code: function(v) {
      var m = this.m;
      return new Vector(
        m[0] * v.x + m[1] * v.y + m[2] * v.z,
        m[4] * v.x + m[5] * v.y + m[6] * v.z,
        m[8] * v.x + m[9] * v.y + m[10] * v.z
      );
    }
docs: ### .transformPoint(vector)  Transforms the vector as a vector with a w coordinate of 0. This means translations will have no effect, for example.