Merge branch '4.6' of git@scm.dev.nokia.troll.no:qt/qt into 4.6

16 files changed, 529 insertions, 236 deletions

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout.cpp b/src/gui/graphicsview/qgraphicsanchorlayout.cpp
index e21cd99..56d70e1 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout.cpp
@@ -123,7 +123,7 @@
 
 */
 #include "qgraphicsanchorlayout_p.h"
-
+#ifndef QT_NO_GRAPHICSVIEW
 QT_BEGIN_NAMESPACE
 
 QGraphicsAnchor::QGraphicsAnchor(QGraphicsAnchorLayout *parentLayout)
@@ -420,7 +420,7 @@ void QGraphicsAnchorLayout::setSpacing(qreal spacing)
 qreal QGraphicsAnchorLayout::horizontalSpacing() const
 {
     Q_D(const QGraphicsAnchorLayout);
-    return d->effectiveSpacing(QGraphicsAnchorLayoutPrivate::Horizontal);
+    return d->styleInfo().defaultSpacing(Qt::Horizontal);
 }
 
 /*!
@@ -431,7 +431,7 @@ qreal QGraphicsAnchorLayout::horizontalSpacing() const
 qreal QGraphicsAnchorLayout::verticalSpacing() const
 {
     Q_D(const QGraphicsAnchorLayout);
-    return d->effectiveSpacing(QGraphicsAnchorLayoutPrivate::Vertical);
+    return d->styleInfo().defaultSpacing(Qt::Vertical);
 }
 
 /*!
@@ -501,7 +501,8 @@ void QGraphicsAnchorLayout::invalidate()
 {
     Q_D(QGraphicsAnchorLayout);
     QGraphicsLayout::invalidate();
-    d->calculateGraphCacheDirty = 1;
+    d->calculateGraphCacheDirty = true;
+    d->styleInfoDirty = true;
 }
 
 /*!
@@ -535,3 +536,4 @@ QSizeF QGraphicsAnchorLayout::sizeHint(Qt::SizeHint which, const QSizeF &constra
 }
 
 QT_END_NAMESPACE
+#endif //QT_NO_GRAPHICSVIEW
diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
index 8c8c303..41aa8aa 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
@@ -40,6 +40,7 @@
 ****************************************************************************/
 
 #include <QtGui/qwidget.h>
+#include <QtGui/qapplication.h>
 #include <QtCore/qlinkedlist.h>
 #include <QtCore/qstack.h>
 
@@ -48,7 +49,7 @@
 #endif
 
 #include "qgraphicsanchorlayout_p.h"
-
+#ifndef QT_NO_GRAPHICSVIEW
 QT_BEGIN_NAMESPACE
 
 
@@ -141,34 +142,25 @@ static void internalSizeHints(QSizePolicy::Policy policy,
         *expSize = *prefSize;
 }
 
-void AnchorData::refreshSizeHints(qreal effectiveSpacing)
+bool AnchorData::refreshSizeHints(const QLayoutStyleInfo *styleInfo)
 {
-    const bool isInternalAnchor = from->m_item == to->m_item;
-
     QSizePolicy::Policy policy;
     qreal minSizeHint;
     qreal prefSizeHint;
     qreal maxSizeHint;
 
-    if (isInternalAnchor) {
-        const QGraphicsAnchorLayoutPrivate::Orientation orient =
-            QGraphicsAnchorLayoutPrivate::edgeOrientation(from->m_edge);
-        const Qt::AnchorPoint centerEdge =
-            QGraphicsAnchorLayoutPrivate::pickEdge(Qt::AnchorHorizontalCenter, orient);
-        bool hasCenter = (from->m_edge == centerEdge || to->m_edge == centerEdge);
-
+    // It is an internal anchor
+    if (item) {
         if (isLayoutAnchor) {
             minSize = 0;
             prefSize = 0;
             expSize = 0;
             maxSize = QWIDGETSIZE_MAX;
-            if (hasCenter)
+            if (isCenterAnchor)
                 maxSize /= 2;
-            return;
+            return true;
         } else {
-
-            QGraphicsLayoutItem *item = from->m_item;
-            if (orient == QGraphicsAnchorLayoutPrivate::Horizontal) {
+            if (orientation == QGraphicsAnchorLayoutPrivate::Horizontal) {
                 policy = item->sizePolicy().horizontalPolicy();
                 minSizeHint = item->effectiveSizeHint(Qt::MinimumSize).width();
                 prefSizeHint = item->effectiveSizeHint(Qt::PreferredSize).width();
@@ -180,7 +172,7 @@ void AnchorData::refreshSizeHints(qreal effectiveSpacing)
                 maxSizeHint = item->effectiveSizeHint(Qt::MaximumSize).height();
             }
 
-            if (hasCenter) {
+            if (isCenterAnchor) {
                 minSizeHint /= 2;
                 prefSizeHint /= 2;
                 maxSizeHint /= 2;
@@ -196,7 +188,20 @@ void AnchorData::refreshSizeHints(qreal effectiveSpacing)
             // their effective size hints might be narrowed down due to their size policies.
             prefSizeHint = prefSize;
         } else {
-            prefSizeHint = effectiveSpacing;
+            const Qt::Orientation orient = Qt::Orientation(QGraphicsAnchorLayoutPrivate::edgeOrientation(from->m_edge) + 1);
+            qreal s = styleInfo->defaultSpacing(orient);
+            if (s < 0) {
+                QSizePolicy::ControlType controlTypeFrom = from->m_item->sizePolicy().controlType();
+                QSizePolicy::ControlType controlTypeTo = to->m_item->sizePolicy().controlType();
+                s = styleInfo->perItemSpacing(controlTypeFrom, controlTypeTo, orient);
+
+                // ### Currently we do not support negative anchors inside the graph.
+                // To avoid those being created by a negative style spacing, we must
+                // make this test.
+                if (s < 0)
+                    s = 0;
+            }
+            prefSizeHint = s;
         }
         maxSizeHint = QWIDGETSIZE_MAX;
     }
@@ -214,6 +219,8 @@ void AnchorData::refreshSizeHints(qreal effectiveSpacing)
     sizeAtPreferred = prefSize;
     sizeAtExpanding = prefSize;
     sizeAtMaximum = prefSize;
+
+    return true;
 }
 
 void ParallelAnchorData::updateChildrenSizes()
@@ -227,26 +234,29 @@ void ParallelAnchorData::updateChildrenSizes()
     secondEdge->updateChildrenSizes();
 }
 
-void ParallelAnchorData::refreshSizeHints(qreal effectiveSpacing)
+bool ParallelAnchorData::refreshSizeHints(const QLayoutStyleInfo *styleInfo)
 {
-    refreshSizeHints_helper(effectiveSpacing);
+    return refreshSizeHints_helper(styleInfo);
 }
 
-void ParallelAnchorData::refreshSizeHints_helper(qreal effectiveSpacing,
+bool ParallelAnchorData::refreshSizeHints_helper(const QLayoutStyleInfo *styleInfo,
                                                  bool refreshChildren)
 {
-    if (refreshChildren) {
-        firstEdge->refreshSizeHints(effectiveSpacing);
-        secondEdge->refreshSizeHints(effectiveSpacing);
+    if (refreshChildren && (!firstEdge->refreshSizeHints(styleInfo)
+                            || !secondEdge->refreshSizeHints(styleInfo))) {
+        return false;
     }
 
-    // ### should we warn if the parallel connection is invalid?
-    // e.g. 1-2-3 with 10-20-30, the minimum of the latter is
-    // bigger than the maximum of the former.
-
     minSize = qMax(firstEdge->minSize, secondEdge->minSize);
     maxSize = qMin(firstEdge->maxSize, secondEdge->maxSize);
 
+    // This condition means that the maximum size of one anchor being simplified is smaller than
+    // the minimum size of the other anchor. The consequence is that there won't be a valid size
+    // for this parallel setup.
+    if (minSize > maxSize) {
+        return false;
+    }
+
     expSize = qMax(firstEdge->expSize, secondEdge->expSize);
     expSize = qMin(expSize, maxSize);
 
@@ -258,6 +268,8 @@ void ParallelAnchorData::refreshSizeHints_helper(qreal effectiveSpacing,
     sizeAtPreferred = prefSize;
     sizeAtExpanding = prefSize;
     sizeAtMaximum = prefSize;
+
+    return true;
 }
 
