anchor.diff:  
     //todo: distanceToPoint
   
  -  BoundingSphere get boundingSphere => new BoundingSphere(size.length * 0.5, center);
  +  BoundingSphere get boundingSphere => new BoundingSphere(radius: size.length * 0.5, center: center);
   
     intersect( BoundingBox box ) {
       Vector3.max(_aabb3.min, box.min, _aabb3.min );
  
positive.code:   }
  
    BoundingBox.fromCenterAndSize(Vector3 center, Vector3 size) {
      var halfSize = new Vector3.copy(size).multiplyScalar(0.5);
      _aabb3 = new Aabb3.minMax(new Vector3.copy(center).sub(haldSize), new Vector3.copy(center).add(haldSize));
    }
  
    BoundingBox.fromObject(Object3D object) {
  
negative.code: 
    expandByVector(Vector3 vector) => _aabb3.copyMinMax(_aabb3.min.sub(vector), _aabb3.max.add(vector));
  
    expandByScalar(num scalar) => _aabb3.copyMinMax(_aabb3.min - new Vector3.all(scalar), _aabb3.max + new Vector3.all(scalar));
  
    bool containsPoint(Vector3 point) => _aabb3.containsVector3(point);
  
  