Mapbox GL JS
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Style Specification
Getting started (1)Display a mapStyles (11)Add a default markerAdd an animated icon to the mapAdd a generated icon to the mapGenerate and add a missing icon to the mapAdd a stretchable image to the mapAdd an icon to the mapDisplay a map with a custom styleRender world copiesDisplay a satellite mapChange a map's styleDisplay a mapLayers (40)Display buildings in 3DExtrude polygons for 3D indoor mappingAdd a 3D modelAdd an animated icon to the mapAdd a generated icon to the mapGenerate and add a missing icon to the mapAdd a stretchable image to the mapAdd an icon to the mapAdjust a layer's opacityAnimate a lineAnimate a series of imagesAnimate a pointChange building color based on zoom levelChange the case of labelsDisplay HTML clusters with custom propertiesCreate and style clustersChange a layer's color with buttonsAdd a custom style layerStyle circles with a data-driven propertyStyle lines with a data-driven propertyDisplay and style rich text labelsAdd a pattern to a polygonAdd a new layer below labelsAdd a GeoJSON lineDraw GeoJSON pointsAdd a GeoJSON polygonCreate a heatmap layerAdd hillshadingAdd an imageDisplay line that crosses 180th meridianCreate a gradient line using an expressionAdd multiple geometries from one GeoJSON sourceStyle ocean depth dataShow and hide layersChange worldview of administrative boundariesUpdate a choropleth layer by zoom levelVariable label placementAdd a videoVisualize population densityUse a fallback imageSources (16)Animate a lineAnimate a series of imagesAnimate a pointAdd a canvas sourceJoin local JSON data with vector tile geometriesAdd hillshadingAdd an imageDisplay line that crosses 180th meridianAdd live realtime dataUpdate a feature in realtimeAdd a raster tile sourceAdd a third party vector tile sourceCreate a time sliderAdd a vector tile sourceAdd a videoAdd a WMS sourceUser interaction (27)Adjust a layer's opacityCustomize camera animationsCenter the map on a clicked symbolChange a layer's color with buttonsAnimate 3D buildings based on ambient soundsDisable map rotationCreate a draggable MarkerCreate a draggable pointFilter features within map viewFilter symbols by text inputFilter symbols by toggling a listCreate a hover effectDisplay a non-interactive mapChange a map's languageMeasure distancesGet coordinates of the mouse pointerHighlight features containing similar dataSelect features around a clicked pointGet features under the mouse pointerRestrict map panning to an areaChange a map's styleCreate a time sliderToggle interactionsChange worldview of administrative boundariesUpdate a choropleth layer by zoom levelHighlight features within a bounding boxFit to the bounds of a LineStringCamera (13)Animate map camera around a pointAnimate a point along a routeCustomize camera animationsCenter the map on a clicked symbolFit a map to a bounding boxSlowly fly to a locationFly to a locationNavigate the map with game-like controlsJump to a series of locationsOffset the vanishing point using paddingPlay map locations as a slideshowFly to a location based on scroll positionSet pitch and bearingControls and overlays (17)Animate a markerChange the default position for attributionAdd custom icons with MarkersDisable scroll zoomView a fullscreen mapLocate the userSwipe between mapsDisplay driving directionsShow drawn polygon areaAdd a geocoderAdd a marker using a place nameDisplay map navigation controlsShow polygon information on clickDisplay a popup on clickDisplay a popup on hoverDisplay a popupAttach a popup to a marker instanceGeocoder (10)Supplement forward geocoding search results from another data sourceAccept coordinates as input to a geocoderLimit geocoder results to a named regionUse a custom render function with a geocoderUse the geocoder without a mapPlace the geocoder input outside the mapUse a custom camera animation with a geocoderLocalize the geocoder to a given languageAdd a geocoderSet a point after Geocoder resultBrowser support (1)Check if Mapbox GL JS is supportedInternationalization support (2)Use locally generated ideographsAdd support for right-to-left scripts

Create a gradient line using an expression

Use the line-gradient paint property and an expression to visualize distance from the starting point of a line.

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>Create a gradient line using an expression</title>
<meta name="viewport" content="initial-scale=1,maximum-scale=1,user-scalable=no" />
<script src="https://api.mapbox.com/mapbox-gl-js/v1.12.0/mapbox-gl.js"></script>
<link href="https://api.mapbox.com/mapbox-gl-js/v1.12.0/mapbox-gl.css" rel="stylesheet" />
<style>
	body { margin: 0; padding: 0; }
	#map { position: absolute; top: 0; bottom: 0; width: 100%; }
</style>
</head>
<body>
<div id="map"></div>
 
<script>
	// TO MAKE THE MAP APPEAR YOU MUST
	// ADD YOUR ACCESS TOKEN FROM
	// https://account.mapbox.com
	mapboxgl.accessToken = '<your access token here>';
var map = (window.map = new mapboxgl.Map({
container: 'map',
style: 'mapbox://styles/mapbox/light-v10',
center: [-77.035, 38.875],
zoom: 12
}));
 
var geojson = {
'type': 'FeatureCollection',
'features': [
{
'type': 'Feature',
'properties': {},
'geometry': {
'coordinates': [
[-77.044211, 38.852924],
[-77.045659, 38.860158],
[-77.044232, 38.862326],
[-77.040879, 38.865454],
[-77.039936, 38.867698],
[-77.040338, 38.86943],
[-77.04264, 38.872528],
[-77.03696, 38.878424],
[-77.032309, 38.87937],
[-77.030056, 38.880945],
[-77.027645, 38.881779],
[-77.026946, 38.882645],
[-77.026942, 38.885502],
[-77.028054, 38.887449],
[-77.02806, 38.892088],
[-77.03364, 38.892108],
[-77.033643, 38.899926]
],
'type': 'LineString'
}
}
]
};
 
map.on('load', function () {
// 'line-gradient' can only be used with GeoJSON sources
// and the source must have the 'lineMetrics' option set to true
map.addSource('line', {
type: 'geojson',
lineMetrics: true,
data: geojson
});
 
// the layer must be of type 'line'
map.addLayer({
type: 'line',
source: 'line',
id: 'line',
paint: {
'line-color': 'red',
'line-width': 14,
// 'line-gradient' must be specified using an expression
// with the special 'line-progress' property
'line-gradient': [
'interpolate',
['linear'],
['line-progress'],
0,
'blue',
0.1,
'royalblue',
0.3,
'cyan',
0.5,
'lime',
0.7,
'yellow',
1,
'red'
]
},
layout: {
'line-cap': 'round',
'line-join': 'round'
}
});
});
</script>
 
</body>
</html>
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