 /*!
@@ -362,12 +374,12 @@ void SequentialAnchorData::updateChildrenSizes()
     }
 }
 
-void SequentialAnchorData::refreshSizeHints(qreal effectiveSpacing)
+bool SequentialAnchorData::refreshSizeHints(const QLayoutStyleInfo *styleInfo)
 {
-    refreshSizeHints_helper(effectiveSpacing);
+    return refreshSizeHints_helper(styleInfo);
 }
 
-void SequentialAnchorData::refreshSizeHints_helper(qreal effectiveSpacing,
+bool SequentialAnchorData::refreshSizeHints_helper(const QLayoutStyleInfo *styleInfo,
                                                    bool refreshChildren)
 {
     minSize = 0;
@@ -379,8 +391,8 @@ void SequentialAnchorData::refreshSizeHints_helper(qreal effectiveSpacing,
         AnchorData *edge = m_edges.at(i);
 
         // If it's the case refresh children information first
-        if (refreshChildren)
-            edge->refreshSizeHints(effectiveSpacing);
+        if (refreshChildren && !edge->refreshSizeHints(styleInfo))
+            return false;
 
         minSize += edge->minSize;
         prefSize += edge->prefSize;
@@ -393,6 +405,8 @@ void SequentialAnchorData::refreshSizeHints_helper(qreal effectiveSpacing,
     sizeAtPreferred = prefSize;
     sizeAtExpanding = prefSize;
     sizeAtMaximum = prefSize;
+
+    return true;
 }
 
 #ifdef QT_DEBUG
@@ -458,7 +472,7 @@ QString GraphPath::toString() const
 #endif
 
 QGraphicsAnchorLayoutPrivate::QGraphicsAnchorLayoutPrivate()
-    : calculateGraphCacheDirty(1)
+    : calculateGraphCacheDirty(true), styleInfoDirty(true)
 {
     for (int i = 0; i < NOrientations; ++i) {
         for (int j = 0; j < 3; ++j) {
@@ -510,18 +524,49 @@ inline static qreal checkAdd(qreal a, qreal b)
 }
 
 /*!
- * \internal
- *
- * Takes the sequence of vertices described by (\a before, \a vertices, \a after) and replaces
- * all anchors connected to the vertices in \a vertices with one simplified anchor between
- * \a before and \a after. The simplified anchor will be a placeholder for all the previous
- * anchors between \a before and \a after, and can be restored back to the anchors it is a
- * placeholder for.
- */
-static bool simplifySequentialChunk(Graph<AnchorVertex, AnchorData> *graph,
-                                    AnchorVertex *before,
-                                    const QVector<AnchorVertex*> &vertices,
-                                    AnchorVertex *after)
+    \internal
+
+    Adds \a newAnchor to the graph \a g.
+
+    Returns the newAnchor itself if it could be added without further changes to the graph. If a
+    new parallel anchor had to be created, then returns the new parallel anchor. In case the
+    addition is unfeasible -- because a parallel setup is not possible, returns 0.
+*/
+static AnchorData *addAnchorMaybeParallel(Graph<AnchorVertex, AnchorData> *g,
+                                          AnchorData *newAnchor)
+{
+    bool feasible = true;
+
+    // If already exists one anchor where newAnchor is supposed to be, we create a parallel
+    // anchor.
+    if (AnchorData *oldAnchor = g->takeEdge(newAnchor->from, newAnchor->to)) {
+        ParallelAnchorData *parallel = new ParallelAnchorData(oldAnchor, newAnchor);
+
+        // At this point we can identify that the parallel anchor is not feasible, e.g. one
+        // anchor minimum size is bigger than the other anchor maximum size.
+        feasible = parallel->refreshSizeHints_helper(0, false);
+        newAnchor = parallel;
+    }
+
+    g->createEdge(newAnchor->from, newAnchor->to, newAnchor);
+    return feasible ? newAnchor : 0;
+}
+
+
+/*!
+    \internal
+
+    Takes the sequence of vertices described by (\a before, \a vertices, \a after) and removes
+    all anchors connected to the vertices in \a vertices, returning one simplified anchor between
+    \a before and \a after.
+
+    Note that this function doesn't add the created anchor to the graph. This should be done by
+    the caller.
+*/
+static AnchorData *createSequence(Graph<AnchorVertex, AnchorData> *graph,
+                                  AnchorVertex *before,
+                                  const QVector<AnchorVertex*> &vertices,
+                                  AnchorVertex *after)
 {
     AnchorData *data = graph->edgeData(before, vertices.first());
     Q_ASSERT(data);
@@ -546,41 +591,24 @@ static bool simplifySequentialChunk(Graph<AnchorVertex, AnchorData> *graph,
     qDebug("simplifying [%s] to [%s - %s]", qPrintable(strPath), qPrintable(before->toString()), qPrintable(after->toString()));
 #endif
 
-    SequentialAnchorData *sequence = new SequentialAnchorData;
     AnchorVertex *prev = before;
+    QVector<AnchorData *> edges;
 
     for (int i = 0; i <= orderedVertices.count(); ++i) {
         AnchorVertex *next = (i < orderedVertices.count()) ? orderedVertices.at(i) : after;
         AnchorData *ad = graph->takeEdge(prev, next);
         Q_ASSERT(ad);
-        sequence->m_edges.append(ad);
+        edges.append(ad);
         prev = next;
     }
 
-    sequence->setVertices(orderedVertices);
+    SequentialAnchorData *sequence = new SequentialAnchorData(orderedVertices, edges);
     sequence->from = before;
     sequence->to = after;
 
     sequence->refreshSizeHints_helper(0, false);
 
-    // Note that since layout 'edges' can't be simplified away from
-    // the graph, it's safe to assume that if there's a layout
-    // 'edge', it'll be in the boundaries of the sequence.
-    sequence->isLayoutAnchor = (sequence->m_edges.first()->isLayoutAnchor
-                                || sequence->m_edges.last()->isLayoutAnchor);
-
-    AnchorData *newAnchor = sequence;
-    if (AnchorData *oldAnchor = graph->takeEdge(before, after)) {
-        ParallelAnchorData *parallel = new ParallelAnchorData(oldAnchor, sequence);
-        parallel->isLayoutAnchor = (oldAnchor->isLayoutAnchor
-                                     || sequence->isLayoutAnchor);
-        parallel->refreshSizeHints_helper(0, false);
-        newAnchor = parallel;
-    }
-    graph->createEdge(before, after, newAnchor);
-
-    // True if we created a parallel anchor
-    return newAnchor != sequence;
+    return sequence;
 }
 
 /*!
@@ -617,15 +645,17 @@ static bool simplifySequentialChunk(Graph<AnchorVertex, AnchorData> *graph,
    2. Go to (1)
    3. Done
 
+   When creating the parallel anchors, the algorithm might identify unfeasible situations. In this
+   case the simplification process stops and returns false. Otherwise returns true.
 */
-void QGraphicsAnchorLayoutPrivate::simplifyGraph(Orientation orientation)
+bool QGraphicsAnchorLayoutPrivate::simplifyGraph(Orientation orientation)
 {
     static bool noSimplification = !qgetenv("QT_ANCHORLAYOUT_NO_SIMPLIFICATION").isEmpty();
     if (noSimplification || items.isEmpty())
-        return;
+        return true;
 
     if (graphSimplified[orientation])
-        return;
+        return true;
     graphSimplified[orientation] = true;
 
 #if 0
@@ -634,12 +664,18 @@ void QGraphicsAnchorLayoutPrivate::simplifyGraph(Orientation orientation)
 #endif
 
     if (!graph[orientation].rootVertex())
-        return;
+        return true;
 
     bool dirty;
+    bool feasible = true;
     do {
-        dirty = simplifyGraphIteration(orientation);
-    } while (dirty);
+        dirty = simplifyGraphIteration(orientation, &feasible);
+    } while (dirty && feasible);
+
+    if (!feasible)
+        graphSimplified[orientation] = false;
+
+    return feasible;
 }
 
