code: func (c *Callbacks) OnCSVCMsg_BSPDecal(fn func(*dota.CSVCMsg_BSPDecal) error) {
  	c.onCSVCMsg_BSPDecal = append(c.onCSVCMsg_BSPDecal, fn)
  }
docs: // OnCSVCMsg_BSPDecal registers a callback for SVC_Messages_svc_BSPDecal