> For the complete documentation index, see [llms.txt](https://docs.mapbox.com/mapbox-gl-js/ja/llms.txt)
# Add custom fog to a map
This example uses [`setFog`](https://docs.mapbox.com/mapbox-gl-js/ja/api/map/#map#setfog) to add a custom atmosphere effect to a map. It transitions between night and day to change the mood of the environment.
> Example code:
**JavaScript**
```html
Add custom fog to a map
```
**React**
```jsx
import React, { useEffect, useRef } from 'react';
import * as mapboxgl from 'mapbox-gl/esm';
import 'mapbox-gl/dist/mapbox-gl.css';
const MapboxExample = () => {
const mapContainerRef = useRef();
const mapRef = useRef();
useEffect(() => {
mapRef.current = new mapboxgl.Map({
// TO MAKE THE MAP APPEAR YOU MUST
// ADD YOUR ACCESS TOKEN FROM
// https://account.mapbox.com
accessToken: 'YOUR_MAPBOX_ACCESS_TOKEN',
container: 'map',
zoom: 13,
center: [6.6301, 45.35625],
pitch: 80,
bearing: 160,
interactive: false,
style: 'mapbox://styles/mapbox/standard-satellite'
});
mapRef.current.once('style.load').then(() => {
mapRef.current.setFog({
range: [-1, 2],
'horizon-blend': 0.3,
color: 'white',
'high-color': '#add8e6',
'space-color': '#d8f2ff',
'star-intensity': 0.0
});
mapRef.current.addSource('mapbox-dem', {
type: 'raster-dem',
url: 'mapbox://mapbox.terrain-rgb',
tileSize: 512,
maxzoom: 14
});
mapRef.current.setTerrain({
source: 'mapbox-dem',
exaggeration: 1.5
});
mapRef.current.once('idle').then(() => {
let lastTime = 0.0;
let animationTime = 0.0;
let cycleTime = 0.0;
let night = true;
const initialBearing = mapRef.current.getBearing();
function frame(time) {
const elapsedTime = (time - lastTime) / 1000.0;
animationTime += elapsedTime;
cycleTime += elapsedTime;
if (cycleTime >= 10.0) {
if (night) {
// night fog styling
mapRef.current.setFog({
range: [-1, 2],
'horizon-blend': 0.3,
color: '#242B4B',
'high-color': '#161B36',
'space-color': '#0B1026',
'star-intensity': 0.8
});
} else {
// day fog styling
mapRef.current.setFog({
range: [-1, 2],
'horizon-blend': 0.3,
color: 'white',
'high-color': '#add8e6',
'space-color': '#d8f2ff',
'star-intensity': 0.0
});
}
night = !night;
cycleTime = 0.0;
}
const rotation = initialBearing + animationTime * 2.0;
mapRef.current.setBearing(rotation % 360);
lastTime = time;
window.requestAnimationFrame(frame);
}
window.requestAnimationFrame(frame);
});
});
return () => mapRef.current.remove();
}, []);
return ;
};
export default MapboxExample;
```
## More Examples
View some examples of our other style features here:
> **Related content (example): [Rain Example Mapbox GL JS](https://docs.mapbox.com/mapbox-gl-js/example/rain/)**
>
> This example adds a rain effect to the map by setting the style's rain property. You can adjust the intensity, direction, color, and more of the precipitation presented on screen.
> **Related content (example): [Snow Example Mapbox GL JS](https://docs.mapbox.com/mapbox-gl-js/example/snow/)**
>
> This example adds a snow effect to the map by setting the style's snow property. You can adjust the intensity, direction, color, and more of the precipitation presented on screen.