 /*!
@@ -656,7 +692,8 @@ void QGraphicsAnchorLayoutPrivate::simplifyGraph(Orientation orientation)
     Note that there are some catches to this that are not covered by the above explanation, see
     the function comments for more details.
 */
-bool QGraphicsAnchorLayoutPrivate::simplifyGraphIteration(QGraphicsAnchorLayoutPrivate::Orientation orientation)
+bool QGraphicsAnchorLayoutPrivate::simplifyGraphIteration(QGraphicsAnchorLayoutPrivate::Orientation orientation,
+                                                          bool *feasible)
 {
     Q_Q(QGraphicsAnchorLayout);
     Graph<AnchorVertex, AnchorData> &g = graph[orientation];
@@ -667,8 +704,6 @@ bool QGraphicsAnchorLayoutPrivate::simplifyGraphIteration(QGraphicsAnchorLayoutP
     QVector<AnchorVertex*> candidates;
     bool candidatesForward;
 
-    const Qt::AnchorPoint centerEdge = pickEdge(Qt::AnchorHorizontalCenter, orientation);
-
     // Walk depth-first, in the stack we store start of the candidate sequence (beforeSequence)
     // and the vertex to be visited.
     while (!stack.isEmpty()) {
@@ -777,7 +812,8 @@ bool QGraphicsAnchorLayoutPrivate::simplifyGraphIteration(QGraphicsAnchorLayoutP
 
         // One restriction we have is to not simplify half of an anchor and let the other half
         // unsimplified. So we remove center edges before and after the sequence.
-        if (beforeSequence->m_edge == centerEdge && beforeSequence->m_item == candidates.first()->m_item) {
+        const AnchorData *firstAnchor = g.edgeData(beforeSequence, candidates.first());
+        if (firstAnchor->isCenterAnchor) {
             beforeSequence = candidates.first();
             candidates.remove(0);
 
@@ -786,7 +822,8 @@ bool QGraphicsAnchorLayoutPrivate::simplifyGraphIteration(QGraphicsAnchorLayoutP
                 continue;
         }
 
-        if (afterSequence->m_edge == centerEdge && afterSequence->m_item == candidates.last()->m_item) {
+        const AnchorData *lastAnchor = g.edgeData(candidates.last(), afterSequence);
+        if (lastAnchor->isCenterAnchor) {
             afterSequence = candidates.last();
             candidates.remove(candidates.count() - 1);
 
@@ -794,11 +831,26 @@ bool QGraphicsAnchorLayoutPrivate::simplifyGraphIteration(QGraphicsAnchorLayoutP
                 continue;
         }
 
-        // This function will remove the candidates from the graph and create one edge between
-        // beforeSequence and afterSequence. This function returns true if the sequential
-        // simplification also caused a parallel simplification to be created. In this case we end
-        // the iteration and start again (since all the visited state we have may be outdated).
-        if (simplifySequentialChunk(&g, beforeSequence, candidates, afterSequence))
+        //
+        // Add the sequence to the graph.
+        //
+
+        AnchorData *sequence = createSequence(&g, beforeSequence, candidates, afterSequence);
+
+        // If 'beforeSequence' and 'afterSequence' already had an anchor between them, we'll
+        // create a parallel anchor between the new sequence and the old anchor.
+        AnchorData *newAnchor = addAnchorMaybeParallel(&g, sequence);
+
+        if (!newAnchor) {
+            *feasible = false;
+            return false;
+        }
+
+        // When a new parallel anchor is create in the graph, we finish the iteration and return
+        // true to indicate a new iteration is needed. This happens because a parallel anchor
+        // changes the number of adjacents one vertex has, possibly opening up oportunities for
+        // building candidate lists (when adjacents == 2).
+        if (newAnchor != sequence)
             return true;
 
         // If there was no parallel simplification, we'll keep walking the graph. So we clear the
@@ -1008,11 +1060,13 @@ void QGraphicsAnchorLayoutPrivate::createCenterAnchors(
     AnchorData *data = new AnchorData;
     c->variables.insert(data, 1.0);
     addAnchor_helper(item, firstEdge, item, centerEdge, data);
+    data->isCenterAnchor = true;
     data->refreshSizeHints(0);
 
     data = new AnchorData;
     c->variables.insert(data, -1.0);
     addAnchor_helper(item, centerEdge, item, lastEdge, data);
+    data->isCenterAnchor = true;
     data->refreshSizeHints(0);
 
     itemCenterConstraints[orientation].append(c);
@@ -1234,9 +1288,11 @@ void QGraphicsAnchorLayoutPrivate::addAnchor_helper(QGraphicsLayoutItem *firstIt
 {
     Q_Q(QGraphicsAnchorLayout);
 
+    const Orientation orientation = edgeOrientation(firstEdge);
+
     // Guarantee that the graph is no simplified when adding this anchor,
     // anchor manipulation always happen in the full graph
-    restoreSimplifiedGraph(edgeOrientation(firstEdge));
+    restoreSimplifiedGraph(orientation);
 
     // Is the Vertex (firstItem, firstEdge) already represented in our
     // internal structure?
@@ -1245,10 +1301,16 @@ void QGraphicsAnchorLayoutPrivate::addAnchor_helper(QGraphicsLayoutItem *firstIt
 
     // Remove previous anchor
     // ### Could we update the existing edgeData rather than creating a new one?
-    if (graph[edgeOrientation(firstEdge)].edgeData(v1, v2)) {
+    if (graph[orientation].edgeData(v1, v2)) {
         removeAnchor_helper(v1, v2);
     }
 
+    // If its an internal anchor, set the associated item
+    if (firstItem == secondItem)
+        data->item = firstItem;
+
+    data->orientation = orientation;
+
     // Create a bi-directional edge in the sense it can be transversed both
     // from v1 or v2. "data" however is shared between the two references
     // so we still know that the anchor direction is from 1 to 2.
@@ -1257,10 +1319,11 @@ void QGraphicsAnchorLayoutPrivate::addAnchor_helper(QGraphicsLayoutItem *firstIt
 #ifdef QT_DEBUG
     data->name = QString::fromAscii("%1 --to--> %2").arg(v1->toString()).arg(v2->toString());
 #endif
-    // Keep track of anchors that are connected to the layout 'edges'
-    data->isLayoutAnchor = (v1->m_item == q || v2->m_item == q);
+    // ### bit to track internal anchors, since inside AnchorData methods
+    // we don't have access to the 'q' pointer.
+    data->isLayoutAnchor = (data->item == q);
 
-    graph[edgeOrientation(firstEdge)].createEdge(v1, v2, data);
+    graph[orientation].createEdge(v1, v2, data);
 }
 
 QGraphicsAnchor *QGraphicsAnchorLayoutPrivate::getAnchor(QGraphicsLayoutItem *firstItem,
@@ -1425,7 +1488,7 @@ void QGraphicsAnchorLayoutPrivate::anchorSize(const AnchorData *data,
     Q_ASSERT(minSize || prefSize || maxSize);
     Q_ASSERT(data);
     QGraphicsAnchorLayoutPrivate *that = const_cast<QGraphicsAnchorLayoutPrivate *>(this);
-    that->restoreSimplifiedGraph(edgeOrientation(data->from->m_edge));
+    that->restoreSimplifiedGraph(Orientation(data->orientation));
 
     if (minSize)
         *minSize = data->minSize;
@@ -1565,34 +1628,32 @@ void QGraphicsAnchorLayoutPrivate::correctEdgeDirection(QGraphicsLayoutItem *&fi
     }
 }
 
-qreal QGraphicsAnchorLayoutPrivate::effectiveSpacing(Orientation orientation) const
+QLayoutStyleInfo &QGraphicsAnchorLayoutPrivate::styleInfo() const
 {
-    Q_Q(const QGraphicsAnchorLayout);
-    qreal s = spacings[orientation];
-    if (s < 0) {
-        // ### make sure behaviour is the same as in QGraphicsGridLayout
+    if (styleInfoDirty) {
+        Q_Q(const QGraphicsAnchorLayout);
+        //### Fix this if QGV ever gets support for Metal style or different Aqua sizes.
+        QWidget *wid = 0;
+
         QGraphicsLayoutItem *parent = q->parentLayoutItem();
         while (parent && parent->isLayout()) {
             parent = parent->parentLayoutItem();
         }
+        QGraphicsWidget *w = 0;
         if (parent) {
             QGraphicsItem *parentItem = parent->graphicsItem();
-            if (parentItem && parentItem->isWidget()) {
-                QGraphicsWidget *w = static_cast<QGraphicsWidget*>(parentItem);
-                s = w->style()->pixelMetric(orientation == Horizontal
-                                            ? QStyle::PM_LayoutHorizontalSpacing
-                                            : QStyle::PM_LayoutVerticalSpacing);
-            }
+            if (parentItem && parentItem->isWidget())
+                w = static_cast<QGraphicsWidget*>(parentItem);
         }
-    }
 
