anchor.diff:    @override
     bool init() {
       if (super.init()) {
  -      initGroupingBehavior(this);
  +//      initGroupingBehavior(this);
         
         return true;
       }
  
positive.code:     
      Ranger.RectangleApplyAffineTransform(accumBox, transform);
  
      if (children != null) {
        // Iterate children collecting Bounding Boxes
        for(PolygonNode child in children) {
          if (child.visible) {
            // Recurse into children
            Ranger.MutableRectangle<double> childBox = child._calcAABBOfChild(transform); // A pooled rectangle
            
            // Accumulate bounds. Union child bbox.
            accumBox.union(childBox);
            
            // Return bbox back to pool for next child.
            childBox.moveToPool();
          }
        }
      }
      
      transform.moveToPool();
      
  
negative.code:     
      Ranger.RectApplyAffineTransformTo(polygon.aabbox, accumBox, transform);
  
  //    if (children != null) {
  //      // Iterate children collecting Bounding Boxes
  //      for(PolygonNode child in children) {
  //        if (child.visible) {
  //          // Recurse into children
  //          Ranger.MutableRectangle<double> childBox = child._calcParentAABB(transform);
  //          
  //          // Accumulate bounds. Union child bbox.
  //          accumBox.union(childBox);
  //          
  //          // Return bbox back to pool for next child.
  //          childBox.moveToPool();
  //        }
  //      }
  //    }
      
      transform.moveToPool();
      
  