Correct rotationAxis for frame and hand, fixes #191

leapmotion · Nov 14, 2014 · 17631ed · 17631ed
1 parent 5f9c18c
commit 17631ed
Show file tree

Hide file tree

Showing 2 changed files with 15 additions and 7 deletions.
diff --git a/lib/frame.js b/lib/frame.js
@@ -351,10 +351,14 @@ Frame.prototype.rotationAngle = function(sinceFrame, axis) {
  */
 Frame.prototype.rotationAxis = function(sinceFrame) {
   if (!this.valid || !sinceFrame.valid) return vec3.create();
+
+  var rotation = Leap.mat3.create();
+  Leap.mat3.multiply(rotation, this._rotation, sinceFrame._rotation);
+
   return vec3.normalize(vec3.create(), [
-    this._rotation[7] - sinceFrame._rotation[5],
-    this._rotation[2] - sinceFrame._rotation[6],
-    this._rotation[3] - sinceFrame._rotation[1]
+    rotation[7] - rotation[5],
+    rotation[2] - rotation[6],
+    rotation[3] - rotation[1]
   ]);
 }
 

diff --git a/lib/hand.js b/lib/hand.js
@@ -275,12 +275,16 @@ Hand.prototype.rotationAxis = function(sinceFrame) {
   if (!this.valid || !sinceFrame.valid) return vec3.create();
   var sinceHand = sinceFrame.hand(this.id);
   if (!sinceHand.valid) return vec3.create();
+
+  var rotation = Leap.mat3.create();
+  Leap.mat3.multiply(rotation, this._rotation, sinceHand._rotation);
+
   return vec3.normalize(vec3.create(), [
-    this._rotation[7] - sinceHand._rotation[5],
-    this._rotation[2] - sinceHand._rotation[6],
-    this._rotation[3] - sinceHand._rotation[1]
+    rotation[7] - rotation[5],
+    rotation[2] - rotation[6],
+    rotation[3] - rotation[1]
   ]);
-}
+};
 
 /**
  * The transform matrix expressing the rotation derived from the change in