heatmap | References | ArcGIS Maps SDK for JavaScript

import { getThemes, getSchemes, getSchemeByName, getSchemesByTag, cloneScheme } from "@arcgis/core/smartMapping/symbology/heatmap.js";

Since: ArcGIS Maps SDK for JavaScript 4.11

Object containing helper methods for generating optimal colors for heatmap visualizations. The getSchemes() method is used to get the heatmap color schemes best suited to the given basemap.

Functions

Name	Return Type	Object
`getThemes`	`Theme[]`
`getSchemes`	`HeatmapSchemes \| null \| undefined`
`GetSchemesParameters`
`getSchemeByName`	`HeatmapScheme \| null \| undefined`
`getSchemesByTag`	`HeatmapScheme[]`
`cloneScheme`	`HeatmapScheme \| null \| undefined`
`GetSchemesByNameParameters`
`GetSchemesByTagParameters`

getThemes

Function

Returns metadata for the available themes. If a basemap is provided, returns themes that work best with the given basemap.

Signature: getThemes (basemap?: Basemap | string): Theme[]

Parameters

Parameter	Type	Description	Required
basemap	`Basemap \| string`	The Esri basemap string or object that will be used with the returned theme(s).

Returns: Theme[]
Returns an object containing information about the available themes for the given basemap.

getSchemes

Function

Returns a primary scheme and secondary schemes defining properties for heatmap visualizations in a point Layer. The basemap parameter determines the color schemes of the heatmap.

Signature: getSchemes (params: GetSchemesParameters): HeatmapSchemes | null | undefined

Parameters

Parameter	Type	Description	Required
params	`GetSchemesParameters`	The function parameters.

Returns: HeatmapSchemes | null | undefined
Returns an object containing the optimal heatmap scheme to use for the given basemap and secondary schemes that may also be used.

Example

// gets the primary scheme for the basemap
let schemes = heatmapSchemes.getSchemes({
  basemap: map.basemap
});

// the best default scheme for the layer, basemap, and theme
let primaryScheme = schemes.primaryScheme;

getSchemeByName

Function

Since: ArcGIS Maps SDK for JavaScript 4.12

Returns a heatmap scheme with the provided name.

Signature: getSchemeByName (params: GetSchemesByNameParameters): HeatmapScheme | null | undefined

Parameters

Parameter	Type	Description	Required
params	`GetSchemesByNameParameters`	The function parameters.

Returns: HeatmapScheme | null | undefined
Returns the heatmap scheme with the given name.

Example

// Returns the Heatmap 4 scheme
let heatmapScheme = heatmapSchemes.getSchemeByName({
  basemap: map.basemap,
  name: "Heatmap 4"
});

getSchemesByTag

Function

Since: ArcGIS Maps SDK for JavaScript 4.12

Returns an array of heatmap schemes with the provided tags. These schemes define color stop properties for any layer that can be rendered with a HeatmapRenderer.

Signature: getSchemesByTag (params: GetSchemesByTagParameters): HeatmapScheme[]

Parameters

Parameter	Type	Description	Required
params	`GetSchemesByTagParameters`	The function parameters.

Returns: HeatmapScheme[]
Returns an array of heatmap schemes either including or excluding the provided tags.

Example

// Returns all the heatmap schemes that look good in grayscale
let grayscaleSchemes = heatmapSchemes.getSchemesByTag({
  basemap: map.basemap,
  includedTags: [ "heatmap", "grayscale" ]
});

cloneScheme

Function

Clones a heatmap scheme object.

Signature: cloneScheme (scheme: HeatmapScheme | null | undefined): HeatmapScheme | null | undefined

Parameters

Parameter	Type	Description	Required
scheme	`HeatmapScheme \| null \| undefined`	The heatmap scheme object to clone.

Returns: HeatmapScheme | null | undefined
A clone of the given heatmap scheme object.

Example

// clones the primary scheme returned from the getSchemes() method
let heatmapScheme = primaryScheme.clone();

Type definitions

GetSchemesParameters

Type definition

basemap

Property

Type: Basemap | string | null | undefined

The Esri basemap to pair with the visualization. This value indicates the best colors for visualizing features against the given basemap. If you have a non-Esri basemap (e.g. a VectorTileLayer basemap with a custom style) or no basemap at all, then use the basemapTheme parameter instead of this parameter.

basemapTheme

Property

Type: BasemapTheme | null | undefined

If you have a non-Esri basemap (e.g. a VectorTileLayer basemap with a custom style) or no basemap at all, use this parameter to indicate whether the background of the visualization is light or dark.