Adding avatar body-body collisions to prevent near-clipping.

interface/src/avatar/MyAvatar.cpp

@@ -225,8 +225,6 @@ void MyAvatar::simulate(float deltaTime) {
             updateCollisionWithVoxels(deltaTime, radius);
         }
         if (_collisionFlags & COLLISION_GROUP_AVATARS) {
-            // Note, hand-vs-avatar collisions are done elsewhere
-            // This is where we avatar-vs-avatar bounding capsule
             updateCollisionWithAvatars(deltaTime);
         }
     }
@@ -974,7 +972,43 @@ void MyAvatar::updateCollisionSound(const glm::vec3 &penetration, float deltaTim
     }
 }
 
-const float DEFAULT_HAND_RADIUS = 0.1f;
+bool findAvatarAvatarPenetration(const glm::vec3 positionA, float radiusA, float heightA,
+        const glm::vec3 positionB, float radiusB, float heightB, glm::vec3& penetration) {
+    glm::vec3 positionBA = positionB - positionA;
+    float xzDistance = sqrt(positionBA.x * positionBA.x + positionBA.z * positionBA.z);
+    if (xzDistance < (radiusA + radiusB)) {
+        float yDistance = fabs(positionBA.y);
+        float halfHeights = 0.5 * (heightA + heightB);
+        if (yDistance < halfHeights) {
+            // cylinders collide
+            if (xzDistance > 0.f) {
+                positionBA.y = 0.f;
+                // note, penetration should point from A into B
+                penetration = positionBA * ((radiusA + radiusB - xzDistance) / xzDistance);
+                return true;
+            } else {
+                // exactly coaxial -- we'll return false for this case
+                return false;
+            }
+        } else if (yDistance < halfHeights + radiusA + radiusB) {
+            // caps collide
+            if (positionBA.y < 0.f) {
+                // A is above B
+                positionBA.y += halfHeights;
+                float BA = glm::length(positionBA);
+                penetration = positionBA * (radiusA + radiusB - BA) / BA;
+                return true;
+            } else {
+                // A is below B
+                positionBA.y -= halfHeights;
+                float BA = glm::length(positionBA);
+                penetration = positionBA * (radiusA + radiusB - BA) / BA;
+                return true;
+            }
+        }
+    }
+    return false;
+}
 
 void MyAvatar::updateCollisionWithAvatars(float deltaTime) {
     //  Reset detector for nearest avatar
@@ -984,7 +1018,14 @@ void MyAvatar::updateCollisionWithAvatars(float deltaTime) {
         // no need to compute a bunch of stuff if we have one or fewer avatars
         return;
     }
-    float myRadius = getHeight();
+    float myBoundingRadius = 0.5f * getHeight();
+
+    // HACK: body-body collision uses two coaxial capsules with axes parallel to y-axis
+    // TODO: make the collision work without assuming avatar orientation
+    Extents myStaticExtents = _skeletonModel.getStaticExtents();
+    glm::vec3 staticScale = myStaticExtents.maximum - myStaticExtents.minimum;
+    float myCapsuleRadius = 0.25f * (staticScale.x + staticScale.z);
+    float myCapsuleHeight = staticScale.y;
 
     CollisionInfo collisionInfo;
     foreach (const AvatarSharedPointer& avatarPointer, avatars) {
@@ -997,9 +1038,20 @@ void MyAvatar::updateCollisionWithAvatars(float deltaTime) {
         if (_distanceToNearestAvatar > distance) {
             _distanceToNearestAvatar = distance;
         }
-        float theirRadius = avatar->getHeight();
+        float theirBoundingRadius = 0.5f * avatar->getHeight();
-        if (distance < myRadius + theirRadius) {
+        if (distance < myBoundingRadius + theirBoundingRadius) {
-            // TODO: Andrew to make avatar-avatar capsule collisions work here
+            Extents theirStaticExtents = _skeletonModel.getStaticExtents();
+            glm::vec3 staticScale = theirStaticExtents.maximum - theirStaticExtents.minimum;
+            float theirCapsuleRadius = 0.25f * (staticScale.x + staticScale.z);
+            float theirCapsuleHeight = staticScale.y;
+
+            glm::vec3 penetration(0.f);
+            if (findAvatarAvatarPenetration(_position, myCapsuleRadius, myCapsuleHeight,
+                avatar->getPosition(), theirCapsuleRadius, theirCapsuleHeight, penetration)) {
+                // move the avatar out by half the penetration
+                setPosition(_position - 0.5f * penetration);
+                glm::vec3 pushOut = 0.5f * penetration;
+            }
         }
     }
 }

