Implement new transformation handling for graphics items.

The idea of having separate rotationX/Y/Z, shearX/Y, etc.
methods in QGraphicsItem turned out to be not giving us
the flexibility we need and wanted.

The new code now implements a different scheme, where we
keep simple rotate (around z-axis), scale and
transformOriginPoint methods, but remove the other ones.

Instead we now have an additional list of QGraphicsTransform
object. QGraphicsTransform is an abstract class that inherits
QObject. Several specializations are provided and can be
used to transform (and through property bindings animate)
the item.

Reviewed-By: Andreas

1 files changed, 99 insertions, 240 deletions

diff --git a/src/gui/graphicsview/qgraphicsitem.cpp b/src/gui/graphicsview/qgraphicsitem.cpp
index 06f26a1..6770206 100644
--- a/src/gui/graphicsview/qgraphicsitem.cpp
+++ b/src/gui/graphicsview/qgraphicsitem.cpp
@@ -1197,6 +1197,13 @@ QGraphicsItem::~QGraphicsItem()
     else
         d_ptr->setParentItemHelper(0);
 
+    if (d_ptr->transformData) {
+        for(int i = 0; i < d_ptr->transformData->graphicsTransforms.size(); ++i) {
+            QGraphicsTransform *t = d_ptr->transformData->graphicsTransforms.at(i);
+            static_cast<QGraphicsTransformPrivate *>(t->d_ptr)->item = 0;
+            delete t;
+        }
+    }
     delete d_ptr->transformData;
     delete d_ptr;
 
@@ -2980,94 +2987,19 @@ QTransform QGraphicsItem::transform() const
 /*!
     \since 4.6
 
-    Returns the rotation around the X axis.
-
-    The default is 0
-
-    \warning The value doesn't take in account any rotation set with
-    the setTransform() method.
-
-    \sa setXRotation(), {Transformations}
-*/
-qreal QGraphicsItem::xRotation() const
-{
-    if (!d_ptr->transformData)
-        return 0;
-    return d_ptr->transformData->xRotation;
-}
-
-/*!
-    \since 4.6
-
-    Sets the rotation around the X axis to \a angle degrees.
-
-    \warning The value doesn't take in account any rotation set with the setTransform() method.
-
-    \sa xRotation(), setTransformOrigin(), {Transformations}
-*/
-void QGraphicsItem::setXRotation(qreal angle)
-{
-    prepareGeometryChange();
-    if (!d_ptr->transformData)
-        d_ptr->transformData = new QGraphicsItemPrivate::TransformData;
-    d_ptr->transformData->xRotation = angle;
-    d_ptr->transformData->onlyTransform = false;
-    d_ptr->dirtySceneTransform = 1;
-}
-
-/*!
-    \since 4.6
-
-    Returns the rotation around the Y axis.
-
-    The default is 0
-
-    \warning The value doesn't take in account any rotation set with the setTransform() method.
-
-    \sa setYRotation(), {Transformations}
-*/
-qreal QGraphicsItem::yRotation() const
-{
-    if (!d_ptr->transformData)
-        return 0;
-    return d_ptr->transformData->yRotation;
-}
-
-/*!
-    \since 4.6
-
-    Sets the rotation around the Y axis to \a angle degrees.
-
-    \warning The value doesn't take in account any rotation set with the setTransform() method.
-
-    \sa yRotation(), setTransformOrigin() {Transformations}
-*/
-void QGraphicsItem::setYRotation(qreal angle)
-{
-    prepareGeometryChange();
-    if (!d_ptr->transformData)
-        d_ptr->transformData = new QGraphicsItemPrivate::TransformData;
-    d_ptr->transformData->yRotation = angle;
-    d_ptr->transformData->onlyTransform = false;
-    d_ptr->dirtySceneTransform = 1;
-}
-
-/*!
-    \since 4.6
-
     Returns the rotation around the Z axis.
 
     The default is 0
 
     \warning The value doesn't take in account any rotation set with the setTransform() method.
 
-    \sa setZRotation(), {Transformations}
+    \sa setRotation(), {Transformations}
 */
-qreal QGraphicsItem::zRotation() const
+qreal QGraphicsItem::rotation() const
 {
     if (!d_ptr->transformData)
         return 0;
-    return d_ptr->transformData->zRotation;
+    return d_ptr->transformData->rotation;
 }
 
 /*!
@@ -3077,224 +3009,107 @@ qreal QGraphicsItem::zRotation() const
 
     \warning The value doesn't take in account any rotation set with the setTransform() method.
 
