diff --git a/src/gui/image/qpixmap_x11.cpp b/src/gui/image/qpixmap_x11.cpp
index ecfe7ba35..c39307b43 100644
--- a/src/gui/image/qpixmap_x11.cpp
+++ b/src/gui/image/qpixmap_x11.cpp
@@ -418,7 +418,7 @@ void QX11PixmapData::fromImage(const QImage &img,
         return;
     }
 
-    if (uint(w) >= 32768 || uint(h) >= 32768) {
+    if (w >= 32768 || h >= 32768) {
         w = h = 0;
         is_null = true;
         return;
diff --git a/src/gui/image/qpixmapdata.cpp b/src/gui/image/qpixmapdata.cpp
index 98ebfe40f..70230251a 100644
--- a/src/gui/image/qpixmapdata.cpp
+++ b/src/gui/image/qpixmapdata.cpp
@@ -62,7 +62,7 @@ QPixmapData *QPixmapData::create(int w, int h, PixelType type)
 }
 
 
-QPixmapData::QPixmapData(PixelType pixelType, int objectId)
+QPixmapData::QPixmapData(PixelType pixelType, ClassId objectId)
     : w(0),
       h(0),
       d(0),
@@ -247,11 +247,7 @@ void QPixmapData::setSerialNumber(int serNo)
 
 QImage QPixmapData::toImage(const QRect &rect) const
 {
-    QImage image = toImage();
-    if (rect.isNull())
-        return image;
-
-    return image.copy(rect);
+    return toImage().copy(rect);
 }
 
 QImage* QPixmapData::buffer()
diff --git a/src/gui/image/qpixmapdata_p.h b/src/gui/image/qpixmapdata_p.h
index 67c8a62fa..bd9827f65 100644
--- a/src/gui/image/qpixmapdata_p.h
+++ b/src/gui/image/qpixmapdata_p.h
@@ -63,7 +63,7 @@ public:
     };
     enum ClassId { RasterClass, X11Class };
 
-    QPixmapData(PixelType pixelType, int classId);
+    QPixmapData(PixelType pixelType, ClassId classId);
     virtual ~QPixmapData();
 
     virtual QPixmapData *createCompatiblePixmapData() const;
@@ -98,7 +98,7 @@ public:
     inline int serialNumber() const { return ser_no; }
 
     inline PixelType pixelType() const { return type; }
-    inline ClassId classId() const { return static_cast<ClassId>(id); }
+    inline ClassId classId() const { return id; }
 
     virtual QImage* buffer();
 
@@ -108,19 +108,15 @@ public:
     inline int depth() const { return d; }
     inline bool isNull() const { return is_null; }
     inline qint64 cacheKey() const {
-        int classKey = id;
-        if (classKey >= 1024)
-            classKey = -(classKey >> 10);
-        return ((((qint64) classKey) << 56)
-                | (((qint64) ser_no) << 32)
-                | ((qint64) detach_no));
+        return ((static_cast<qint64>(id) << 56)
+                | (static_cast<qint64>(ser_no) << 32)
+                | (static_cast<qint64>(detach_no)));
     }
 
 
     static QPixmapData *create(int w, int h, PixelType type);
 
 protected:
-
     void setSerialNumber(int serNo);
     int w;
     int h;
@@ -136,12 +132,12 @@ private:
     int detach_no;
 
     PixelType type;
-    int id;
+    ClassId id;
     int ser_no;
 };
 
-#  define QT_XFORM_TYPE_MSBFIRST 0
-#  define QT_XFORM_TYPE_LSBFIRST 1
+#define QT_XFORM_TYPE_MSBFIRST 0
+#define QT_XFORM_TYPE_LSBFIRST 1
 extern bool qt_xForm_helper(const QTransform&, int, int, int, uchar*, int, int, int, const uchar*, int, int, int);
 
 QT_END_NAMESPACE