From 8bc92144453e486b614662daea5df829aa8cf416 Mon Sep 17 00:00:00 2001
From: barnold1953 <brb555@utk.edu>
Date: Thu, 10 Jul 2014 14:37:04 -0700
Subject: [PATCH] Added helper scaling function to Avatar.

---
 interface/src/avatar/Avatar.cpp | 5 +++++
 interface/src/avatar/Avatar.h   | 4 ++++
 interface/src/avatar/Hand.cpp   | 4 ++--
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/interface/src/avatar/Avatar.cpp b/interface/src/avatar/Avatar.cpp
index 3221e75e56..2ebbd55c85 100644
--- a/interface/src/avatar/Avatar.cpp
+++ b/interface/src/avatar/Avatar.cpp
@@ -970,6 +970,11 @@ glm::quat Avatar::getJointCombinedRotation(const QString& name) const {
     return rotation;
 }
 
+void Avatar::scaleVectorRelativeToPosition(glm::vec3 &positionToScale) const {
+    //Scale a world space vector as if it was relative to the position
+    positionToScale = _position + _scale * (positionToScale - _position);
+}
+
 void Avatar::setFaceModelURL(const QUrl& faceModelURL) {
     AvatarData::setFaceModelURL(faceModelURL);
     const QUrl DEFAULT_FACE_MODEL_URL = QUrl::fromLocalFile(Application::resourcesPath() + "meshes/defaultAvatar_head.fst");
diff --git a/interface/src/avatar/Avatar.h b/interface/src/avatar/Avatar.h
index 8c14fc9ed0..6fb7991c3c 100755
--- a/interface/src/avatar/Avatar.h
+++ b/interface/src/avatar/Avatar.h
@@ -152,6 +152,10 @@ public:
     
     glm::vec3 getAcceleration() const { return _acceleration; }
     glm::vec3 getAngularVelocity() const { return _angularVelocity; }
+
+    /// Scales a world space position vector relative to the avatar position and scale
+    /// \param vector position to be scaled. Will store the result
+    void scaleVectorRelativeToPosition(glm::vec3 &positionToScale) const;
     
 public slots:
     void updateCollisionGroups();
diff --git a/interface/src/avatar/Hand.cpp b/interface/src/avatar/Hand.cpp
index aae9cb0a29..08e1cf83df 100644
--- a/interface/src/avatar/Hand.cpp
+++ b/interface/src/avatar/Hand.cpp
@@ -170,8 +170,8 @@ void Hand::renderHandTargets(bool isMine) {
             glm::vec3 root = palm.getPosition();
 
             //Scale the positions based on avatar scale
-            tip = myAvatar->getPosition() + avatarScale * (tip - myAvatar->getPosition());
-            root = myAvatar->getPosition() + avatarScale * (root - myAvatar->getPosition());
+            myAvatar->scaleVectorRelativeToPosition(tip);
+            myAvatar->scaleVectorRelativeToPosition(root);
 
             Avatar::renderJointConnectingCone(root, tip, PALM_FINGER_ROD_RADIUS, PALM_FINGER_ROD_RADIUS);
             //  Render sphere at palm/finger root