Add an extension to QPixmapCache to get rid of strings.

This commit add a new API to add/find/remove pixmaps into QPixmapCache.
This new extension is based on a key that the cache give you during
the insertion. This key is internally a int which makes all operations
in the cache much more faster that the string approach.
Auto-tests has been extended as well and a benchmark has been added to
compare both approach. I also depecrate the find method for the
string API to have a method pointer based and not reference based like
the Qt policy says.

Reviewed-by: bnilsen
Reviewed-by: andreas
Followed-deeply-by: trond

1 files changed, 4 insertions, 2 deletions

diff --git a/src/gui/graphicsview/qgraphicsitem_p.h b/src/gui/graphicsview/qgraphicsitem_p.h
index 82a48fb..820ef04 100644
--- a/src/gui/graphicsview/qgraphicsitem_p.h
+++ b/src/gui/graphicsview/qgraphicsitem_p.h
@@ -54,6 +54,7 @@
 //
 
 #include "qgraphicsitem.h"
+#include "qpixmapcache.h"
 
 #if !defined(QT_NO_GRAPHICSVIEW) || (QT_EDITION & QT_MODULE_GRAPHICSVIEW) != QT_MODULE_GRAPHICSVIEW
 
@@ -69,13 +70,14 @@ public:
     // ItemCoordinateCache only
     QRect boundingRect;
     QSize fixedSize;
-    QString key;
+    QPixmapCache::Key key;
 
     // DeviceCoordinateCache only
     struct DeviceData {
+        DeviceData() {}
         QTransform lastTransform;
         QPoint cacheIndent;
-        QString key;
+        QPixmapCache::Key key;
     };
     QMap<QPaintDevice *, DeviceData> deviceData;