-    // ### Currently we do not support negative anchors inside the graph.
-    // To avoid those being created by a negative style spacing, we must
-    // make this test.
-    if (s < 0)
-        s = 0;
+        QStyle *style = w ? w->style() : QApplication::style();
+        cachedStyleInfo = QLayoutStyleInfo(style, wid);
+        cachedStyleInfo.setDefaultSpacing(Qt::Horizontal, spacings[0]);
+        cachedStyleInfo.setDefaultSpacing(Qt::Vertical, spacings[1]);
 
-    return s;
+        styleInfoDirty = false;
+    }
+    return cachedStyleInfo;
 }
 
 /*!
@@ -1620,7 +1681,7 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs()
     dumpGraph(QString::fromAscii("%1-after").arg(count));
 #endif
 
-    calculateGraphCacheDirty = 0;
+    calculateGraphCacheDirty = false;
 }
 
 // ### Maybe getGraphParts could return the variables when traversing, at least
@@ -1638,38 +1699,52 @@ QList<AnchorData *> getVariables(QList<QSimplexConstraint *> constraints)
 }
 
 /*!
-  \internal
+    \internal
 
-  Calculate graphs is the method that puts together all the helper routines
-  so that the AnchorLayout can calculate the sizes of each item.
+    Calculate graphs is the method that puts together all the helper routines
+    so that the AnchorLayout can calculate the sizes of each item.
 
-  In a nutshell it should do:
+    In a nutshell it should do:
 
-  1) Update anchor nominal sizes, that is, the size that each anchor would
-     have if no other restrictions applied. This is done by quering the
-     layout style and the sizeHints of the items belonging to the layout.
+    1) Refresh anchor nominal sizes, that is, the size that each anchor would
+       have if no other restrictions applied. This is done by quering the
+       layout style and the sizeHints of the items belonging to the layout.
 
-  2) Simplify the graph by grouping together parallel and sequential anchors
-     into "group anchors". These have equivalent minimum, preferred and maximum
-     sizeHints as the anchors they replace.
+    2) Simplify the graph by grouping together parallel and sequential anchors
+       into "group anchors". These have equivalent minimum, preferred and maximum
+       sizeHints as the anchors they replace.
 
-  3) Check if we got to a trivial case. In some cases, the whole graph can be
-     simplified into a single anchor. If so, use this information. If not,
-     then call the Simplex solver to calculate the anchors sizes.
+    3) Check if we got to a trivial case. In some cases, the whole graph can be
+       simplified into a single anchor. If so, use this information. If not,
+       then call the Simplex solver to calculate the anchors sizes.
 
-  4) Once the root anchors had its sizes calculated, propagate that to the
-     anchors they represent.
+    4) Once the root anchors had its sizes calculated, propagate that to the
+       anchors they represent.
 */
 void QGraphicsAnchorLayoutPrivate::calculateGraphs(
     QGraphicsAnchorLayoutPrivate::Orientation orientation)
 {
     Q_Q(QGraphicsAnchorLayout);
 
-    // Simplify the graph
-    simplifyGraph(orientation);
+#if defined(QT_DEBUG) || defined(Q_AUTOTEST_EXPORT)
+    lastCalculationUsedSimplex[orientation] = false;
+#endif
 
-    // Reset the nominal sizes of each anchor based on the current item sizes
-    setAnchorSizeHintsFromItems(orientation);
+    // Reset the nominal sizes of each anchor based on the current item sizes.  This function
+    // works with both simplified and non-simplified graphs, so it'll work when the
+    // simplification is going to be reused.
+    if (!refreshAllSizeHints(orientation)) {
+        qWarning("QGraphicsAnchorLayout: anchor setup is not feasible.");
+        graphHasConflicts[orientation] = true;
+        return;
+    }
+
+    // Simplify the graph
+    if (!simplifyGraph(orientation)) {
+        qWarning("QGraphicsAnchorLayout: anchor setup is not feasible.");
+        graphHasConflicts[orientation] = true;
+        return;
+    }
 
     // Traverse all graph edges and store the possible paths to each vertex
     findPaths(orientation);
@@ -1837,23 +1912,31 @@ bool QGraphicsAnchorLayoutPrivate::calculateNonTrunk(const QList<QSimplexConstra
 }
 
 /*!
-  \internal
+    \internal
+
+    Traverse the graph refreshing the size hints. Complex anchors will call the
+    refresh method of their children anchors. Simple anchors, if are internal
+    anchors, will query the associated item for their size hints.
 
-  For graph edges ("anchors") that represent items, this method updates their
-  intrinsic size restrictions, based on the item size hints.
+    Returns false if some unfeasibility was found in the graph regarding the
+    complex anchors.
 */
-void QGraphicsAnchorLayoutPrivate::setAnchorSizeHintsFromItems(Orientation orientation)
+bool QGraphicsAnchorLayoutPrivate::refreshAllSizeHints(Orientation orientation)
 {
     Graph<AnchorVertex, AnchorData> &g = graph[orientation];
     QList<QPair<AnchorVertex *, AnchorVertex *> > vertices = g.connections();
 
-    qreal spacing = effectiveSpacing(orientation);
-
+    QLayoutStyleInfo styleInf = styleInfo();
     for (int i = 0; i < vertices.count(); ++i) {
         AnchorData *data = g.edgeData(vertices.at(i).first, vertices.at(i).second);;
         Q_ASSERT(data->from && data->to);
-        data->refreshSizeHints(spacing);
+
+        // During the traversal we check the feasibility of the complex anchors.
+        if (!data->refreshSizeHints(&styleInf))
+            return false;
     }
+
+    return true;
 }
 
 /*!
@@ -1960,17 +2043,27 @@ QList<QSimplexConstraint *> QGraphicsAnchorLayoutPrivate::constraintsFromSizeHin
 {
     QList<QSimplexConstraint *> anchorConstraints;
     for (int i = 0; i < anchors.size(); ++i) {
-        QSimplexConstraint *c = new QSimplexConstraint;
-        c->variables.insert(anchors[i], 1.0);
-        c->constant = anchors[i]->minSize;
-        c->ratio = QSimplexConstraint::MoreOrEqual;
-        anchorConstraints += c;
-
-        c = new QSimplexConstraint;
-        c->variables.insert(anchors[i], 1.0);
-        c->constant = anchors[i]->maxSize;
-        c->ratio = QSimplexConstraint::LessOrEqual;
-        anchorConstraints += c;
+        AnchorData *ad = anchors[i];
+
+        if ((ad->minSize == ad->maxSize) || qFuzzyCompare(ad->minSize, ad->maxSize)) {
+            QSimplexConstraint *c = new QSimplexConstraint;
+            c->variables.insert(ad, 1.0);
+            c->constant = ad->minSize;
+            c->ratio = QSimplexConstraint::Equal;
+            anchorConstraints += c;
+        } else {
+            QSimplexConstraint *c = new QSimplexConstraint;
+            c->variables.insert(ad, 1.0);
+            c->constant = ad->minSize;
+            c->ratio = QSimplexConstraint::MoreOrEqual;
+            anchorConstraints += c;
+
+            c = new QSimplexConstraint;
+            c->variables.insert(ad, 1.0);
+            c->constant = ad->maxSize;
+            c->ratio = QSimplexConstraint::LessOrEqual;
+            anchorConstraints += c;
+        }
     }
 
     return anchorConstraints;
@@ -2110,8 +2203,8 @@ void QGraphicsAnchorLayoutPrivate::identifyNonFloatItems_helper(const AnchorData
 
     switch(ad->type) {
     case AnchorData::Normal:
-        if (ad->from->m_item == ad->to->m_item && ad->to->m_item != q)
-            nonFloatingItemsIdentifiedSoFar->insert(ad->to->m_item);
+        if (ad->item && ad->item != q)
+            nonFloatingItemsIdentifiedSoFar->insert(ad->item);
         break;
     case AnchorData::Sequential:
         foreach (const AnchorData *d, static_cast<const SequentialAnchorData *>(ad)->m_edges)
@@ -2377,7 +2470,7 @@ bool QGraphicsAnchorLayoutPrivate::solveMinMax(const QList<QSimplexConstraint *>
         *min = simplex.solveMin();
 
