
+    }
+    return false;
+}
+
 /*!
     \internal
 
@@ -4530,32 +4574,28 @@ void QGraphicsScenePrivate::drawItemHelper(QGraphicsItem *item, QPainter *painte
         if (invertable)
             diff *= painter->worldTransform();
         deviceData->lastTransform = painter->worldTransform();
-        if (!invertable
-            || diff.type() > QTransform::TxTranslate
-            || painter->worldTransform().type() > QTransform::TxScale) {
+        bool allowPartialCacheExposure = false;
+        bool simpleTransform = invertable && diff.type() <= QTransform::TxTranslate
+                               && transformIsSimple(painter->worldTransform());
+        if (!simpleTransform) {
             pixModified = true;
             itemCache->allExposed = true;
             itemCache->exposed.clear();
+            deviceData->cacheIndent = QPoint();
             pix = QPixmap();
+        } else {
+            allowPartialCacheExposure = deviceData->cacheIndent != QPoint();
         }
 
-        // ### This is a pretty bad way to determine when to start partial
-        // exposure for DeviceCoordinateCache but it's the least intrusive
-        // approach for now.
-#if 0
-        // Only if the device rect isn't fully contained.
-        bool allowPartialCacheExposure = !viewRect.contains(deviceRect);
-#else
-        // Only if deviceRect is 20% taller or wider than the desktop.
-        bool allowPartialCacheExposure = false;
-        if (widget) {
-            QRect desktopRect = QApplication::desktop()->availableGeometry(widget);
-            allowPartialCacheExposure = (desktopRect.width() * 1.2 < deviceRect.width()
-                                         || desktopRect.height() * 1.2 < deviceRect.height());
+        // Allow partial cache exposure if the device rect isn't fully contained and
+        // deviceRect is 20% taller or wider than the viewRect.
+        if (!allowPartialCacheExposure && !viewRect.contains(deviceRect)) {
+            allowPartialCacheExposure = (viewRect.width() * 1.2 < deviceRect.width())
+                                         || (viewRect.height() * 1.2 < deviceRect.height());
         }
-#endif
+
         QRegion scrollExposure;
-        if (deviceData->cacheIndent != QPoint() || allowPartialCacheExposure) {
+        if (allowPartialCacheExposure) {
             // Part of pixmap is drawn. Either device contains viewrect (big
             // item covers whole screen) or parts of device are outside the
             // viewport. In either case the device rect must be the intersect