Blur+Hue over UI

This example is only available in gl-react-native. Implementing it in gl-react-dom would be possible if reimplementing the whole UI in a Canvas. However, we can't do it by just using DOM like we can easily use Views in gl-react-native.



    <HueRotate hue={-switch1 + 2 * switch2 + 4 * switch3}>

      <View style={{ width: 256, height: 160, padding: 10 }}>
        <SliderIOS style={{ height: 80 }} maximumValue={2} onValueChange={factor => this.setState({ factor })} />
      <View style={{ height: 60, flexDirection: "row", alignItems: "center" }}>
        <SwitchIOS style={{flex:1}} value={switch1} onValueChange={switch1 => this.setState({ switch1 })} />
        <SwitchIOS style={{flex:1}} value={switch2} onValueChange={switch2 => this.setState({ switch2 })} />
        <SwitchIOS style={{flex:1}} value={switch3} onValueChange={switch3 => this.setState({ switch3 })} />
      <ProgressViewIOS progress={factor} style={{height: 10, marginTop: 8, flex:1}} />


autoRedraw, eventsThrough and visibleContent

These 3 props are essential to make this example work:

  • autoRedraw makes the view continously re-render (and in an efficient way, the render loop is implemented in Objective-C. in gl-react-dom context, it is also a bit more performant). In our example, we need to do that because we can't observe UI animation changes (like when I smoothly move the switch) so we just assume the UI always changes and needs a redraw.
  • eventsThrough allows to make touch events going through the GL view: we don't want our effect layer to respond for those events but the underlying content with the slider and switches.
  • visibleContent prevents the content (our view with the slider and switches) to be hidden. When used with eventsThrough, it makes the content intercepting the events.