interface/src/renderer/FBXReader.cpp

@@ -1268,6 +1268,8 @@ FBXGeometry extractFBXGeometry(const FBXNode& node, const QVariantHash& mapping)
 
     geometry.bindExtents.minimum = glm::vec3(FLT_MAX, FLT_MAX, FLT_MAX);
     geometry.bindExtents.maximum = glm::vec3(-FLT_MAX, -FLT_MAX, -FLT_MAX);
+    geometry.staticExtents.minimum = glm::vec3(FLT_MAX, FLT_MAX, FLT_MAX);
+    geometry.staticExtents.maximum = glm::vec3(-FLT_MAX, -FLT_MAX, -FLT_MAX);
     
     QVariantHash springs = mapping.value("spring").toHash();
     QVariant defaultSpring = springs.value("default");
@@ -1424,6 +1426,8 @@ FBXGeometry extractFBXGeometry(const FBXNode& node, const QVariantHash& mapping)
                         boneDirection /= boneLength;
                     }
                 }
+                bool jointIsStatic = joint.freeLineage.isEmpty();
+                glm::vec3 jointTranslation = extractTranslation(geometry.offset * joint.bindTransform);
                 float radiusScale = extractUniformScale(joint.transform * fbxCluster.inverseBindMatrix);
                 float totalWeight = 0.0f;
                 for (int j = 0; j < cluster.indices.size(); j++) {
@@ -1441,6 +1445,11 @@ FBXGeometry extractFBXGeometry(const FBXNode& node, const QVariantHash& mapping)
                                 joint.boneRadius = glm::max(joint.boneRadius, radiusScale * glm::distance(
                                     vertex, boneEnd + boneDirection * proj));
                             }
+                            if (jointIsStatic) {
+                                // expand the extents of static (nonmovable) joints
+                                geometry.staticExtents.minimum = glm::min(geometry.staticExtents.minimum, vertex + jointTranslation);
+                                geometry.staticExtents.maximum = glm::max(geometry.staticExtents.maximum, vertex + jointTranslation);
+                            }
                         }
 
                         // look for an unused slot in the weights vector

interface/src/renderer/FBXReader.h

@@ -159,6 +159,7 @@ public:
     glm::vec3 neckPivot;
     
     Extents bindExtents;
+    Extents staticExtents;
     
     QVector<FBXAttachment> attachments;
 };

interface/src/renderer/Model.cpp

@@ -305,6 +305,15 @@ Extents Model::getBindExtents() const {
     return scaledExtents;
 }
 
+Extents Model::getStaticExtents() const {
+    if (!isActive()) {
+        return Extents();
+    }
+    const Extents& staticExtents = _geometry->getFBXGeometry().staticExtents;
+    Extents scaledExtents = { staticExtents.minimum * _scale, staticExtents.maximum * _scale };
+    return scaledExtents;
+}
+
 int Model::getParentJointIndex(int jointIndex) const {
     return (isActive() && jointIndex != -1) ? _geometry->getFBXGeometry().joints.at(jointIndex).parentIndex : -1;
 }

interface/src/renderer/Model.h

@@ -66,6 +66,9 @@ public:
     
     /// Returns the extents of the model in its bind pose.
     Extents getBindExtents() const;
+
+    /// Returns the extents of the unmovable joints of the model.
+    Extents getStaticExtents() const;
     
     /// Returns a reference to the shared geometry.
     const QSharedPointer<NetworkGeometry>& getGeometry() const { return _geometry; }