-    \sa zRotation(), setTransformOrigin(), {Transformations}
+    \sa rotation(), setTransformOriginPoint(), {Transformations}
 */
-void QGraphicsItem::setZRotation(qreal angle)
+void QGraphicsItem::setRotation(qreal angle)
 {
     prepareGeometryChange();
     if (!d_ptr->transformData)
         d_ptr->transformData = new QGraphicsItemPrivate::TransformData;
-    d_ptr->transformData->zRotation = angle;
+    d_ptr->transformData->rotation = angle;
     d_ptr->transformData->onlyTransform = false;
     d_ptr->dirtySceneTransform = 1;
-}
-
-/*!
-    \since 4.6
 
-    This convenience function set the rotation angles around the 3 axes
-    to \a x, \a y and \a z.
-
-    \sa setXRotation(), setYRotation(), setZRotation(), {Transformations}
-*/
-void QGraphicsItem::setRotation(qreal x, qreal y, qreal z)
-{
-    prepareGeometryChange();
-    if (!d_ptr->transformData)
-        d_ptr->transformData = new QGraphicsItemPrivate::TransformData;
-    d_ptr->transformData->xRotation = x;
-    d_ptr->transformData->yRotation = y;
-    d_ptr->transformData->zRotation = z;
-    d_ptr->transformData->onlyTransform = false;
-    d_ptr->dirtySceneTransform = 1;
+    if (d_ptr->isObject)
+        emit static_cast<QGraphicsObject *>(this)->rotationChanged();
 }
 
 /*!
     \since 4.6
 
-    Returns the scale factor on the X axis.
+    Returns the scale factor of the item.
 
     The default is 1
 
     \warning The value doesn't take in account any scaling set with the setTransform() method.
 
-    \sa setXScale(), {Transformations}
+    \sa setScale(), {Transformations}
 */
-qreal QGraphicsItem::xScale() const
+qreal QGraphicsItem::scale() const
 {
     if (!d_ptr->transformData)
-        return 1;
-    return d_ptr->transformData->xScale;
+        return 1.;
+    return d_ptr->transformData->scale;
 }
 
 /*!
     \since 4.6
 
-    Sets the scale factor on the X axis to \a factor.
+    Sets the scale factor of the item to \a factor.
 
     \warning The value doesn't take in account any scaling set with the setTransform() method.
 
-    \sa xScale(), setTransformOrigin(), {Transformations}
+    \sa scale(), setTransformOriginPoint(), {Transformations}
 */
-void QGraphicsItem::setXScale(qreal factor)
+void QGraphicsItem::setScale(qreal factor)
 {
     prepareGeometryChange();
     if (!d_ptr->transformData)
         d_ptr->transformData = new QGraphicsItemPrivate::TransformData;
-    d_ptr->transformData->xScale = factor;
+    d_ptr->transformData->scale = factor;
     d_ptr->transformData->onlyTransform = false;
     d_ptr->dirtySceneTransform = 1;
-}
-
-/*!
-    \since 4.6
-
-    Returns the scale factor on the Y axis.
-
-    The default is 1
-
-    \warning The value doesn't take in account any scaling set with the setTransform() method.
-
-    \sa setYScale(), {Transformations}
-*/
-qreal QGraphicsItem::yScale() const
-{
-    if (!d_ptr->transformData)
-        return 1;
-    return d_ptr->transformData->yScale;
-}
-
-/*!
-    \since 4.6
-
-    Sets the scale factor on the Y axis to \a factor.
 
-    \warning The value doesn't take in account any scaling set with the setTransform() method.
-
-    \sa yScale(), setTransformOrigin(), {Transformations}
-*/
-void QGraphicsItem::setYScale(qreal factor)
-{
-    prepareGeometryChange();
-    if (!d_ptr->transformData)
-        d_ptr->transformData = new QGraphicsItemPrivate::TransformData;
-    d_ptr->transformData->yScale = factor;
-    d_ptr->transformData->onlyTransform = false;
-    d_ptr->dirtySceneTransform = 1;
+    if (d_ptr->isObject)
+        emit static_cast<QGraphicsObject *>(this)->scaleChanged();
 }
 
