[Vuejs]-How update vue variable if API variable changed?

It seems Pano2VR has a varchanged_VARNAME event that occurs for variable changes. You could hook into that to update Vue:

const app = new Vue ({
  mounted() {
    pano.on('varchanged_vue_text', () => {
      this.dude = pano.getVariableValue('vue_text')
    })
  }
})