Fix invoking anim events for multi blend animations

Source/Engine/Animations/Graph/AnimGraph.h

@@ -874,6 +874,7 @@ private:
 
     int32 GetRootNodeIndex(Animation* anim);
     void ExtractRootMotion(const Animation::NodeToChannel* mapping, int32 rootNodeIndex, Animation* anim, float pos, float prevPos, Transform& rootNode, RootMotionData& rootMotion);
+    void ProcessAnimEvents(AnimGraphNode* node, bool loop, float length, float startTimePos, float oldTimePos, float animPos, float animPrevPos, Animation* anim, float speed);
     Variant SampleAnimation(AnimGraphNode* node, bool loop, float length, float startTimePos, float prevTimePos, float& newTimePos, Animation* anim, float speed);
     Variant SampleAnimationsWithBlend(AnimGraphNode* node, bool loop, float length, float startTimePos, float prevTimePos, float& newTimePos, Animation* animA, Animation* animB, float speedA, float speedB, float alpha);
     Variant SampleAnimationsWithBlend(AnimGraphNode* node, bool loop, float length, float startTimePos, float prevTimePos, float& newTimePos, Animation* animA, Animation* animB, Animation* animC, float speedA, float speedB, float speedC, float alphaA, float alphaB, float alphaC);

Source/Engine/Animations/Graph/AnimGroup.Animation.cpp

@@ -88,6 +88,82 @@ void AnimGraphExecutor::ExtractRootMotion(const Animation::NodeToChannel* mappin
     rootNode = refPose;
 }
 
+void AnimGraphExecutor::ProcessAnimEvents(AnimGraphNode* node, bool loop, float length, float startTimePos, float oldTimePos, float animPos, float animPrevPos, Animation* anim, float speed)
+{
+    if (anim->Events.Count() == 0)
+        return;
+    ANIM_GRAPH_PROFILE_EVENT("Events");
+    auto& context = Context.Get();
+    float eventTimeMin = animPrevPos;
+    float eventTimeMax = animPos;
+    if (loop)
+    {
+        // Check if animation looped
+        const float posNotLooped = startTimePos + oldTimePos;
+        if (posNotLooped < 0.0f || posNotLooped > length)
+        {
+            if (context.DeltaTime * speed < 0)
+            {
+                // Playback backwards
+                Swap(eventTimeMin, eventTimeMax);
+            }
+        }
+    }
+    const float eventTime = animPos / static_cast<float>(anim->Data.FramesPerSecond);
+    const float eventDeltaTime = (animPos - animPrevPos) / static_cast<float>(anim->Data.FramesPerSecond);
+    for (const auto& track : anim->Events)
+    {
+        for (const auto& k : track.Second.GetKeyframes())
+        {
+            if (!k.Value.Instance)
+                continue;
+            const float duration = k.Value.Duration > 1 ? k.Value.Duration : 0.0f;
+            if (k.Time <= eventTimeMax && eventTimeMin <= k.Time + duration)
+            {
+                int32 stateIndex = -1;
+                if (duration > 1)
+                {
+                    // Begin for continuous event
+                    for (stateIndex = 0; stateIndex < context.Data->Events.Count(); stateIndex++)
+                    {
+                        const auto& e = context.Data->Events[stateIndex];
+                        if (e.Instance == k.Value.Instance && e.Node == node)
+                            break;
+                    }
+                    if (stateIndex == context.Data->Events.Count())
+                    {
+                        auto& e = context.Data->Events.AddOne();
+                        e.Instance = k.Value.Instance;
+                        e.Anim = anim;
+                        e.Node = node;
+                        ASSERT(k.Value.Instance->Is<AnimContinuousEvent>());
+                        ((AnimContinuousEvent*)k.Value.Instance)->OnBegin((AnimatedModel*)context.Data->Object, anim, eventTime, eventDeltaTime);
+                    }
+                }
+
+                // Event
+                k.Value.Instance->OnEvent((AnimatedModel*)context.Data->Object, anim, eventTime, eventDeltaTime);
+                if (stateIndex != -1)
+                    context.Data->Events[stateIndex].Hit = true;
+            }
+            else if (duration > 1)
+            {
+                // End for continuous event
+                for (int32 i = 0; i < context.Data->Events.Count(); i++)
+                {
+                    const auto& e = context.Data->Events[i];
+                    if (e.Instance == k.Value.Instance && e.Node == node)
+                    {
+                        ((AnimContinuousEvent*)k.Value.Instance)->OnEnd((AnimatedModel*)context.Data->Object, anim, eventTime, eventDeltaTime);
+                        context.Data->Events.RemoveAt(i);
+                        break;
+                    }
+                }
+            }
+        }
+    }
+}
+
 float GetAnimPos(float& timePos, float startTimePos, bool loop, float length)
 {
     // Apply animation offset and looping to calculate the animation sampling position within [0;length]
@@ -184,79 +260,7 @@ Variant AnimGraphExecutor::SampleAnimation(AnimGraphNode* node, bool loop, float
     }
 
