Make construction of unitialized QTransform/QMatrix a no-op.

These constructors are useful when you have to create a temporary
uninitialized QTransform/QMatrix and later initialize it to something
else.

Done with Lars.

Reviewed-by: samuel

6 files changed, 21 insertions, 0 deletions

diff --git a/doc/src/qnamespace.qdoc b/doc/src/qnamespace.qdoc
index d46236f..8a24764 100644
--- a/doc/src/qnamespace.qdoc
+++ b/doc/src/qnamespace.qdoc
@@ -2685,3 +2685,9 @@
   \value Round 	   Like Repeat, but scales the images down to ensure that
   the last image is not cropped.
 */
+
+/*!
+    \enum Uninitialized
+    \internal
+*/
+
diff --git a/src/corelib/global/qnamespace.h b/src/corelib/global/qnamespace.h
index 46ac40b..398cd48 100644
--- a/src/corelib/global/qnamespace.h
+++ b/src/corelib/global/qnamespace.h
@@ -1542,6 +1542,10 @@ public:
         BottomLeftSection,
         TitleBarArea    // For move
     };
+
+    enum Uninitialized {
+        Uninitialized
+    };
 }
 #ifdef Q_MOC_RUN
  ;
diff --git a/src/gui/painting/qmatrix.cpp b/src/gui/painting/qmatrix.cpp
index 7c50b80..62addd3 100644
--- a/src/gui/painting/qmatrix.cpp
+++ b/src/gui/painting/qmatrix.cpp
@@ -197,6 +197,10 @@ QT_BEGIN_NAMESPACE
 /*****************************************************************************
   QMatrix member functions
  *****************************************************************************/
+/*!
+    \fn QMatrix::QMatrix(Qt::Uninitialized)
+    \internal
+*/
 
 /*!
     Constructs an identity matrix.
diff --git a/src/gui/painting/qmatrix.h b/src/gui/painting/qmatrix.h
index e28c950..b2e5d70 100644
--- a/src/gui/painting/qmatrix.h
+++ b/src/gui/painting/qmatrix.h
@@ -61,6 +61,7 @@ class QVariant;
 class Q_GUI_EXPORT QMatrix // 2D transform matrix
 {
 public:
+    inline explicit QMatrix(enum Qt::Uninitialized) {}
     QMatrix();
     QMatrix(qreal m11, qreal m12, qreal m21, qreal m22,
             qreal dx, qreal dy);
diff --git a/src/gui/painting/qtransform.cpp b/src/gui/painting/qtransform.cpp
index 5b1ae07..85adb27 100644
--- a/src/gui/painting/qtransform.cpp
+++ b/src/gui/painting/qtransform.cpp
@@ -232,6 +232,11 @@ QT_BEGIN_NAMESPACE
 */
 
 /*!
+    \fn QTransform::QTransform(Qt::Uninitialized)
+    \internal
+*/
+
+/*!
     Constructs an identity matrix.
 
     All elements are set to zero except \c m11 and \c m22 (specifying
diff --git a/src/gui/painting/qtransform.h b/src/gui/painting/qtransform.h
index bb04f7b..f99b0e7 100644
--- a/src/gui/painting/qtransform.h
+++ b/src/gui/painting/qtransform.h
@@ -71,6 +71,7 @@ public:
         TxProject   = 0x10
     };
 
+    inline explicit QTransform(enum Qt::Uninitialized) : affine(Qt::Uninitialized) {}
     QTransform();
     QTransform(qreal h11, qreal h12, qreal h13,
                qreal h21, qreal h22, qreal h23,