mrdoob/three.js — pull request #3307 by WestLangley (2013-04-12 01:39:07+00:00)
Title: Cleaned up ArrowHelper

1. Made `ArrowHelper` quaternion-based -- it's faster
2. Made judicious use of `matrixAutoUpdate = false` :-)
3. Used closures where appropriate
5. Continued the assumption that direction vectors are assumed to be normalized