code: function () {
          var position = this.position;
          var rotation = this.rotation;
          var scale = this.scale;
  
          if (this.transformNeedsUpdate()) {
              var m = this.localTransform.array;
  
              // Transform order, scale->rotation->position
              mat4.fromRotationTranslation(m, rotation.array, position.array);
  
              mat4.scale(m, m, scale.array);
  
              rotation._dirty = false;
              scale._dirty = false;
              position._dirty = false;
  
              this._needsUpdateWorldTransform = true;
          }
      }
docs: Update local transform from SRT
  Notice that local transform will not be updated if _dirty mark of position, rotation, scale is all false