         // Save sizeAtMinimum results
-        QList<QSimplexVariable *> variables = simplex.constraintsVariables();
+        QList<AnchorData *> variables = getVariables(constraints);
         for (int i = 0; i < variables.size(); ++i) {
             AnchorData *ad = static_cast<AnchorData *>(variables[i]);
             Q_ASSERT(ad->result >= ad->minSize || qFuzzyCompare(ad->result, ad->minSize));
@@ -2536,7 +2629,7 @@ void QGraphicsAnchorLayoutPrivate::solveExpanding(const QList<QSimplexConstraint
             hasExpanding = true;
 
         // Lock anchor between boundedExpSize and sizeAtMaximum (ensure 3.a)
-        if (boundedExpSize == ad->sizeAtMaximum) {
+        if (boundedExpSize == ad->sizeAtMaximum || qFuzzyCompare(boundedExpSize, ad->sizeAtMaximum)) {
             // The interval has only one possible value, we can use an "Equal"
             // constraint and don't need to add this variable to the objective.
             QSimplexConstraint *itemC = new QSimplexConstraint;
@@ -2635,3 +2728,4 @@ void QGraphicsAnchorLayoutPrivate::dumpGraph(const QString &name)
 #endif
 
 QT_END_NAMESPACE
+#endif //QT_NO_GRAPHICSVIEW
diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.h b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
index d45c004..7dd0d65 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.h
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
@@ -60,7 +60,7 @@
 #include "qgraphicsanchorlayout.h"
 #include "qgraph_p.h"
 #include "qsimplex_p.h"
-
+#ifndef QT_NO_GRAPHICSVIEW
 QT_BEGIN_NAMESPACE
 
 /*
@@ -151,15 +151,16 @@ struct AnchorData : public QSimplexVariable {
     };
 
     AnchorData()
-        : QSimplexVariable(), from(0), to(0),
+        : QSimplexVariable(), item(0), from(0), to(0),
           minSize(0), prefSize(0), expSize(0), maxSize(0),
           sizeAtMinimum(0), sizeAtPreferred(0),
           sizeAtExpanding(0), sizeAtMaximum(0),
           graphicsAnchor(0), skipInPreferred(0),
-          type(Normal), hasSize(true), isLayoutAnchor(false) {}
+          type(Normal), hasSize(true), isLayoutAnchor(false),
+          isCenterAnchor(false), orientation(0) {}
 
     virtual void updateChildrenSizes() {}
-    virtual void refreshSizeHints(qreal effectiveSpacing);
+    virtual bool refreshSizeHints(const QLayoutStyleInfo *styleInfo);
 
     virtual ~AnchorData() {}
 
@@ -180,6 +181,9 @@ struct AnchorData : public QSimplexVariable {
         hasSize = false;
     }
 
+    // Internal anchors have associated items
+    QGraphicsLayoutItem *item;
+
     // Anchor is semantically directed
     AnchorVertex *from;
     AnchorVertex *to;
@@ -205,7 +209,9 @@ struct AnchorData : public QSimplexVariable {
     uint skipInPreferred : 1;
     uint type : 2;            // either Normal, Sequential or Parallel
     uint hasSize : 1;         // if false, get size from style.
-    uint isLayoutAnchor : 1;  // if this anchor is connected to a layout 'edge'
+    uint isLayoutAnchor : 1;  // if this anchor is an internal layout anchor
+    uint isCenterAnchor : 1;
+    uint orientation : 1;
 };
 
 #ifdef QT_DEBUG
@@ -217,26 +223,20 @@ inline QString AnchorData::toString() const
 
 struct SequentialAnchorData : public AnchorData
 {
-    SequentialAnchorData() : AnchorData()
+    SequentialAnchorData(const QVector<AnchorVertex *> &vertices, const QVector<AnchorData *> &edges)
+        : AnchorData(), m_children(vertices), m_edges(edges)
     {
         type = AnchorData::Sequential;
+        orientation = m_edges.at(0)->orientation;
 #ifdef QT_DEBUG
-        name = QLatin1String("SequentialAnchorData");
+        name = QString::fromAscii("%1 -- %2").arg(vertices.first()->toString(), vertices.last()->toString());
 #endif
     }
 
     virtual void updateChildrenSizes();
-    virtual void refreshSizeHints(qreal effectiveSpacing);
+    virtual bool refreshSizeHints(const QLayoutStyleInfo *styleInfo);
 
-    void refreshSizeHints_helper(qreal effectiveSpacing, bool refreshChildren = true);
-
-    void setVertices(const QVector<AnchorVertex*> &vertices)
-    {
-        m_children = vertices;
-#ifdef QT_DEBUG
-        name = QString::fromAscii("%1 -- %2").arg(vertices.first()->toString(), vertices.last()->toString());
-#endif
-    }
+    bool refreshSizeHints_helper(const QLayoutStyleInfo *styleInfo, bool refreshChildren = true);
 
     QVector<AnchorVertex*> m_children;          // list of vertices in the sequence
     QVector<AnchorData*> m_edges;               // keep the list of edges too.
@@ -248,6 +248,7 @@ struct ParallelAnchorData : public AnchorData
         : AnchorData(), firstEdge(first), secondEdge(second)
     {
         type = AnchorData::Parallel;
+        orientation = first->orientation;
 
         // ### Those asserts force that both child anchors have the same direction,
         // but can't we simplify a pair of anchors in opposite directions?
@@ -261,9 +262,9 @@ struct ParallelAnchorData : public AnchorData
     }
 
     virtual void updateChildrenSizes();
-    virtual void refreshSizeHints(qreal effectiveSpacing);
+    virtual bool refreshSizeHints(const QLayoutStyleInfo *styleInfo);
 
-    void refreshSizeHints_helper(qreal effectiveSpacing, bool refreshChildren = true);
+    bool refreshSizeHints_helper(const QLayoutStyleInfo *styleInfo, bool refreshChildren = true);
 
     AnchorData* firstEdge;
     AnchorData* secondEdge;
@@ -423,13 +424,12 @@ public:
                               Qt::AnchorPoint &firstEdge,
                               QGraphicsLayoutItem *&secondItem,
                               Qt::AnchorPoint &secondEdge);
-    // for getting the actual spacing (will query the style if the
-    // spacing is not explicitly set).
-    qreal effectiveSpacing(Orientation orientation) const;
+
+    QLayoutStyleInfo &styleInfo() const;
 
     // Activation methods
-    void simplifyGraph(Orientation orientation);
-    bool simplifyGraphIteration(Orientation orientation);
+    bool simplifyGraph(Orientation orientation);
+    bool simplifyGraphIteration(Orientation orientation, bool *feasible);
     void restoreSimplifiedGraph(Orientation orientation);
 
     void calculateGraphs();
@@ -441,7 +441,7 @@ public:
     bool calculateNonTrunk(const QList<QSimplexConstraint *> &constraints,
                            const QList<AnchorData *> &variables);
 
-    void setAnchorSizeHintsFromItems(Orientation orientation);
+    bool refreshAllSizeHints(Orientation orientation);
     void findPaths(Orientation orientation);
     void constraintsFromPaths(Orientation orientation);
     void updateAnchorSizes(Orientation orientation);
@@ -524,10 +524,13 @@ public:
 #endif
 
     uint calculateGraphCacheDirty : 1;
+    mutable uint styleInfoDirty : 1;
+    mutable QLayoutStyleInfo cachedStyleInfo;
 
     friend class QGraphicsAnchorPrivate;
 };
 
 QT_END_NAMESPACE
+#endif //QT_NO_GRAPHICSVIEW
 
 #endif
diff --git a/src/gui/graphicsview/qgraphicsitem.cpp b/src/gui/graphicsview/qgraphicsitem.cpp
index 738c6e3..d70b039 100644
--- a/src/gui/graphicsview/qgraphicsitem.cpp
+++ b/src/gui/graphicsview/qgraphicsitem.cpp
@@ -1039,13 +1039,31 @@ void QGraphicsItemPrivate::setParentItemHelper(QGraphicsItem *newParent)
     }
 
