code: function (value) {
                  var previousNeedCube = this.needCube();
                  this._direction = value;
                  if (this.needCube() !== previousNeedCube && this._shadowGenerator) {
                      this._shadowGenerator.recreateShadowMap();
                  }
              }
docs: In case of direction provided, the shadow will not use a cube texture but simulate a spot shadow as a fallback