Learn how to calculate the area that can be reached in a given driving time from a location.
A service area, also known as an isochrone, is a polygon that represents the area that can be reached when driving or walking on a street network. The area that can be reached is restricted by either time or distance. To calculate service areas, you can use the routing service. You provide a start location (facilities), one or more time or distance values, and a spatial reference. Once processed, the service returns the service areas that can be reached.
In this tutorial, you create and display five, ten, and fifteen minute drive time service areas when the map is clicked. You use data-driven styling to give each polygon a different shade of blue.
Prerequisites
An ArcGIS Location Platform or ArcGIS Online account.
Steps
Get the starter app
Select a type of authentication below and follow the steps to create a new application.
Set up authentication
Create developer credentials in your portal for the type of authentication you selected.
Set developer credentials
Use the API key or OAuth developer credentials created in the previous step in your application.
Get a Cesium ion access token
All Cesium applications must use an access token provided through Cesium ion. This token allows you to access assets such as Cesium World Terrain in your application.
-
Go to your Cesium ion dashboard to generate an access token. Copy the key to your clipboard.
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Create a
cesium
variable and replaceAccess Token YOUR
with the access token you copied from the Cesium ion dashboard._CESIUM _ACCESS _TOKEN Use dark colors for code blocks <script> /* Use for API key authentication */ const accessToken = "YOUR_ACCESS_TOKEN"; // or /* Use for user authentication */ // const session = await arcgisRest.ArcGISIdentityManager.beginOAuth2({ // clientId: "YOUR_CLIENT_ID", // Your client ID from OAuth credentials // redirectUri: "YOUR_REDIRECT_URL", // The redirect URL registered in your OAuth credentials // portal: "YOUR_PORTAL_URL" // Your portal URL // }) // const accessToken = session.token; Cesium.ArcGisMapService.defaultAccessToken = accessToken; const cesiumAccessToken = "YOUR_CESIUM_ACCESS_TOKEN"; </script>
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Configure
Cesium.
with the Cesium access token to validate the application.Ion.default Access Token Use dark colors for code blocks <script> /* Use for API key authentication */ const accessToken = "YOUR_ACCESS_TOKEN"; // or /* Use for user authentication */ // const session = await arcgisRest.ArcGISIdentityManager.beginOAuth2({ // clientId: "YOUR_CLIENT_ID", // Your client ID from OAuth credentials // redirectUri: "YOUR_REDIRECT_URL", // The redirect URL registered in your OAuth credentials // portal: "YOUR_PORTAL_URL" // Your portal URL // }) // const accessToken = session.token; Cesium.ArcGisMapService.defaultAccessToken = accessToken; const cesiumAccessToken = "YOUR_CESIUM_ACCESS_TOKEN"; Cesium.Ion.defaultAccessToken = cesiumAccessToken; </script>
Add references to ArcGIS REST JS
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In the
<head
element, reference the> routing
andrequest
packages from ArcGIS REST JS.Use dark colors for code blocks <script src="https://cesium.com/downloads/cesiumjs/releases/1.121/Build/Cesium/Cesium.js"></script> <link href="https://cesium.com/downloads/cesiumjs/releases/1.121/Build/Cesium/Widgets/widgets.css" rel="stylesheet"> <script src="https://unpkg.com/@esri/arcgis-rest-request@4/dist/bundled/request.umd.js"></script> <script src="https://unpkg.com/@esri/arcgis-rest-routing@4/dist/bundled/routing.umd.js"></script>
Update the scene
This routing application uses a 3D object layer San Francisco. Update the scene extent to focus on San Francisco, CA.
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Update the
set
command to center on locationView [-122.38329, 37.74015, 16000]
, San Francisco.Use dark colors for code blocks viewer.camera.setView({ destination : Cesium.Cartesian3.fromDegrees(-122.38329, 37.74015, 16000), orientation : { pitch : Cesium.Math.toRadians(-70.0), } });
Create a starting location graphic
Create a Billboard
entity to indicate the location from which a service area will be calculated. You can use Billboard
entities to display custom pins and images.
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Add a new
Billboard
entity to the viewer to represent the origin location. Set theposition
of the entity tonull
.Use dark colors for code blocks viewer.camera.setView({ destination : Cesium.Cartesian3.fromDegrees(-122.38329, 37.74015, 16000), orientation : { pitch : Cesium.Math.toRadians(-70.0), } }); // Add Esri attribution // Learn more in https://esriurl.com/attribution const poweredByEsri = new Cesium.Credit("Powered by <a href='https://www.esri.com/en-us/home' target='_blank'>Esri</a>", true) viewer.creditDisplay.addStaticCredit(poweredByEsri); const origin = viewer.entities.add({ name:'start', position:null, billboard: { verticalOrigin: Cesium.VerticalOrigin.BOTTOM, heightReference: Cesium.HeightReference.CLAMP_TO_GROUND, } })
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Create a
Pin
and use it to set theBuilder image
property of the billboard.Use dark colors for code blocks const pinBuilder = new Cesium.PinBuilder(); const origin = viewer.entities.add({ name:'start', position:null, billboard: { verticalOrigin: Cesium.VerticalOrigin.BOTTOM, heightReference: Cesium.HeightReference.CLAMP_TO_GROUND, image: pinBuilder.fromColor(Cesium.Color.fromCssColorString('#ffffff'),48).toDataURL(), } })
Add a click handler
Use an event handler to set the location of the origin and when a user clicks.
