QGAL: Support for out-of-order parallel anchors

Now parallel anchors account for the fact they may be composed of
anchors with different directions. We arbitrarily set the direction
of the parallel anchor to be the same direction as the first child.

The methods refreshSizeHints and updateChildren were updated to
support this situation.

Signed-off-by: Eduardo M. Fleury <eduardo.fleury@openbossa.org>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>

1 files changed, 5 insertions, 4 deletions

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.h b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
index 1e11ee2..8d77b1a 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.h
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
@@ -256,10 +256,11 @@ struct ParallelAnchorData : public AnchorData
         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?
-        Q_ASSERT(first->from == second->from);
-        Q_ASSERT(first->to == second->to);
+        // This assert whether the child anchors share their vertices
+        Q_ASSERT(((first->from == second->from) && (first->to == second->to)) ||
+                 ((first->from == second->to) && (first->to == second->from)));
+
+        // We arbitrarily choose the direction of the first child as "our" direction
         from = first->from;
         to = first->to;
 #ifdef QT_DEBUG