-/*!
-    \since 4.6
-
-    This convenience function set the scaling factors on X and Y axis to \a sx and \a sy.
-
-    \warning The value doesn't take in account any scaling set with the setTransform() method.
-
-    \sa setXScale(), setYScale(), {Transformations}
-*/
-void QGraphicsItem::setScale(qreal sx, qreal sy)
-{
-    prepareGeometryChange();
-    if (!d_ptr->transformData)
-        d_ptr->transformData = new QGraphicsItemPrivate::TransformData;
-    d_ptr->transformData->xScale = sx;
-    d_ptr->transformData->yScale = sy;
-    d_ptr->transformData->onlyTransform = false;
-    d_ptr->dirtySceneTransform = 1;
-}
 
 /*!
     \since 4.6
 
-    Returns the horizontal shear.
-
-    The default is 0
-
-    \warning The value doesn't take in account any shearing set with the setTransform() method.
+    returns list of graphics transformations on the item.
 
-    \sa setHorizontalShear(), {Transformations}
+    \sa scale(), setTransformOriginPoint(), {Transformations}
 */
-qreal QGraphicsItem::horizontalShear() const
+QList<QGraphicsTransform *> QGraphicsItem::transformations() const
 {
     if (!d_ptr->transformData)
-        return 0;
-    return d_ptr->transformData->horizontalShear;
+        return QList<QGraphicsTransform *>();
+    return d_ptr->transformData->graphicsTransforms;
 }
 
 /*!
     \since 4.6
 
-    Sets the horizontal shear to \a shear.
-
-    \warning The value doesn't take in account any shearing set with the setTransform() method.
+    Sets a list of graphics transformations on the item to \a transformations.
 
-    \sa horizontalShear(), {Transformations}
+    \sa scale(), setTransformOriginPoint(), {Transformations}
 */
-void QGraphicsItem::setHorizontalShear(qreal shear)
+void QGraphicsItem::setTransformations(const QList<QGraphicsTransform *> &transformations)
 {
     prepareGeometryChange();
     if (!d_ptr->transformData)
         d_ptr->transformData = new QGraphicsItemPrivate::TransformData;
-    d_ptr->transformData->horizontalShear = shear;
+    d_ptr->transformData->graphicsTransforms = transformations;
+    for (int i = 0; i < transformations.size(); ++i)
+        transformations.at(i)->d_func()->setItem(this);
     d_ptr->transformData->onlyTransform = false;
     d_ptr->dirtySceneTransform = 1;
 }
 
-/*!
-    \since 4.6
-
-    Returns the vertical shear.
-
-    The default is 0
-
-    \warning The value doesn't take in account any shearing set with the setTransform() method.
 
-    \sa setHorizontalShear(), {Transformations}
-*/
-qreal QGraphicsItem::verticalShear() const
+void QGraphicsItemPrivate::appendGraphicsTransform(QGraphicsTransform *t)
 {
-    if (!d_ptr->transformData)
-        return 0;
-    return d_ptr->transformData->verticalShear;
-}
+    if (!transformData)
+        transformData = new QGraphicsItemPrivate::TransformData;
+    if (!transformData->graphicsTransforms.contains(t))
+        transformData->graphicsTransforms.append(t);
 
-/*!
-    \since 4.6
-
-    Sets the vertical shear to \a shear.
-
-    \warning The value doesn't take in account any shearing set with the setTransform() method.
-
-    \sa verticalShear(), {Transformations}
-*/
-void QGraphicsItem::setVerticalShear(qreal shear)
-{
-    prepareGeometryChange();
-    if (!d_ptr->transformData)
-        d_ptr->transformData = new QGraphicsItemPrivate::TransformData;
-    d_ptr->transformData->verticalShear = shear;
-    d_ptr->transformData->onlyTransform = false;
-    d_ptr->dirtySceneTransform = 1;
-}
-
-/*!
-    \since 4.6
-
-    This convenience function sets the horizontal shear to \a sh and the vertical shear to \a sv.
-
-    \warning The value doesn't take in account any shearing set with the setTransform() method.
-
-    \sa setHorizontalShear(), setVerticalShear()
-*/
-void QGraphicsItem::setShear(qreal sh, qreal sv)
-{
-    prepareGeometryChange();
-    if (!d_ptr->transformData)
-        d_ptr->transformData = new QGraphicsItemPrivate::TransformData;
-    d_ptr->transformData->horizontalShear = sh;
-    d_ptr->transformData->verticalShear = sv;
-    d_ptr->transformData->onlyTransform = false;
-    d_ptr->dirtySceneTransform = 1;
+    Q_Q(QGraphicsItem);
+    t->d_func()->setItem(q);
+    transformData->onlyTransform = false;
+    dirtySceneTransform = 1;
 }
 
 /*!
@@ -3304,9 +3119,9 @@ void QGraphicsItem::setShear(qreal sh, qreal sv)
 
     The default is QPointF(0,0).
 