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Create a
Screen
for theSpace Event Handler Viewer
that listens for left clicks. Create anon
function that runs when a click is detected.Left Click Use dark colors for code blocks image: pinBuilder.fromColor(Cesium.Color.fromCssColorString('#ffffff'),48).toDataURL(), } }) viewer.screenSpaceEventHandler.setInputAction(movement => { },Cesium.ScreenSpaceEventType.LEFT_CLICK);
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Set the position of the
origin
entity to the coordinates of the clicked location. Callviewer.data
to remove stale service area polygons.Sources.remove All() Use dark colors for code blocks viewer.screenSpaceEventHandler.setInputAction(movement => { const pickedPosition = viewer.scene.pickPosition(movement.position); origin.position = pickedPosition; viewer.dataSources.removeAll(); },Cesium.ScreenSpaceEventType.LEFT_CLICK);
Get service areas
To calculate a service area from a point, use the ArcGIS REST JS service
function to make a request to the routing service.
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Create a new
arcgis
and set your access token.Rest. Api Key Manager Use dark colors for code blocks /* Use for API key authentication */ const accessToken = "YOUR_ACCESS_TOKEN"; // or /* Use for user authentication */ // const session = await arcgisRest.ArcGISIdentityManager.beginOAuth2({ // clientId: "YOUR_CLIENT_ID", // Your client ID from OAuth credentials // redirectUri: "YOUR_REDIRECT_URL", // The redirect URL registered in your OAuth credentials // portal: "YOUR_PORTAL_URL" // Your portal URL // }) // const accessToken = session.token; Cesium.ArcGisMapService.defaultAccessToken = accessToken; const authentication = arcgisRest.ApiKeyManager.fromKey(accessToken);
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Create a function called
get
that accepts a coordinate pair. Inside, callService Area arcgis
and set theRest.service Area facilities
parameter to the set of coordinates.arcgis
creates a direct request to theRest.service Area solve
endpoint of the routing service. To learn more about theService Area solve
endpoint, go to the Routing service page in the Mapping and location services guide.Service Area Use dark colors for code blocks viewer.screenSpaceEventHandler.setInputAction(movement => { const pickedPosition = viewer.scene.pickPosition(movement.position); origin.position = pickedPosition; viewer.dataSources.removeAll(); },Cesium.ScreenSpaceEventType.LEFT_CLICK); function getServiceArea(coordinates) { arcgisRest .serviceArea({ facilities: [coordinates], authentication }) }
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Access the service response and add the returned GeoJSON to your application as a
Geo
.Json Data Source Use dark colors for code blocks function getServiceArea(coordinates) { arcgisRest .serviceArea({ facilities: [coordinates], authentication }) .then((response) => { const serviceJSON = response.saPolygons.geoJson; Cesium.GeoJsonDataSource.load(serviceJSON,{ clampToGround:true }) .then((dataSource)=>{ viewer.dataSources.add(dataSource); }); }) }
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Set the
material
of each service area polygon based on its drive time from the origin using theFrom
property.Break Use dark colors for code blocks .then((response) => { const serviceJSON = response.saPolygons.geoJson; Cesium.GeoJsonDataSource.load(serviceJSON,{ clampToGround:true }) .then((dataSource)=>{ viewer.dataSources.add(dataSource); const entities = dataSource.entities.values; for (let i=0; i<entities.length;i++) { const feature = entities[i]; feature.polygon.outline = false; if (feature.properties.FromBreak == 0) { feature.polygon.material = Cesium.Color.fromHsl(0.5833,.8,.4,.7); feature.polygon.extrudedHeight = 300; } else if (feature.properties.FromBreak == 5) { feature.polygon.material = Cesium.Color.fromHsl(0.5833,.8,.6,.7); feature.polygon.extrudedHeight = 200; } else { feature.polygon.material = Cesium.Color.fromHsl(0.5833,.8,.8,.7); feature.polygon.extrudedHeight = 100; } } }); })
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In your
on
function, convert the coordinates of the user's click fromLeft Click Cartesian
to longitude and latitude degrees. Callget
with the longitude and latitudeService Area Use dark colors for code blocks viewer.screenSpaceEventHandler.setInputAction(movement => { const pickedPosition = viewer.scene.pickPosition(movement.position); origin.position = pickedPosition; viewer.dataSources.removeAll(); const cartographic = Cesium.Cartographic.fromCartesian(pickedPosition); const originLatLng = [Cesium.Math.toDegrees(cartographic.longitude),Cesium.Math.toDegrees(cartographic.latitude)] getServiceArea(originLatLng); },Cesium.ScreenSpaceEventType.LEFT_CLICK);
Run the app
Run the app.
When the application loads, you should be able to click on a locations to create an origin point. The routing service should then calculate drive time polygons representing the areas reachable within a 5, 10, and 15 minute drive.
What's next?
Learn how to use additional ArcGIS location services in these tutorials: