simplify and cleanup handling of transformations in QGraphicsItem

Removed some experimental code to handle scaling and rotating around
different axis. It cuased setTransform and transform not to behave
symmetrically and caused some performance regressions.

Additionally moved the QTransform out of the (relatively slow) extra
list and made it a pointer in QGraphicsItemPrivate.

Reviewed-by: Andreas

1 files changed, 16 insertions, 413 deletions

diff --git a/src/gui/graphicsview/qgraphicsitem.cpp b/src/gui/graphicsview/qgraphicsitem.cpp
index ec6b35b..14658cf 100644
--- a/src/gui/graphicsview/qgraphicsitem.cpp
+++ b/src/gui/graphicsview/qgraphicsitem.cpp
@@ -1102,6 +1102,9 @@ QGraphicsItem::~QGraphicsItem()
     if (d_ptr->scene)
         d_ptr->scene->d_func()->_q_removeItemLater(this);
 
+    if (d_ptr->transform)
+        delete d_ptr->transform;
+
     delete d_ptr;
 
     qt_dataStore()->data.remove(this);
@@ -2627,403 +2630,9 @@ QMatrix QGraphicsItem::matrix() const
 */
 QTransform QGraphicsItem::transform() const
 {
-    if (!d_ptr->hasTransform)
+    if (!d_ptr->hasTransform || !d_ptr->transform)
         return QTransform();
-    if (d_ptr->hasDecomposedTransform && d_ptr->dirtyTransform) {
-        QGraphicsItemPrivate::DecomposedTransform *decomposed = d_ptr->decomposedTransform();
-        QTransform x;
-        decomposed->generateTransform(&x);
-        QVariant v(x);
-        d_ptr->setExtra(QGraphicsItemPrivate::ExtraTransform, v);
-        d_ptr->dirtyTransform = 0;
-        const_cast<QGraphicsItem *>(this)->itemChange(ItemTransformHasChanged, v);
-        return x;
-    }
-    return qVariantValue<QTransform>(d_ptr->extra(QGraphicsItemPrivate::ExtraTransform));
-}
-
-/*!
-    \since 4.6
-
-    Returns the rotation around the X axis.
-
-    The default is 0
-
-    \warning setting this property is conflicting with calling setTransform.
-    If a transform has been set, this function return the default value.
-
-    \sa setXRotation(), {Transformations}
-*/
-qreal QGraphicsItem::xRotation() const
-{
-    return d_ptr->decomposedTransform()->xRotation;
-}
-
-/*!
-    \since 4.6
-
-    Sets the rotation around the X axis to \a angle degrees.
-
-    \warning setting this property is conflicting with calling setTransform.
-    If a transform has been set, it will be overwritten.
-
-    \sa xRotation(), {Transformations}
-*/
-void QGraphicsItem::setXRotation(qreal angle)
-{
-    if (!d_ptr->dirtyTransform) {
-        d_ptr->fullUpdateHelper(true);
-        prepareGeometryChange();
-    }
-    QGraphicsItemPrivate::DecomposedTransform *decomposed = d_ptr->decomposedTransform();
-    decomposed->xRotation = angle;
-    if (!d_ptr->dirtyTransform)
-        d_ptr->invalidateSceneTransformCache();
-    d_ptr->dirtyTransform = 1;
-    d_ptr->hasTransform = 1;
-}
-
-/*!
-    \since 4.6
-
-    Returns the rotation around the Y axis.
-
-    The default is 0
-
-    \warning setting this property is conflicting with calling setTransform.
-    If a transform has been set, this function return the default value.
-
-    \sa setYRotation(), {Transformations}
-*/
-qreal QGraphicsItem::yRotation() const
-{
-    return d_ptr->decomposedTransform()->yRotation;
-}
-
-/*!
-    \since 4.6
-
-    Sets the rotation around the Y axis to \a angle degrees.
-
-    \warning setting this property is conflicting with calling setTransform.
-    If a transform has been set, it will be overwritten.
-
-    \sa yRotation(), {Transformations}
-*/
-void QGraphicsItem::setYRotation(qreal angle)
-{
-    if (!d_ptr->dirtyTransform) {
-        d_ptr->fullUpdateHelper(true);
-        prepareGeometryChange();
-    }
-    QGraphicsItemPrivate::DecomposedTransform *decomposed = d_ptr->decomposedTransform();
-    decomposed->yRotation = angle;
-    if (!d_ptr->dirtyTransform)
-        d_ptr->invalidateSceneTransformCache();
-    d_ptr->dirtyTransform = 1;
-    d_ptr->hasTransform = 1;
-}
-
-/*!
-    \since 4.6
-
