protected override void OnDetach()
 {
     preComputeBoneBuffer = null;
     internalBoneBuffer.Detach();
     internalMTBuffer.Detach();
     base.OnDetach();
 }
 protected override void OnGeometryBufferChanged(IAttachableBufferModel buffer)
 {
     base.OnGeometryBufferChanged(buffer);
     preComputeBoneBuffer = buffer as IBoneSkinPreComputehBufferModel;
 }