code: function(shape){
          var remove=shape;
          if(remove.parent!=this)return;
          var prev=remove.prev;
          var next=remove.next;
          if(prev!=null)prev.next=next;
          if(next!=null)next.prev=prev;
          if(this.shapes==remove)this.shapes=next;
          remove.prev=null;
          remove.next=null;
          remove.parent=null;
          if(this.parent)this.parent.removeShape(remove);
          this.numShapes--;
      }
docs: I will delete the shape from the rigid body.
  If you delete a shape, please call the setupMass method to step up to the start of the next.
  @param   shape shape to Delete