-    Returns the rotation around the Z axis.
-
-    The default is 0
-
-    \warning setting this property is conflicting with calling setTransform.
-    If a transform has been set, this function return the default value.
-
-    \sa setZRotation(), {Transformations}
-*/
-qreal QGraphicsItem::zRotation() const
-{
-    return d_ptr->decomposedTransform()->zRotation;
-}
-
-/*!
-    \since 4.6
-
-    Sets the rotation around the Z axis to \a angle degrees.
-
-    \warning setting this property is conflicting with calling setTransform.
-    If a transform has been set, it will be overwritten.
-
-    \sa zRotation(), {Transformations}
-*/
-void QGraphicsItem::setZRotation(qreal angle)
-{
-    if (!d_ptr->dirtyTransform) {
-        d_ptr->fullUpdateHelper(true);
-        prepareGeometryChange();
-    }
-    QGraphicsItemPrivate::DecomposedTransform *decomposed = d_ptr->decomposedTransform();
-    decomposed->zRotation = angle;
-    if (!d_ptr->dirtyTransform)
-        d_ptr->invalidateSceneTransformCache();
-    d_ptr->dirtyTransform = 1;
-    d_ptr->hasTransform = 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() 
-*/
-void QGraphicsItem::setRotation(qreal x, qreal y, qreal z)
-{
-    setXRotation(x);
-    setYRotation(y);
-    setZRotation(z);
-}
-
-/*!
-    \since 4.6
-
-    Returns the scale factor on the X axis.
-
-    The default is 1
-
-    \warning setting this property is conflicting with calling setTransform.
-    If a transform has been set, this function return the default value.
-
-    \sa setXScale(), {Transformations}
-*/
-qreal QGraphicsItem::xScale() const
-{
-    return d_ptr->decomposedTransform()->xScale;
-}
-
-/*!
-    \since 4.6
-
-    Sets the scale factor on the X axis to \a factor.
-
-    \warning setting this property is conflicting with calling setTransform.
-    If a transform has been set, it will be overwritten.
-
-    \sa xScale(), {Transformations}
-*/
-void QGraphicsItem::setXScale(qreal factor)
-{
-    if (!d_ptr->dirtyTransform) {
-        d_ptr->fullUpdateHelper(true);
-        prepareGeometryChange();
-    }
-    QGraphicsItemPrivate::DecomposedTransform *decomposed = d_ptr->decomposedTransform();
-    decomposed->xScale = factor;
-    if (!d_ptr->dirtyTransform)
-        d_ptr->invalidateSceneTransformCache();
-    d_ptr->dirtyTransform = 1;
-    d_ptr->hasTransform = 1;
-}
-
-/*!
-    \since 4.6
-
-    Returns the scale factor on the Y axis.
-
-    The default is 1
-
-    \warning setting this property is conflicting with calling setTransform.
-    If a transform has been set, this function return the default value.
-
-    \sa setYScale(), {Transformations}
-*/
-qreal QGraphicsItem::yScale() const
-{
-    return d_ptr->decomposedTransform()->yScale;
-}
-
-/*!
-    \since 4.6
-
-    Sets the scale factor on the Y axis to \a factor.
-
-    \warning setting this property is conflicting with calling setTransform.
-    If a transform has been set, it will be overwritten.
-
-    \sa yScale(), {Transformations}
-*/
-void QGraphicsItem::setYScale(qreal factor)
-{
-    if (!d_ptr->dirtyTransform) {
-        d_ptr->fullUpdateHelper(true);
-        prepareGeometryChange();
-    }
-    QGraphicsItemPrivate::DecomposedTransform *decomposed = d_ptr->decomposedTransform();
-    decomposed->yScale = factor;
-    if (!d_ptr->dirtyTransform)
-        d_ptr->invalidateSceneTransformCache();
-    d_ptr->dirtyTransform = 1;
-    d_ptr->hasTransform = 1;
-}
-
-/*!
-    \since 4.6
-
-    This convenience function set the scaling factors on X and Y axis to \a sx and \a sy.
-
-    \sa setXScale(), setYScale()
-*/
-void QGraphicsItem::setScale(qreal sx, qreal sy)
-{
-    setXScale(sx);
-    setYScale(sy);
-}
-
-/*!
-    \since 4.6
-
-    Returns the horizontal shear.
-
-    The default is 0
-
-    \warning setting this property is conflicting with calling setTransform.
-    If a transform has been set, this function return the default value.
-
-    \sa setHorizontalShear(), {Transformations}
-*/