-    \sa setTransformOrigin(), {Transformations}
+    \sa setTransformOriginPoint(), {Transformations}
 */
-QPointF QGraphicsItem::transformOrigin() const
+QPointF QGraphicsItem::transformOriginPoint() const
 {
     if (!d_ptr->transformData)
         return QPointF(0,0);
@@ -3318,9 +3133,9 @@ QPointF QGraphicsItem::transformOrigin() const
 
     Sets the \a origin point for the transformation in item coordinates.
 
-    \sa transformOrigin(), {Transformations}
+    \sa transformOriginPoint(), {Transformations}
 */
-void QGraphicsItem::setTransformOrigin(const QPointF &origin)
+void QGraphicsItem::setTransformOriginPoint(const QPointF &origin)
 {
     prepareGeometryChange();
     if (!d_ptr->transformData)
@@ -3332,15 +3147,15 @@ void QGraphicsItem::setTransformOrigin(const QPointF &origin)
 }
 
 /*!
-    \fn void QGraphicsItem::setTransformOrigin(qreal x, qreal y)
+    \fn void QGraphicsItem::setTransformOriginPoint(qreal x, qreal y)
 
     \since 4.6
     \overload
 
     Sets the origin point for the transformation in item coordinates.
-    This is equivalent to calling setTransformOrigin(QPointF(\a x, \a y)).
+    This is equivalent to calling setTransformOriginPoint(QPointF(\a x, \a y)).
 
-    \sa setTransformOrigin(), {Transformations}
+    \sa setTransformOriginPoint(), {Transformations}
 */
 
 
@@ -3619,7 +3434,7 @@ void QGraphicsItem::setMatrix(const QMatrix &matrix, bool combine)
 
     \warning using this function doesnt affect the value of the transformation properties
 
-    \sa transform(), setRotation(), setScale(), setShear(), setTransformOrigin(), {The Graphics View Coordinate System}, {Transformations}
+    \sa transform(), setRotation(), setScale(), setTransformOriginPoint(), {The Graphics View Coordinate System}, {Transformations}
 */
 void QGraphicsItem::setTransform(const QTransform &matrix, bool combine)
 {
@@ -3733,7 +3548,7 @@ void QGraphicsItem::shear(qreal sh, qreal sv)
 
 /*!
     \obsolete
-    Use setPos() or setTransformOrigin() instead.
+    Use setPos() or setTransformOriginPoint() instead.
 
     Translates the current item transformation by (\a dx, \a dy).
 
@@ -6857,6 +6672,41 @@ QGraphicsObject::QGraphicsObject(QGraphicsItemPrivate &dd, QGraphicsItem *parent
   \sa pos()
 */
 
+/*!
+  \property QGraphicsObject::rotation
+  This property holds the rotation of the item in degrees.
+
+  This specifies how many degrees to rotate the item around its transformOrigin.
+  The default rotation is 0 degrees (i.e. not rotated at all).
+*/
+
+/*!
+  \fn QGraphicsObject::rotationChanged()
+
+  This signal gets emitted whenever the roation of the item changes.
+*/
+
+/*!
+  \property QGraphicsObject::scale
+  This property holds the scale of the item.
+
+  A scale of less than 1 means the item will be displayed smaller than
+  normal, and a scale of greater than 1 means the item will be
+  displayed larger than normal.  A negative scale means the item will
+  be mirrored.
+
+  By default, items are displayed at a scale of 1 (i.e. at their
+  normal size).
+
+  Scaling is from the item's transformOrigin.
+*/
+
+/*!
+  \fn void QGraphicsObject::scaleChanged()
+
+  This signal is emitted when the scale of the item changes.
+*/
+
 
 /*!
   \property QGraphicsObject::enabled
@@ -6896,6 +6746,15 @@ QGraphicsObject::QGraphicsObject(QGraphicsItemPrivate &dd, QGraphicsItem *parent
   \sa visible
 */
 
+/*!
+  \property QGraphicsObject::transformOriginPoint
+  \brief the transformation origin
+
+  This property sets a specific point in the items coordiante system as the
+  origin for scale and rotation.
+
+  \sa scale, rotation, QGraphicsItem::transformOriginPoint()
+*/
 
 
 /*!