     // Update focus scope item ptr in new scope.
-    if (newParent) {
+    QGraphicsItem *newFocusScopeItem = subFocusItem ? subFocusItem : parentFocusScopeItem;
+    if (newFocusScopeItem && newParent) {
+        if (subFocusItem) {
+            // Find the subFocusItem's topmost focus scope.
+            QGraphicsItem *ancestorScope = 0;
+            QGraphicsItem *p = subFocusItem->d_ptr->parent;
+            while (p) {
+                if (p->flags() & QGraphicsItem::ItemIsFocusScope)
+                    ancestorScope = p;
+                if (p->isPanel())
+                    break;
+                p = p->parentItem();
+            }
+            if (ancestorScope)
+                newFocusScopeItem = ancestorScope;
+        }
+
         QGraphicsItem *p = newParent;
         while (p) {
             if (p->flags() & QGraphicsItem::ItemIsFocusScope) {
-                p->d_ptr->focusScopeItem = subFocusItem ? subFocusItem : parentFocusScopeItem;
-                // ### The below line might not make sense...
-                if (subFocusItem)
+                p->d_ptr->focusScopeItem = newFocusScopeItem;
+                // Ensure the new item is no longer the subFocusItem. The
+                // only way to set focus on a child of a focus scope is
+                // by setting focus on the scope itself.
+                if (subFocusItem && !p->focusItem())
                     subFocusItem->d_ptr->clearSubFocus();
                 break;
             }
@@ -1287,6 +1305,8 @@ QGraphicsItem::QGraphicsItem(QGraphicsItemPrivate &dd, QGraphicsItem *parent,
 */
 QGraphicsItem::~QGraphicsItem()
 {
+    if (d_ptr->isObject)
+        QObjectPrivate::get(static_cast<QGraphicsObject *>(this))->wasDeleted = true;
     d_ptr->inDestructor = 1;
     d_ptr->removeExtraItemCache();
 
@@ -2982,8 +3002,11 @@ void QGraphicsItemPrivate::setFocusHelper(Qt::FocusReason focusReason, bool clim
     while (p) {
         if (p->flags() & QGraphicsItem::ItemIsFocusScope) {
             p->d_ptr->focusScopeItem = q_ptr;
-            if (!q_ptr->isActive() || !p->focusItem())
+            if (!p->focusItem()) {
+                // If you call setFocus on a child of a focus scope that
+                // doesn't currently have a focus item, then stop.
                 return;
+            }
             break;
         }
         p = p->d_ptr->parent;
@@ -4264,7 +4287,7 @@ void QGraphicsItem::stackBefore(const QGraphicsItem *sibling)
     // Only move items with the same Z value, and that need moving.
     int siblingIndex = sibling->d_ptr->siblingIndex;
     int myIndex = d_ptr->siblingIndex;
-    if (myIndex >= siblingIndex && d_ptr->z == sibling->d_ptr->z) {
+    if (myIndex >= siblingIndex) {
         siblings->move(myIndex, siblingIndex);
         // Fixup the insertion ordering.
         for (int i = 0; i < siblings->size(); ++i) {
@@ -9674,12 +9697,14 @@ bool QGraphicsTextItem::sceneEvent(QEvent *event)
         // Reset the focus widget's input context, regardless
         // of how this item gained or lost focus.
         if (QWidget *fw = qApp->focusWidget()) {
+#ifndef QT_NO_IM
             if (QInputContext *qic = fw->inputContext()) {
                 if (event->type() == QEvent::FocusIn || event->type() == QEvent::FocusOut)
                     qic->reset();
                 else
                     qic->update();
             }
+#endif //QT_NO_IM
         }
         break;
     default:
@@ -10788,8 +10813,12 @@ QDebug operator<<(QDebug debug, QGraphicsItem *item)
         return debug;
     }
 
-    debug << "QGraphicsItem(this =" << ((void*)item)
-          << ", parent =" << ((void*)item->parentItem())
+    if (QGraphicsObject *o = item->toGraphicsObject())
+        debug << o->metaObject()->className();
+    else
+        debug << "QGraphicsItem";
+    debug << "(this =" << (void*)item
+          << ", parent =" << (void*)item->parentItem()
           << ", pos =" << item->pos()
           << ", z =" << item->zValue() << ", flags = "
           << item->flags() << ")";
diff --git a/src/gui/graphicsview/qgraphicsitem_p.h b/src/gui/graphicsview/qgraphicsitem_p.h
index 183e95b..ca56c18 100644
--- a/src/gui/graphicsview/qgraphicsitem_p.h
+++ b/src/gui/graphicsview/qgraphicsitem_p.h
@@ -607,7 +607,7 @@ public:
         return item->type() == QGraphicsPixmapItem::Type
                && !(item->flags() & QGraphicsItem::ItemIsSelectable)
                && item->d_ptr->children.size() == 0;
-            //|| (item->d_ptr->isObject && qobject_cast<QFxImage *>(q_func()));
+            //|| (item->d_ptr->isObject && qobject_cast<QmlGraphicsImage *>(q_func()));
     }
 
     inline const QStyleOption *styleOption() const
diff --git a/src/gui/graphicsview/qgraphicslayout_p.h b/src/gui/graphicsview/qgraphicslayout_p.h
index 59c6dba..4aeae39 100644
--- a/src/gui/graphicsview/qgraphicslayout_p.h
+++ b/src/gui/graphicsview/qgraphicslayout_p.h
@@ -60,6 +60,8 @@
 #include "qgraphicslayout.h"
 #include "qgraphicslayoutitem_p.h"
 #include <QtGui/qstyle.h>
+#include <QtGui/qwidget.h>
+#include <QtGui/qstyleoption.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -76,6 +78,55 @@ inline bool qt_graphicsLayoutDebug()
 }
 #endif
 
+
+class QLayoutStyleInfo
+{
+public:
+    inline QLayoutStyleInfo() { invalidate(); }
+    inline QLayoutStyleInfo(QStyle *style, QWidget *widget)
+        : m_valid(true), m_style(style), m_widget(widget) 
+    {
+        Q_ASSERT(style);
+        if (widget) //###
+            m_styleOption.initFrom(widget);
+        m_defaultSpacing[0] = style->pixelMetric(QStyle::PM_LayoutHorizontalSpacing);
+        m_defaultSpacing[1] = style->pixelMetric(QStyle::PM_LayoutVerticalSpacing);
+    }
+
+    inline void invalidate() { m_valid = false; m_style = 0; m_widget = 0; }
+
+    inline QStyle *style() const { return m_style; }
+    inline QWidget *widget() const { return m_widget; }
+
+    inline bool operator==(const QLayoutStyleInfo &other)
+        { return m_style == other.m_style && m_widget == other.m_widget; }
+    inline bool operator!=(const QLayoutStyleInfo &other)
+        { return !(*this == other); }
+
+    inline void setDefaultSpacing(Qt::Orientation o, qreal spacing){
+        if (spacing >= 0)
+            m_defaultSpacing[o - 1] = spacing;
+    }
+
+    inline qreal defaultSpacing(Qt::Orientation o) const {
+        return m_defaultSpacing[o - 1];
+    }
+
+    inline qreal perItemSpacing(QSizePolicy::ControlType control1, 
+                                  QSizePolicy::ControlType control2,
+                                  Qt::Orientation orientation) const
+    {
+        Q_ASSERT(style());
+        return style()->layoutSpacing(control1, control2, orientation, &m_styleOption, widget());
+    }
+private:
+    bool m_valid;
+    QStyle *m_style;
+    QWidget *m_widget;
+    QStyleOption m_styleOption;
+    qreal m_defaultSpacing[2];
+};
+
 class Q_AUTOTEST_EXPORT QGraphicsLayoutPrivate : public QGraphicsLayoutItemPrivate
 {
     Q_DECLARE_PUBLIC(QGraphicsLayout)
diff --git a/src/gui/graphicsview/qgraphicsproxywidget.cpp b/src/gui/graphicsview/qgraphicsproxywidget.cpp
index 64c51ad..e9173a9 100644
--- a/src/gui/graphicsview/qgraphicsproxywidget.cpp
+++ b/src/gui/graphicsview/qgraphicsproxywidget.cpp
@@ -397,7 +397,7 @@ QWidget *QGraphicsProxyWidgetPrivate::findFocusChild(QWidget *child, bool next)
     do {
         if (child->isEnabled()
 	    && child->isVisibleTo(widget)
-            && (child->focusPolicy() & focus_flag == focus_flag)
+            && ((child->focusPolicy() & focus_flag) == focus_flag)
             && !(child->d_func()->extra && child->d_func()->extra->focus_proxy)) {
             return child;
         }
diff --git a/src/gui/graphicsview/qgraphicsscene.cpp b/src/gui/graphicsview/qgraphicsscene.cpp
index c459d21..f982f4b 100644
--- a/src/gui/graphicsview/qgraphicsscene.cpp
+++ b/src/gui/graphicsview/qgraphicsscene.cpp
@@ -525,6 +525,14 @@ void QGraphicsScenePrivate::removeItemHelper(QGraphicsItem *item)
 
     item->d_func()->scene = 0;
 