-qreal QGraphicsItem::horizontalShear() const
-{
-    return d_ptr->decomposedTransform()->horizontalShear;
-}
-
-/*!
-    \since 4.6
-
-    Sets the horizontal shear to \a shear.
-
-    \warning setting this property is conflicting with calling setTransform.
-    If a transform has been set, it will be overwritten.
-
-    \sa horizontalShear(), {Transformations}
-*/
-void QGraphicsItem::setHorizontalShear(qreal shear)
-{
-    if (!d_ptr->dirtyTransform) {
-        d_ptr->fullUpdateHelper(true);
-        prepareGeometryChange();
-    }
-    QGraphicsItemPrivate::DecomposedTransform *decomposed = d_ptr->decomposedTransform();
-    decomposed->horizontalShear = shear;
-    if (!d_ptr->dirtyTransform)
-        d_ptr->invalidateSceneTransformCache();
-    d_ptr->dirtyTransform = 1;
-    d_ptr->hasTransform = 1;
-}
-
-/*!
-    \since 4.6
-
-    Returns the vertical shear.
-
-    The default is 0
-
-    \warning setting this property is conflicting with calling setTransform.
-    If a transform has been set, this function return the default value.
-
-    \sa setHorizontalShear(), {Transformations}
-*/
-qreal QGraphicsItem::verticalShear() const
-{
-    return d_ptr->decomposedTransform()->verticalShear;
-}
-
-/*!
-    \since 4.6
-
-    Sets the vertical shear to \a shear.
-
-    \warning setting this property is conflicting with calling setTransform.
-    If a transform has been set, it will be overwritten.
-
-    \sa verticalShear(), {Transformations}
-*/
-void QGraphicsItem::setVerticalShear(qreal shear)
-{
-    if (!d_ptr->dirtyTransform) {
-        d_ptr->fullUpdateHelper(true);
-        prepareGeometryChange();
-    }
-    QGraphicsItemPrivate::DecomposedTransform *decomposed = d_ptr->decomposedTransform();
-    decomposed->verticalShear = shear;
-    if (!d_ptr->dirtyTransform)
-        d_ptr->invalidateSceneTransformCache();
-    d_ptr->dirtyTransform = 1;
-    d_ptr->hasTransform = 1;
-}
-
-/*!
-    \since 4.6
-
-    This convenience function sets the horizontal shear to \a sh and the vertical shear to \a sv.
-
-    \sa setHorizontalShear(), setVerticalShear()
-*/
-void QGraphicsItem::setShear(qreal sh, qreal sv)
-{
-    setHorizontalShear(sh);
-    setVerticalShear(sv);
-}
-
-/*!
-    \since 4.6
-
-    Returns the transformation origin for the transformation properties.
-
-    The default is QPointF(0,0).
-
-    \warning setting this property is conflicting with calling setTransform.
-    If a transform has been set, this function return the default value.
-
-    \sa setTransformOrigin(), {Transformations}
-*/
-QPointF QGraphicsItem::transformOrigin() const
-{
-    const QGraphicsItemPrivate::DecomposedTransform *decomposed = d_ptr->decomposedTransform();
-    return QPointF(decomposed->xOrigin, decomposed->yOrigin);
-}
-
-/*!
-    \fn inline void setTransformOrigin(qreal x, qreal y)
-
-    \since 4.6
-
-    This is an overloaded member function, provided for convenience.
-    Sets the transformation origin for the transformation 
-    properties to the point(\a x, \a y).
-
-    \sa setTransformOrigin(), {Transformations}
-*/
-
-/*!
-    \since 4.6
-
-    Sets the transformation origin for the transformation properties to \a origin.
-    This does not apply to the transformation set by setTransform.
-
-    \warning setting this property is conflicting with calling setTransform.
-    If a transform has been set, it will be overwritten.
-
-    \sa transformOrigin(), {Transformations}
-*/
-void QGraphicsItem::setTransformOrigin(const QPointF &origin)
-{
-    if (!d_ptr->dirtyTransform) {
-        d_ptr->fullUpdateHelper(true);
-        prepareGeometryChange();
-    }
-    QGraphicsItemPrivate::DecomposedTransform *decomposed = d_ptr->decomposedTransform();
-    decomposed->xOrigin = origin.x();
-    decomposed->yOrigin = origin.y();
-    if (!d_ptr->dirtyTransform)
-        d_ptr->invalidateSceneTransformCache();
-    d_ptr->dirtyTransform = 1;
-    d_ptr->hasTransform = 1;
+    return *d_ptr->transform;
 }
 
