Ragdoll cannot assume skeleton's rootIndex is 0

some Models have extra "joints" not part of the normal skeleton

interface/src/avatar/SkeletonModel.cpp

@@ -576,6 +576,7 @@ SkeletonRagdoll* SkeletonModel::buildRagdoll() {
     if (!_ragdoll) {
         _ragdoll = new SkeletonRagdoll(this);
         if (_enableShapes) {
+            clearShapes();
             buildShapes();
         }
     }
@@ -600,6 +601,7 @@ void SkeletonModel::buildShapes() {
     if (!_ragdoll) {
         _ragdoll = new SkeletonRagdoll(this);
     }
+    _ragdoll->setRootIndex(geometry.rootJointIndex);
     _ragdoll->initPoints();
     QVector<VerletPoint>& points = _ragdoll->getPoints();
 
@@ -614,15 +616,14 @@ void SkeletonModel::buildShapes() {
         float radius = uniformScale * joint.boneRadius;
         float halfHeight = 0.5f * uniformScale * joint.distanceToParent;
         Shape::Type type = joint.shapeType;
-        if (i == 0 || (type == Shape::CAPSULE_SHAPE && halfHeight < EPSILON)) {
+        int parentIndex = joint.parentIndex;
+        if (parentIndex == -1 || radius < EPSILON) {
+            type = Shape::UNKNOWN_SHAPE;
+        } else if (type == Shape::CAPSULE_SHAPE && halfHeight < EPSILON) {
             // this shape is forced to be a sphere
             type = Shape::SPHERE_SHAPE;
         }
-        if (radius < EPSILON) {
-            type = Shape::UNKNOWN_SHAPE;
-        }
         Shape* shape = NULL;
-        int parentIndex = joint.parentIndex;
         if (type == Shape::SPHERE_SHAPE) {
             shape = new VerletSphereShape(radius, &(points[i]));
             shape->setEntity(this);
@@ -637,18 +638,16 @@ void SkeletonModel::buildShapes() {
             points[i].setMass(mass);
             totalMass += mass;
         } 
-        if (parentIndex != -1) {
+        if (shape && parentIndex != -1) {
             // always disable collisions between joint and its parent
-            if (shape) {
-                disableCollisions(i, parentIndex);
-            }
+            disableCollisions(i, parentIndex);
         } 
         _shapes.push_back(shape);
     }
 
     // set the mass of the root
     if (numStates > 0) {
-        points[0].setMass(totalMass);
+        points[_ragdoll->getRootIndex()].setMass(totalMass);
     }
 
     // This method moves the shapes to their default positions in Model frame.

interface/src/avatar/SkeletonRagdoll.cpp

@@ -36,8 +36,9 @@ void SkeletonRagdoll::stepForward(float deltaTime) {
 
 void SkeletonRagdoll::slamPointPositions() {
     QVector<JointState>& jointStates = _model->getJointStates();
-    int numStates = jointStates.size();
-    for (int i = 0; i < numStates; ++i) {
+    const int numPoints = _points.size();
+    assert(numPoints == jointStates.size());
+    for (int i = _rootIndex; i < numPoints; ++i) {
         _points[i].initPosition(jointStates.at(i).getPosition());
     }
 }
@@ -49,8 +50,7 @@ void SkeletonRagdoll::initPoints() {
 
     initTransform();
     // one point for each joint
-    QVector<JointState>& jointStates = _model->getJointStates();
-    int numStates = jointStates.size();
+    int numStates = _model->getJointStates().size();
     _points.fill(VerletPoint(), numStates);
     slamPointPositions();
 }
@@ -67,7 +67,7 @@ void SkeletonRagdoll::buildConstraints() {
     float minBone = FLT_MAX;
     float maxBone = -FLT_MAX;
     QMultiMap<int, int> families;
-    for (int i = 0; i < numPoints; ++i) {
+    for (int i = _rootIndex; i < numPoints; ++i) {
         const JointState& state = jointStates.at(i);
         int parentIndex = state.getParentIndex();
         if (parentIndex != -1) {
@@ -105,7 +105,7 @@ void SkeletonRagdoll::buildConstraints() {
     float MAX_STRENGTH = 0.6f;
     float MIN_STRENGTH = 0.05f;
     // each joint gets a MuscleConstraint to its parent
-    for (int i = 1; i < numPoints; ++i) {
+    for (int i = _rootIndex + 1; i < numPoints; ++i) {
         const JointState& state = jointStates.at(i);
         int p = state.getParentIndex();
         if (p == -1) {

