Preupdate not working offline

Hi Gabby,

Below code is working in cesium portal.
But if i take it offline, then it is throwing an error :

"Uncaught TypeError: Cannot read property 'addEventListener' of undefined"

Code :

viewer.scene.preUpdate.addEventListener(function(scene, time) {
      particleSystem.modelMatrix = computeModelMatrix(entity, time);

      // Account for any changes to the emitter model matrix.
      // particleSystem.emitterModelMatrix = computeEmitterModelMatrix();

      // Spin the emitter if enabled.
      if (viewModel.spin) {
        viewModel.heading += 1.0;
        viewModel.pitch += 1.0;
        viewModel.roll += 1.0;
      }
    });

Please help

What Cesium version are you using? It may be outdated.