     // Collect events
-    if (anim->Events.Count() != 0)
+    ProcessAnimEvents(node, loop, length, startTimePos, oldTimePos, animPos, animPrevPos, anim, speed);
-    {
-        ANIM_GRAPH_PROFILE_EVENT("Events");
-        auto& context = Context.Get();
-        float eventTimeMin = animPrevPos;
-        float eventTimeMax = animPos;
-        if (loop)
-        {
-            // Check if animation looped
-            const float posNotLooped = startTimePos + oldTimePos;
-            if (posNotLooped < 0.0f || posNotLooped > length)
-            {
-                if (context.DeltaTime * speed < 0)
-                {
-                    // Playback backwards
-                    Swap(eventTimeMin, eventTimeMax);
-                }
-            }
-        }
-        const float eventTime = animPos / static_cast<float>(anim->Data.FramesPerSecond);
-        const float eventDeltaTime = (animPos - animPrevPos) / static_cast<float>(anim->Data.FramesPerSecond);
-        for (const auto& track : anim->Events)
-        {
-            for (const auto& k : track.Second.GetKeyframes())
-            {
-                if (!k.Value.Instance)
-                    continue;
-                const float duration = k.Value.Duration > 1 ? k.Value.Duration : 0.0f;
-                if (k.Time <= eventTimeMax && eventTimeMin <= k.Time + duration)
-                {
-                    int32 stateIndex = -1;
-                    if (duration > 1)
-                    {
-                        // Begin for continuous event
-                        for (stateIndex = 0; stateIndex < context.Data->Events.Count(); stateIndex++)
-                        {
-                            const auto& e = context.Data->Events[stateIndex];
-                            if (e.Instance == k.Value.Instance && e.Node == node)
-                                break;
-                        }
-                        if (stateIndex == context.Data->Events.Count())
-                        {
-                            auto& e = context.Data->Events.AddOne();
-                            e.Instance = k.Value.Instance;
-                            e.Anim = anim;
-                            e.Node = node;
-                            ASSERT(k.Value.Instance->Is<AnimContinuousEvent>());
-                            ((AnimContinuousEvent*)k.Value.Instance)->OnBegin((AnimatedModel*)context.Data->Object, anim, eventTime, eventDeltaTime);
-                        }
-                    }
-
-                    // Event
-                    k.Value.Instance->OnEvent((AnimatedModel*)context.Data->Object, anim, eventTime, eventDeltaTime);
-                    if (stateIndex != -1)
-                        context.Data->Events[stateIndex].Hit = true;
-                }
-                else if (duration > 1)
-                {
-                    // End for continuous event
-                    for (int32 i = 0; i < context.Data->Events.Count(); i++)
-                    {
-                        const auto& e = context.Data->Events[i];
-                        if (e.Instance == k.Value.Instance && e.Node == node)
-                        {
-                            ((AnimContinuousEvent*)k.Value.Instance)->OnEnd((AnimatedModel*)context.Data->Object, anim, eventTime, eventDeltaTime);
-                            context.Data->Events.RemoveAt(i);
-                            break;
-                        }
-                    }
-                }
-            }
-        }
-    }
 
     return nodes;
 }
@@ -267,6 +271,7 @@ Variant AnimGraphExecutor::SampleAnimationsWithBlend(AnimGraphNode* node, bool l
     if (animA == nullptr || !animA->IsLoaded() ||
         animB == nullptr || !animB->IsLoaded())
         return Value::Null;
+    const float oldTimePos = prevTimePos;
 
     // Calculate actual time position within the animation node (defined by length and loop mode)
     const float pos = GetAnimPos(newTimePos, startTimePos, loop, length);
@@ -327,6 +332,12 @@ Variant AnimGraphExecutor::SampleAnimationsWithBlend(AnimGraphNode* node, bool l
         RootMotionData::Lerp(rootMotionA, rootMotionB, alpha, nodes->RootMotion);
     }
 
+    // Collect events
+    if (alpha > 0.5f)
+        ProcessAnimEvents(node, loop, length, startTimePos, oldTimePos, animPosB, animPrevPosB, animB, speedB);
+    else
+        ProcessAnimEvents(node, loop, length, startTimePos, oldTimePos, animPosA, animPrevPosA, animA, speedA);
+
     return nodes;
 }
 
@@ -337,6 +348,7 @@ Variant AnimGraphExecutor::SampleAnimationsWithBlend(AnimGraphNode* node, bool l
         animB == nullptr || !animB->IsLoaded() ||
         animC == nullptr || !animC->IsLoaded())
         return Value::Null;
+    const float oldTimePos = prevTimePos;
 
     // Calculate actual time position within the animation node (defined by length and loop mode)
     const float pos = GetAnimPos(newTimePos, startTimePos, loop, length);
@@ -436,6 +448,14 @@ Variant AnimGraphExecutor::SampleAnimationsWithBlend(AnimGraphNode* node, bool l
         BlendAdditiveWeightedRotation(nodes->RootMotion.Rotation, rootMotionB.Rotation, alphaC);
     }
 
+    // Collect events
+    if (alphaC > 0.5f)
+        ProcessAnimEvents(node, loop, length, startTimePos, oldTimePos, animPosC, animPrevPosC, animC, speedC);
+    else if (alphaB > 0.5f)
+        ProcessAnimEvents(node, loop, length, startTimePos, oldTimePos, animPosB, animPrevPosB, animB, speedB);
+    else
+        ProcessAnimEvents(node, loop, length, startTimePos, oldTimePos, animPosA, animPrevPosA, animA, speedA);
+
     return nodes;
 }