+    //We need to remove all children first because they might use their parent
+    //attributes (e.g. sceneTransform).
+    if (!item->d_ptr->inDestructor) {
+        // Remove all children recursively
+        for (int i = 0; i < item->d_ptr->children.size(); ++i)
+            q->removeItem(item->d_ptr->children.at(i));
+    }
+
     // Unregister focus proxy.
     item->d_ptr->resetFocusProxy();
 
@@ -571,12 +579,6 @@ void QGraphicsScenePrivate::removeItemHelper(QGraphicsItem *item)
             ++iterator;
     }
 
-    if (!item->d_ptr->inDestructor) {
-        // Remove all children recursively
-        for (int i = 0; i < item->d_ptr->children.size(); ++i)
-            q->removeItem(item->d_ptr->children.at(i));
-    }
-
     if (item->isPanel() && item->isVisible() && item->panelModality() != QGraphicsItem::NonModal)
         leaveModal(item);
 
@@ -691,6 +693,7 @@ void QGraphicsScenePrivate::setFocusItemHelper(QGraphicsItem *item,
         focusItem = 0;
         sendEvent(lastFocusItem, &event);
 
+#ifndef QT_NO_IM
         if (lastFocusItem
             && (lastFocusItem->flags() & QGraphicsItem::ItemAcceptsInputMethod)) {
             // Reset any visible preedit text
@@ -706,6 +709,7 @@ void QGraphicsScenePrivate::setFocusItemHelper(QGraphicsItem *item,
                     views.at(i)->inputContext()->reset();
             }
         }
+#endif //QT_NO_IM
     }
 
     if (item) {
@@ -4910,7 +4914,7 @@ void QGraphicsScenePrivate::processDirtyItemsRecursive(QGraphicsItem *item, bool
                     continue;
                 }
 
-                if (item->d_ptr->paintedViewBoundingRectsNeedRepaint && !paintedViewBoundingRect.isEmpty()) {
+                if (item->d_ptr->paintedViewBoundingRectsNeedRepaint) {
                     paintedViewBoundingRect.translate(viewPrivate->dirtyScrollOffset);
                     if (!viewPrivate->updateRect(paintedViewBoundingRect))
                         paintedViewBoundingRect = QRect(-1, -1, -1, -1); // Outside viewport.
diff --git a/src/gui/graphicsview/qgraphicstransform.cpp b/src/gui/graphicsview/qgraphicstransform.cpp
index e2a3f08..83bc9e1 100644
--- a/src/gui/graphicsview/qgraphicstransform.cpp
+++ b/src/gui/graphicsview/qgraphicstransform.cpp
@@ -93,8 +93,8 @@
 #include <QDebug>
 #include <QtCore/qmath.h>
 
+#ifndef QT_NO_GRAPHICSVIEW
 QT_BEGIN_NAMESPACE
-
 void QGraphicsTransformPrivate::setItem(QGraphicsItem *i)
 {
     if (item == i)
@@ -565,3 +565,4 @@ void QGraphicsRotation::applyTo(QMatrix4x4 *matrix) const
 #include "moc_qgraphicstransform.cpp"
 
 QT_END_NAMESPACE
+#endif //QT_NO_GRAPHICSVIEW
diff --git a/src/gui/graphicsview/qgraphicstransform.h b/src/gui/graphicsview/qgraphicstransform.h
index 58075aa..58e3077 100644
--- a/src/gui/graphicsview/qgraphicstransform.h
+++ b/src/gui/graphicsview/qgraphicstransform.h
@@ -47,6 +47,7 @@
 #include <QtGui/QTransform>
 #include <QtGui/QMatrix4x4>
 
+#ifndef QT_NO_GRAPHICSVIEW
 QT_BEGIN_HEADER
 
 QT_BEGIN_NAMESPACE
@@ -150,5 +151,6 @@ private:
 QT_END_NAMESPACE
 
 QT_END_HEADER
+#endif //QT_NO_GRAPHICSVIEW
 
 #endif // QFXTRANSFORM_H
diff --git a/src/gui/graphicsview/qgraphicstransform_p.h b/src/gui/graphicsview/qgraphicstransform_p.h
index 9e708b2..ddf99bb 100644
--- a/src/gui/graphicsview/qgraphicstransform_p.h
+++ b/src/gui/graphicsview/qgraphicstransform_p.h
@@ -54,7 +54,7 @@
 //
 
 #include "private/qobject_p.h"
-
+#ifndef QT_NO_GRAPHICSVIEW
 QT_BEGIN_NAMESPACE
 
 class QGraphicsItem;
@@ -73,5 +73,6 @@ public:
 };
 
 QT_END_NAMESPACE
+#endif //QT_NO_GRAPHCISVIEW
 
 #endif // QGRAPHICSTRANSFORM_P_H
diff --git a/src/gui/graphicsview/qgraphicsview.cpp b/src/gui/graphicsview/qgraphicsview.cpp
index 8945f51..c88f678 100644
--- a/src/gui/graphicsview/qgraphicsview.cpp
+++ b/src/gui/graphicsview/qgraphicsview.cpp
@@ -3325,6 +3325,14 @@ void QGraphicsView::paintEvent(QPaintEvent *event)
     if (!(d->optimizationFlags & IndirectPainting)) {
         d->scene->d_func()->drawItems(&painter, viewTransformed ? &viewTransform : 0,
                                       &d->exposedRegion, viewport());
+        // Make sure the painter's world transform is restored correctly when
+        // drawing without painter state protection (DontSavePainterState).
+        // We only change the worldTransform() so there's no need to do a full-blown
+        // save() and restore(). Also note that we don't have to do this in case of
+        // IndirectPainting (the else branch), because in that case we always save()
+        // and restore() in QGraphicsScene::drawItems().
+        if (!d->scene->d_func()->painterStateProtection)
+            painter.setWorldTransform(viewTransform);
     } else {
         // Find all exposed items
         bool allItems = false;
diff --git a/src/gui/graphicsview/qgraphicswidget.cpp b/src/gui/graphicsview/qgraphicswidget.cpp
index 35a3c13..d70a281 100644
--- a/src/gui/graphicsview/qgraphicswidget.cpp
+++ b/src/gui/graphicsview/qgraphicswidget.cpp
@@ -1352,6 +1352,8 @@ void QGraphicsWidget::changeEvent(QEvent *event)
     case QEvent::StyleChange:
         // ### Don't unset if the margins are explicitly set.
         unsetWindowFrameMargins();
+        if (d->layout)
+            d->layout->invalidate();
     case QEvent::FontChange:
         update();
         updateGeometry();
diff --git a/src/gui/graphicsview/qgridlayoutengine_p.h b/src/gui/graphicsview/qgridlayoutengine_p.h
index a42a537..ed335a8 100644
--- a/src/gui/graphicsview/qgridlayoutengine_p.h
+++ b/src/gui/graphicsview/qgridlayoutengine_p.h
@@ -59,7 +59,7 @@
 #include "qmap.h"
 #include "qpair.h"
 #include "qvector.h"
-
+#include "qgraphicslayout_p.h"
 #include <float.h>
 
 QT_BEGIN_NAMESPACE
@@ -128,29 +128,6 @@ public:
 
 };
 
-class QLayoutStyleInfo
-{
-public:
-    inline QLayoutStyleInfo() { invalidate(); }
-    inline QLayoutStyleInfo(QStyle *style, QWidget *widget)
-        : q_valid(true), q_style(style), q_widget(widget) {}
-
-    inline void invalidate() { q_valid = false; q_style = 0; q_widget = 0; }
-
-    inline QStyle *style() const { return q_style; }
-    inline QWidget *widget() const { return q_widget; }
-
-    inline bool operator==(const QLayoutStyleInfo &other)
-        { return q_style == other.q_style && q_widget == other.q_widget; }
-    inline bool operator!=(const QLayoutStyleInfo &other)
-        { return !(*this == other); }
-
-private:
-    bool q_valid;
-    QStyle *q_style;
-    QWidget *q_widget;
-};
-
 class QGridLayoutBox
 {
 public:
diff --git a/src/gui/graphicsview/qsimplex_p.cpp b/src/gui/graphicsview/qsimplex_p.cpp
index b8f8fb4..86b10b4 100644
--- a/src/gui/graphicsview/qsimplex_p.cpp
+++ b/src/gui/graphicsview/qsimplex_p.cpp
@@ -108,10 +108,8 @@ void QSimplex::clearDataStructures()
     // Constraints
     for (int i = 0; i < constraints.size(); ++i) {
         delete constraints[i]->helper.first;
-        constraints[i]->helper.first = 0;
-        constraints[i]->helper.second = 0.0;
         delete constraints[i]->artificial;
-        constraints[i]->artificial = 0;
+        delete constraints[i];
     }
     constraints.clear();
 
