Add function to recursively calculate duration of a blend tree

The resulting duration is independent of which animators the blend
tree is associated with so this can be implemented as a simple set
of virtual functions in the concrete classes.

The value node simply returns the duration of the contained clip; the
additive node returns the duration of the base node; and the lerp node
lerps the durations of the start and end nodes.

Change-Id: Ib6edea3fa495885493fa72d44437fea5a8c5a446
Reviewed-by: Paul Lemire <paul.lemire@kdab.com>
Reviewed-by: Mike Krus <mike.krus@kdab.com>

7 files changed, 34 insertions, 5 deletions

diff --git a/src/animation/backend/additiveclipblend_p.h b/src/animation/backend/additiveclipblend_p.h
index d8f3f36c9..8ac53d364 100644
--- a/src/animation/backend/additiveclipblend_p.h
+++ b/src/animation/backend/additiveclipblend_p.h
@@ -79,6 +79,13 @@ public:
         return { m_baseClipId, m_additiveClipId };
     }
 
+    inline double duration() const Q_DECL_OVERRIDE
+    {
+        ClipBlendNode *node = clipBlendNodeManager()->lookupNode(m_baseClipId);
+        Q_ASSERT(node);
+        return node->duration();
+    }
+
 private:
     void initializeFromPeer(const Qt3DCore::QNodeCreatedChangeBasePtr &change) Q_DECL_FINAL;
 
diff --git a/src/animation/backend/clipblendnode.cpp b/src/animation/backend/clipblendnode.cpp
index 745a7a27b..18d57b0c7 100644
--- a/src/animation/backend/clipblendnode.cpp
+++ b/src/animation/backend/clipblendnode.cpp
@@ -106,10 +106,7 @@ void ClipBlendNode::setClipBlendNodeManager(ClipBlendNodeManager *manager)
     m_manager = manager;
 }
 
-ClipBlendNodeManager *ClipBlendNode::clipBlendNodeManager() const
-{
-    return m_manager;
-}
+
 
 void ClipBlendNode::initializeFromPeer(const Qt3DCore::QNodeCreatedChangeBasePtr &change)
 {
diff --git a/src/animation/backend/clipblendnode_p.h b/src/animation/backend/clipblendnode_p.h
index 538009dc3..4784c81a7 100644
--- a/src/animation/backend/clipblendnode_p.h
+++ b/src/animation/backend/clipblendnode_p.h
@@ -73,8 +73,8 @@ public:
     };
 
     void setClipBlendNodeManager(ClipBlendNodeManager *manager);
+    inline ClipBlendNodeManager *clipBlendNodeManager() const { return m_manager; }
 
-    ClipBlendNodeManager *clipBlendNodeManager() const;
     BlendType blendType() const;
     Qt3DCore::QNodeId parentId() const;
     Qt3DCore::QNodeIdVector childrenIds() const;
@@ -86,6 +86,7 @@ public:
     ClipResults clipResults(Qt3DCore::QNodeId animatorId) const;
 
     virtual QVector<Qt3DCore::QNodeId> dependencyIds() const = 0;
+    virtual double duration() const = 0;
 
 protected:
     explicit ClipBlendNode(BlendType blendType);
diff --git a/src/animation/backend/clipblendvalue.cpp b/src/animation/backend/clipblendvalue.cpp
index 0607340c7..b8216ec38 100644
--- a/src/animation/backend/clipblendvalue.cpp
+++ b/src/animation/backend/clipblendvalue.cpp
@@ -81,6 +81,15 @@ float ClipBlendValue::blend(float value1, float value2) const
     return 0.0f;
 }
 
+double ClipBlendValue::duration() const
+{
+    if (m_clipId.isNull())
+        return 0.0;
+    AnimationClipLoader *clip = m_handler->animationClipLoaderManager()->lookupResource(m_clipId);
+    Q_ASSERT(clip);
+    return clip->duration();
+}
+
 } // namespace Animation
 } // namespace Qt3DAnimation
 
diff --git a/src/animation/backend/clipblendvalue_p.h b/src/animation/backend/clipblendvalue_p.h
index ea5141553..a50bd8e9a 100644
--- a/src/animation/backend/clipblendvalue_p.h
+++ b/src/animation/backend/clipblendvalue_p.h
@@ -72,6 +72,8 @@ public:
         return { m_clipId };
     }
 
+    double duration() const Q_DECL_OVERRIDE;
+
 private:
     void initializeFromPeer(const Qt3DCore::QNodeCreatedChangeBasePtr &change) Q_DECL_FINAL;
 
diff --git a/src/animation/backend/lerpclipblend.cpp b/src/animation/backend/lerpclipblend.cpp
index 7e10a5174..7b1efbf50 100644
--- a/src/animation/backend/lerpclipblend.cpp
+++ b/src/animation/backend/lerpclipblend.cpp
@@ -85,6 +85,17 @@ void LerpClipBlend::initializeFromPeer(const Qt3DCore::QNodeCreatedChangeBasePtr
     m_blendFactor = cloneData.blendFactor;
 }
 
+double LerpClipBlend::duration() const
+{
+    ClipBlendNode *startNode = clipBlendNodeManager()->lookupNode(m_startClipId);
+    const double startNodeDuration = startNode ? startNode->duration() : 0.0;
+
+    ClipBlendNode *endNode = clipBlendNodeManager()->lookupNode(m_endClipId);
+    const double endNodeDuration = endNode ? endNode->duration() : 0.0;
+
+    return blend(startNodeDuration, endNodeDuration);
+}
+
 } // Animation
 
 } // Qt3DAnimation
diff --git a/src/animation/backend/lerpclipblend_p.h b/src/animation/backend/lerpclipblend_p.h
index e3a2b4c7e..36b2c17e3 100644
--- a/src/animation/backend/lerpclipblend_p.h
+++ b/src/animation/backend/lerpclipblend_p.h
@@ -79,6 +79,8 @@ public:
         return { m_startClipId, m_endClipId };
     }
 
+    double duration() const Q_DECL_OVERRIDE;
+
 private:
     void initializeFromPeer(const Qt3DCore::QNodeCreatedChangeBasePtr &change) Q_DECL_FINAL;