Merge pull request #1281 from AnalyticalGraphicsInc/matrixOpt

Translation-Quaternion Rotation-Scale

Source/Core/Matrix4.js

@@ -263,9 +263,51 @@ define([
             result = new Matrix4();
         }
 
-        scratchTrsRotation = Matrix3.fromQuaternion(rotation, scratchTrsRotation);
-        result = Matrix4.fromRotationTranslation(scratchTrsRotation, translation, result);
-        return Matrix4.multiplyByScale(result, scale, result);
+        var scaleX = scale.x;
+        var scaleY = scale.y;
+        var scaleZ = scale.z;
+
+        var x2 = rotation.x * rotation.x;
+        var xy = rotation.x * rotation.y;
+        var xz = rotation.x * rotation.z;
+        var xw = rotation.x * rotation.w;
+        var y2 = rotation.y * rotation.y;
+        var yz = rotation.y * rotation.z;
+        var yw = rotation.y * rotation.w;
+        var z2 = rotation.z * rotation.z;
+        var zw = rotation.z * rotation.w;
+        var w2 = rotation.w * rotation.w;
+
+        var m00 = x2 - y2 - z2 + w2;
+        var m01 = 2.0 * (xy - zw);
+        var m02 = 2.0 * (xz + yw);
+
+        var m10 = 2.0 * (xy + zw);
+        var m11 = -x2 + y2 - z2 + w2;
+        var m12 = 2.0 * (yz - xw);
+
+        var m20 = 2.0 * (xz - yw);
+        var m21 = 2.0 * (yz + xw);
+        var m22 = -x2 - y2 + z2 + w2;
+
+        result[0]  = m00 * scaleX;
+        result[1]  = m10 * scaleX;
+        result[2]  = m20 * scaleX;
+        result[3]  = 0.0;
+        result[4]  = m01 * scaleY;
+        result[5]  = m11 * scaleY;
+        result[6]  = m21 * scaleY;
+        result[7]  = 0.0;
+        result[8]  = m02 * scaleZ;
+        result[9]  = m12 * scaleZ;
+        result[10] = m22 * scaleZ;
+        result[11] = 0.0;
+        result[12] = translation.x;
+        result[13] = translation.y;
+        result[14] = translation.z;
+        result[15] = 1.0;
+
+        return result;
     };
 
     /**