 /*!
@@ -3306,11 +2915,7 @@ QTransform QGraphicsItem::itemTransform(const QGraphicsItem *other, bool *ok) co
 void QGraphicsItem::setMatrix(const QMatrix &matrix, bool combine)
 {
     QTransform oldTransform = this->transform();
-    QTransform newTransform;
-    if (!combine)
-        newTransform = QTransform(matrix);
-    else
-        newTransform = QTransform(matrix) * oldTransform;
+    QTransform newTransform(combine ? QTransform(matrix) * oldTransform : QTransform(matrix));
     if (oldTransform == newTransform)
         return;
 
@@ -3324,9 +2929,10 @@ void QGraphicsItem::setMatrix(const QMatrix &matrix, bool combine)
     // Update and set the new transformation.
     prepareGeometryChange();
     d_ptr->hasTransform = !newTransform.isIdentity();
-    d_ptr->setExtra(QGraphicsItemPrivate::ExtraTransform, newTransform);
-    d_ptr->dirtyTransformComponents = 1;
-    d_ptr->dirtyTransform = 0;
+    if(!d_ptr->transform)
+        d_ptr->transform = new QTransform(newTransform);
+    else
+        *d_ptr->transform = newTransform;
     d_ptr->invalidateSceneTransformCache();
 
     // Send post-notification.
@@ -3358,11 +2964,7 @@ void QGraphicsItem::setMatrix(const QMatrix &matrix, bool combine)
 void QGraphicsItem::setTransform(const QTransform &matrix, bool combine)
 {
     QTransform oldTransform = this->transform();
-    QTransform newTransform;
-    if (!combine)
-        newTransform = matrix;
-    else
-        newTransform = matrix * oldTransform;
+    QTransform newTransform(combine ? matrix * oldTransform : matrix);
     if (oldTransform == newTransform)
         return;
 
@@ -3376,9 +2978,10 @@ void QGraphicsItem::setTransform(const QTransform &matrix, bool combine)
     // Update and set the new transformation.
     prepareGeometryChange();
     d_ptr->hasTransform = !newTransform.isIdentity();
-    d_ptr->setExtra(QGraphicsItemPrivate::ExtraTransform, newTransform);
-    d_ptr->dirtyTransformComponents = 1;
-    d_ptr->dirtyTransform = 0;
+    if(!d_ptr->transform)
+        d_ptr->transform = new QTransform(newTransform);
+    else
+        *d_ptr->transform = newTransform;
     d_ptr->invalidateSceneTransformCache();
 
     // Send post-notification.
@@ -6359,7 +5962,7 @@ void QGraphicsItem::prepareGeometryChange()
     }
 
     QGraphicsItem *parent = this;
-    while (parent = parent->d_ptr->parent)
+    while ((parent = parent->d_ptr->parent))
         parent->d_ptr->dirtyChildrenBoundingRect = 1;
 
     if (d_ptr->inSetPosHelper)