Prototype blend. Just equal weighting for now.

libraries/animation/src/AnimationHandle.cpp

@@ -176,7 +176,9 @@ void AnimationHandle::applyFrame(float frameIndex) {
                                                      safeMix(floorFrame.rotations.at(i),
                                                              ceilFrame.rotations.at(i),
                                                              frameFraction),
-                                                     _priority);
+                                                     _priority,
+                                                     false,
+                                                     _mix);
         }
     }
 }

libraries/animation/src/AnimationHandle.h

@@ -63,6 +63,7 @@ public:
 
     void setPriority(float priority);
     float getPriority() const { return _priority; }
+    void setMix(float mix) { _mix = mix; }
 
     void setMaskedJoints(const QStringList& maskedJoints);
     const QStringList& getMaskedJoints() const { return _maskedJoints; }
@@ -119,6 +120,7 @@ private:
     QString _role;
     QUrl _url;
     float _priority;
+    float _mix;
 
     QStringList _maskedJoints;
     QVector<int> _jointMappings;

libraries/animation/src/JointState.cpp

@@ -232,12 +232,13 @@ glm::quat JointState::computeVisibleParentRotation() const {
     return _visibleRotation * glm::inverse(_fbxJoint->preRotation * _visibleRotationInConstrainedFrame * _fbxJoint->postRotation);
 }
 
-void JointState::setRotationInConstrainedFrame(glm::quat targetRotation, float priority, bool constrain) {
+void JointState::setRotationInConstrainedFrame(glm::quat targetRotation, float priority, bool constrain, float mix) {
     if (priority >= _animationPriority || _animationPriority == 0.0f) {
         if (constrain && _constraint) {
             _constraint->softClamp(targetRotation, _rotationInConstrainedFrame, 0.5f);
         }
-        setRotationInConstrainedFrameInternal(targetRotation);
+        auto rotation = (mix == 1.0f) ? targetRotation : safeMix(getRotationInConstrainedFrame(), targetRotation, mix);
+        setRotationInConstrainedFrameInternal(rotation);
         _animationPriority = priority;
     }
 }

libraries/animation/src/JointState.h

@@ -84,7 +84,7 @@ public:
     /// NOTE: the JointState's model-frame transform/rotation are NOT updated!
     void setRotationInBindFrame(const glm::quat& rotation, float priority, bool constrain = false);
 
-    void setRotationInConstrainedFrame(glm::quat targetRotation, float priority, bool constrain = false);
+    void setRotationInConstrainedFrame(glm::quat targetRotation, float priority, bool constrain = false, float mix = 1.0f);
     void setVisibleRotationInConstrainedFrame(const glm::quat& targetRotation);
     const glm::quat& getRotationInConstrainedFrame() const { return _rotationInConstrainedFrame; }
     const glm::quat& getVisibleRotationInConstrainedFrame() const { return _visibleRotationInConstrainedFrame; }

libraries/animation/src/Rig.cpp

@@ -390,7 +390,10 @@ void Rig::computeMotionAnimationState(float deltaTime, const glm::vec3& worldPos
 }
 
 void Rig::updateAnimations(float deltaTime, glm::mat4 parentTransform) {
+    int nAnimationsSoFar = 0;
     foreach (const AnimationHandlePointer& handle, _runningAnimations) {
+        handle->setMix(1.0f / ++nAnimationsSoFar);
+        handle->setPriority(1.0);
         handle->simulate(deltaTime);
     }
 
@@ -640,13 +643,13 @@ glm::vec3 Rig::getJointDefaultTranslationInConstrainedFrame(int jointIndex) {
     return _jointStates[jointIndex].getDefaultTranslationInConstrainedFrame();
 }
 
-glm::quat Rig::setJointRotationInConstrainedFrame(int jointIndex, glm::quat targetRotation, float priority, bool constrain) {
+glm::quat Rig::setJointRotationInConstrainedFrame(int jointIndex, glm::quat targetRotation, float priority, bool constrain, float mix) {
     glm::quat endRotation;
     if (jointIndex == -1 || _jointStates.isEmpty()) {
         return endRotation;
     }
     JointState& state = _jointStates[jointIndex];
-    state.setRotationInConstrainedFrame(targetRotation, priority, constrain);
+    state.setRotationInConstrainedFrame(targetRotation, priority, constrain, mix);
     endRotation = state.getRotationInConstrainedFrame();
     return endRotation;
 }

libraries/animation/src/Rig.h

@@ -139,7 +139,7 @@ public:
     glm::quat setJointRotationInBindFrame(int jointIndex, const glm::quat& rotation, float priority, bool constrain = false);
     glm::vec3 getJointDefaultTranslationInConstrainedFrame(int jointIndex);
     glm::quat setJointRotationInConstrainedFrame(int jointIndex, glm::quat targetRotation,
-                                                 float priority, bool constrain = false);
+                                                 float priority, bool constrain = false, float mix = 1.0f);
     glm::quat getJointDefaultRotationInParentFrame(int jointIndex);
     void updateVisibleJointStates();