xrf.frag.rot = function(v, opts){
  let { mesh, model, camera, scene, renderer, THREE} = opts
  console.log("   └ setting camera rotation to "+v.string)
  camera.rotation.set( 
    v.x * Math.PI / 180,
    v.y * Math.PI / 180,
    v.z * Math.PI / 180
  )
  camera.updateMatrixWorld()
}