Add function to find set of leaf blend node ids that need evaluating

We should only evaluate the clips that are actually dependencies of
the blend tree being evaluated given its current state. At present
this will simply be the set of all leaf nodes in the blend tree but
in the future when we support generalised lerp nodes etc, this will
yield the subset needed for the current state.

This involved adding support for pre-order traversal of the blend tree.
As a result, extended the visitor to work with both pre and post orders
and for all nodes or only the dependencies.

Note that we return the ids of the blend tree nodes, not the ids of
the clips themsevles. This is so we can then index the results by
blend node id in a later commit.

Change-Id: Ia13fe90ec3090306c1e8ade316ce0540f36a67fd
Reviewed-by: Mike Krus <mike.krus@kdab.com>

1 files changed, 69 insertions, 0 deletions

diff --git a/tests/auto/animation/animationutils/tst_animationutils.cpp b/tests/auto/animation/animationutils/tst_animationutils.cpp
index 7c95b2117..534eb1678 100644
--- a/tests/auto/animation/animationutils/tst_animationutils.cpp
+++ b/tests/auto/animation/animationutils/tst_animationutils.cpp
@@ -31,7 +31,9 @@
 #include <Qt3DAnimation/private/animationutils_p.h>
 #include <Qt3DAnimation/private/channelmapper_p.h>
 #include <Qt3DAnimation/private/channelmapping_p.h>
+#include <Qt3DAnimation/private/clipblendvalue_p.h>
 #include <Qt3DAnimation/private/handler_p.h>
+#include <Qt3DAnimation/private/lerpclipblend_p.h>
 #include <Qt3DAnimation/private/managers_p.h>
 #include <Qt3DCore/qpropertyupdatedchange.h>
 #include <QtGui/qvector2d.h>
@@ -123,6 +125,28 @@ public:
         return animator;
     }
 
+    LerpClipBlend *createLerpClipBlend(Handler *handler)
+    {
+        auto lerpId = Qt3DCore::QNodeId::createId();
+        LerpClipBlend *lerp = new LerpClipBlend();
+        setPeerId(lerp, lerpId);
+        lerp->setClipBlendNodeManager(handler->clipBlendNodeManager());
+        lerp->setHandler(handler);
+        handler->clipBlendNodeManager()->appendNode(lerpId, lerp);
+        return lerp;
+    }
+
+    ClipBlendValue *createClipBlendValue(Handler *handler)
+    {
+        auto valueId = Qt3DCore::QNodeId::createId();
+        ClipBlendValue *value = new ClipBlendValue();
+        setPeerId(value, valueId);
+        value->setClipBlendNodeManager(handler->clipBlendNodeManager());
+        value->setHandler(handler);
+        handler->clipBlendNodeManager()->appendNode(valueId, value);
+        return value;
+    }
+
 private Q_SLOTS:
     void checkBuildPropertyMappings_data()
     {
@@ -1481,6 +1505,51 @@ private Q_SLOTS:
         // Cleanup
         delete handler;
     }
+
+    void checkGatherValueNodesToEvaluate_data()
+    {
+        QTest::addColumn<Handler *>("handler");
+        QTest::addColumn<Qt3DCore::QNodeId>("blendTreeRootId");
+        QTest::addColumn<QVector<Qt3DCore::QNodeId>>("expectedIds");
+
+        {
+            Handler *handler = new Handler;
+
+            const auto lerp = createLerpClipBlend(handler);
+            const auto value1 = createClipBlendValue(handler);
+            const auto clip1Id = Qt3DCore::QNodeId::createId();
+            value1->setClipId(clip1Id);
+            lerp->setStartClipId(value1->peerId());
+
+            const auto value2 = createClipBlendValue(handler);
+            const auto clip2Id = Qt3DCore::QNodeId::createId();
+            value2->setClipId(clip2Id);
+            lerp->setEndClipId(value2->peerId());
+
+            QVector<Qt3DCore::QNodeId> expectedIds = { value1->peerId(), value2->peerId() };
+
+            QTest::newRow("simple lerp") << handler << lerp->peerId() << expectedIds;
+        }
+    }
+
+    void checkGatherValueNodesToEvaluate()
+    {
+        // GIVEN
+        QFETCH(Handler *, handler);
+        QFETCH(Qt3DCore::QNodeId, blendTreeRootId);
+        QFETCH(QVector<Qt3DCore::QNodeId>, expectedIds);
+
+        // WHEN
+        QVector<Qt3DCore::QNodeId> actualIds = gatherValueNodesToEvaluate(handler, blendTreeRootId);
+
+        // THEN
+        QCOMPARE(actualIds.size(), expectedIds.size());
+        for (int i = 0; i < actualIds.size(); ++i)
+            QCOMPARE(actualIds[i], expectedIds[i]);
+
+        // Cleanup
+        delete handler;
+    }
 };
 
 QTEST_MAIN(tst_AnimationUtils)