@@ -137,7 +135,23 @@ bool QSimplex::setConstraints(const QList<QSimplexConstraint *> newConstraints)
 
     if (newConstraints.isEmpty())
         return true;    // we are ok with no constraints
-    constraints = newConstraints;
+
+    // Make deep copy of constraints. We need this copy because we may change
+    // them in the simplification method.
+    for (int i = 0; i < newConstraints.size(); ++i) {
+        QSimplexConstraint *c = new QSimplexConstraint;
+        c->constant = newConstraints[i]->constant;
+        c->ratio = newConstraints[i]->ratio;
+        c->variables = newConstraints[i]->variables;
+        constraints << c;
+    }
+
+    // Remove constraints of type Var == K and replace them for their value.
+    if (!simplifyConstraints(&constraints)) {
+        qWarning() << "QSimplex: No feasible solution!";
+        clearDataStructures();
+        return false;
+    }
 
     ///////////////////////////////////////
     // Prepare variables and constraints //
@@ -508,11 +522,21 @@ qreal QSimplex::solver(solverFactor factor)
     // Remove old objective
     clearRow(0);
 
-    // Set new objective
+    // Set new objective in the first row of the simplex matrix
+    qreal resultOffset = 0;
     QHash<QSimplexVariable *, qreal>::const_iterator iter;
     for (iter = objective->variables.constBegin();
          iter != objective->variables.constEnd();
          ++iter) {
+
+        // Check if the variable was removed in the simplification process.
+        // If so, we save its offset to the objective function and skip adding
+        // it to the matrix.
+        if (iter.key()->index == -1) {
+            resultOffset += iter.value() * iter.key()->result;
+            continue;
+        }
+
         setValueAt(0, iter.key()->index, -1 * factor * iter.value());
     }
 
@@ -525,7 +549,9 @@ qreal QSimplex::solver(solverFactor factor)
     }
 #endif
 
-    return factor * valueAt(0, columns - 1);
+    // Return the value calculated by the simplex plus the value of the
+    // fixed variables.
+    return (factor * valueAt(0, columns - 1)) + resultOffset;
 }
 
 /*!
@@ -571,4 +597,77 @@ void QSimplex::collectResults()
     }
 }
 
+/*!
+  \internal
+
+  Looks for single-valued variables and remove them from the constraints list.
+*/
+bool QSimplex::simplifyConstraints(QList<QSimplexConstraint *> *constraints)
+{
+    QHash<QSimplexVariable *, qreal> results;   // List of single-valued variables
+    bool modified = true;                       // Any chance more optimization exists?
+
+    while (modified) {
+        modified = false;
+
+        // For all constraints
+        QList<QSimplexConstraint *>::iterator iter = constraints->begin();
+        while (iter != constraints->end()) {
+            QSimplexConstraint *c = *iter;
+            if ((c->ratio == QSimplexConstraint::Equal) && (c->variables.count() == 1)) {
+                // Check whether this is a constraint of type Var == K
+                // If so, save its value to "results".
+                QSimplexVariable *variable = c->variables.constBegin().key();
+                qreal result = c->constant / c->variables.value(variable);
+
+                results.insert(variable, result);
+                variable->result = result;
+                variable->index = -1;
+                modified = true;
+
+            }
+
+            // Replace known values among their variables
+            QHash<QSimplexVariable *, qreal>::const_iterator r;
+            for (r = results.constBegin(); r != results.constEnd(); ++r) {
+                if (c->variables.contains(r.key())) {
+                    c->constant -= r.value() * c->variables.take(r.key());
+                    modified = true;
+                }
+            }
+
+            // Keep it normalized
+            if (c->constant < 0)
+                c->invert();
+
+            if (c->variables.isEmpty()) {
+                // If constraint became empty due to substitution, delete it.
+                if (c->isSatisfied() == false)
+                    // We must ensure that the constraint soon to be deleted would not
+                    // make the problem unfeasible if left behind. If that's the case,
+                    // we return false so the simplex solver can properly report that.
+                    return false;
+
+                delete c;
+                iter = constraints->erase(iter);
+            } else {
+                ++iter;
+            }
+        }
+    }
+
+    return true;
+}
+
+void QSimplexConstraint::invert()
+{
+    constant = -constant;
+    ratio = Ratio(2 - ratio);
+
+    QHash<QSimplexVariable *, qreal>::iterator iter;
+    for (iter = variables.begin(); iter != variables.end(); ++iter) {
+        iter.value() = -iter.value();
+    }
+}
+
 QT_END_NAMESPACE
diff --git a/src/gui/graphicsview/qsimplex_p.h b/src/gui/graphicsview/qsimplex_p.h
index 51991a9..084ad7f 100644
--- a/src/gui/graphicsview/qsimplex_p.h
+++ b/src/gui/graphicsview/qsimplex_p.h
@@ -63,7 +63,7 @@ struct QSimplexVariable
     QSimplexVariable() : result(0), index(0) {}
 
     qreal result;
-    uint index;
+    int index;
 };
 
 
@@ -95,7 +95,8 @@ struct QSimplexConstraint
     QPair<QSimplexVariable *, qreal> helper;
     QSimplexVariable * artificial;
 
-#ifdef QT_DEBUG
+    void invert();
+
     bool isSatisfied() {
         qreal leftHandSide(0);
 
@@ -106,7 +107,7 @@ struct QSimplexConstraint
 
         Q_ASSERT(constant > 0 || qFuzzyCompare(1, 1 + constant));
 
-        if (qFuzzyCompare(1000 + leftHandSide, 1000 + constant))
+        if ((leftHandSide == constant) || qFuzzyCompare(1000 + leftHandSide, 1000 + constant))
             return true;
 
         switch (ratio) {
@@ -118,6 +119,30 @@ struct QSimplexConstraint
             return false;
         }
     }
+
+#ifdef QT_DEBUG
+    QString toString() {
+        QString result;
+        result += QString::fromAscii("-- QSimplexConstraint %1 --").arg(quintptr(this), 0, 16);
+
+        QHash<QSimplexVariable *, qreal>::const_iterator iter;
+        for (iter = variables.constBegin(); iter != variables.constEnd(); ++iter) {
+            result += QString::fromAscii("  %1 x %2").arg(iter.value()).arg(quintptr(iter.key()), 0, 16);
+        }
+
+        switch (ratio) {
+        case LessOrEqual:
+            result += QString::fromAscii("  (less) <= %1").arg(constant);
+            break;
+        case MoreOrEqual:
+            result += QString::fromAscii("  (more) >= %1").arg(constant);
+            break;
+        default:
+            result += QString::fromAscii("  (eqal) == %1").arg(constant);
+        }
+
+        return result;
+    }
 #endif
 };
 
@@ -129,7 +154,6 @@ public:
 
     qreal solveMin();
     qreal solveMax();
-    QList<QSimplexVariable *> constraintsVariables();
 
     bool setConstraints(const QList<QSimplexConstraint *> constraints);
     void setObjective(QSimplexConstraint *objective);
@@ -145,6 +169,7 @@ private:
     void combineRows(int toIndex, int fromIndex, qreal factor);
 
     // Simplex
+    bool simplifyConstraints(QList<QSimplexConstraint *> *constraints);
     int findPivotColumn();
     int pivotRowForColumn(int column);
     void reducedRowEchelon();
@@ -168,11 +193,6 @@ private:
     qreal *matrix;
 };
 
-inline QList<QSimplexVariable *> QSimplex::constraintsVariables()
-{
-    return variables;
-}
-
 inline qreal QSimplex::valueAt(int rowIndex, int columnIndex)
 {
     return matrix[rowIndex * columns + columnIndex];