libraries/shared/src/Ragdoll.cpp

@@ -20,7 +20,7 @@
 #include "SharedUtil.h" // for EPSILON
 
 Ragdoll::Ragdoll() : _massScale(1.0f), _translation(0.0f), _translationInSimulationFrame(0.0f), 
-        _accumulatedMovement(0.0f), _simulation(NULL) {
+        _rootIndex(0), _accumulatedMovement(0.0f), _simulation(NULL) {
 }
 
 Ragdoll::~Ragdoll() {
@@ -35,7 +35,7 @@ void Ragdoll::stepForward(float deltaTime) {
         updateSimulationTransforms(_translation - _simulation->getTranslation(), _rotation);
     }
     int numPoints = _points.size();
-    for (int i = 0; i < numPoints; ++i) {
+    for (int i = _rootIndex; i < numPoints; ++i) {
         _points[i].integrateForward();
     }
 }
@@ -77,7 +77,9 @@ void Ragdoll::initTransform() {
 }
 
 void Ragdoll::setTransform(const glm::vec3& translation, const glm::quat& rotation) {
-    _translation = translation;
+    if (translation != _translation) {
+        _translation = translation;
+    }
     _rotation = rotation;
 }
 
@@ -95,7 +97,7 @@ void Ragdoll::updateSimulationTransforms(const glm::vec3& translation, const glm
 
     // apply the deltas to all ragdollPoints
     int numPoints = _points.size();
-    for (int i = 0; i < numPoints; ++i) {
+    for (int i = _rootIndex; i < numPoints; ++i) {
         _points[i].move(deltaPosition, deltaRotation, _translationInSimulationFrame);
     }
 
@@ -111,7 +113,7 @@ void Ragdoll::setMassScale(float scale) {
     if (scale != _massScale) {
         float rescale = scale / _massScale;
         int numPoints = _points.size();
-        for (int i = 0; i < numPoints; ++i) {
+        for (int i = _rootIndex; i < numPoints; ++i) {
             _points[i].setMass(rescale * _points[i].getMass());
         }
         _massScale = scale;
@@ -122,10 +124,10 @@ void Ragdoll::removeRootOffset(bool accumulateMovement) {
     const int numPoints = _points.size();
     if (numPoints > 0) {
         // shift all points so that the root aligns with the the ragdoll's position in the simulation
-        glm::vec3 offset = _translationInSimulationFrame - _points[0]._position;
+        glm::vec3 offset = _translationInSimulationFrame - _points[_rootIndex]._position;
         float offsetLength = glm::length(offset);
         if (offsetLength > EPSILON) {
-            for (int i = 0; i < numPoints; ++i) {
+            for (int i = _rootIndex; i < numPoints; ++i) {
                 _points[i].shift(offset);
             }
             const float MIN_ROOT_OFFSET = 0.02f;

libraries/shared/src/Ragdoll.h

@@ -52,6 +52,10 @@ public:
     void setMassScale(float scale);
     float getMassScale() const { return _massScale; }
 
+    // the ragdoll's rootIndex (within a Model's joints) is not always zero so must be settable
+    void setRootIndex(int index) { _rootIndex = index; }
+    int getRootIndex() const { return _rootIndex; }
+
     void clearConstraintsAndPoints();
     virtual void initPoints() = 0;
     virtual void buildConstraints() = 0;
@@ -66,6 +70,7 @@ protected:
     glm::quat _rotation; // world-frame
     glm::vec3 _translationInSimulationFrame;
     glm::quat _rotationInSimulationFrame;
+    int _rootIndex;
 
     QVector<VerletPoint> _points;
     QVector<DistanceConstraint*> _boneConstraints;