From bd6f00e707c4df82b8b9c26db4f2297f4c3bb919 Mon Sep 17 00:00:00 2001
From: Andrew Meadows <andrew@highfidelity.io>
Date: Wed, 1 Aug 2018 11:58:52 -0700
Subject: [PATCH] eliminate angular dynamics of other-avatars

---
 interface/src/avatar/AvatarMotionState.cpp | 12 ++++++++++++
 interface/src/avatar/AvatarMotionState.h   |  1 +
 libraries/physics/src/ObjectMotionState.h  |  2 +-
 3 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/interface/src/avatar/AvatarMotionState.cpp b/interface/src/avatar/AvatarMotionState.cpp
index 298701ca5d..bff5233f1d 100644
--- a/interface/src/avatar/AvatarMotionState.cpp
+++ b/interface/src/avatar/AvatarMotionState.cpp
@@ -96,6 +96,10 @@ void AvatarMotionState::setWorldTransform(const btTransform& worldTrans) {
         btVector3 velocity = glmToBullet(getObjectLinearVelocity()) + (1.0f / SPRING_TIMESCALE) * offsetToTarget;
         _body->setLinearVelocity(velocity);
         _body->setAngularVelocity(glmToBullet(getObjectAngularVelocity()));
+        // slam its rotation
+        btTransform newTransform = worldTrans;
+        newTransform.setRotation(glmToBullet(getObjectRotation()));
+        _body->setWorldTransform(newTransform);
     }
 }
 
@@ -191,6 +195,14 @@ void AvatarMotionState::cacheShapeDiameter() {
     }
 }
 
+void AvatarMotionState::setRigidBody(btRigidBody* body) {
+    ObjectMotionState::setRigidBody(body);
+    if (_body) {
+        // remove angular dynamics from this body
+        _body->setAngularFactor(0.0f);
+    }
+}
+
 void AvatarMotionState::setShape(const btCollisionShape* shape) {
     cacheShapeDiameter();
     ObjectMotionState::setShape(shape);
diff --git a/interface/src/avatar/AvatarMotionState.h b/interface/src/avatar/AvatarMotionState.h
index 62fbc566f3..a458704b1a 100644
--- a/interface/src/avatar/AvatarMotionState.h
+++ b/interface/src/avatar/AvatarMotionState.h
@@ -74,6 +74,7 @@ public:
     friend class Avatar;
 
 protected:
+    void setRigidBody(btRigidBody* body) override;
     void setShape(const btCollisionShape* shape) override;
     void cacheShapeDiameter();
 
diff --git a/libraries/physics/src/ObjectMotionState.h b/libraries/physics/src/ObjectMotionState.h
index 269117b28c..74173c3f47 100644
--- a/libraries/physics/src/ObjectMotionState.h
+++ b/libraries/physics/src/ObjectMotionState.h
@@ -175,7 +175,7 @@ protected:
     virtual void setMotionType(PhysicsMotionType motionType);
     void updateCCDConfiguration();
 
-    void setRigidBody(btRigidBody* body);
+    virtual void setRigidBody(btRigidBody* body);
     virtual void setShape(const btCollisionShape* shape);
 
     MotionStateType _type { MOTIONSTATE_TYPE_INVALID }; // type of MotionState