DirectLineMeasurementAnalysis | References | ArcGIS Maps SDK for JavaScript

import DirectLineMeasurementAnalysis from "@arcgis/core/analysis/DirectLineMeasurementAnalysis.js";

Inheritance:: DirectLineMeasurementAnalysis→Analysis→Accessor

Since: ArcGIS Maps SDK for JavaScript 4.23

DirectLineMeasurementAnalysis computes the distance between two points and displays the measurement in a 3D SceneView.

To display a distance measurement between two points, create a new instance of DirectLineMeasurementAnalysis, add it to SceneView.analyses and set the startPoint and endPoint properties.

Use the DirectLineMeasurementAnalysisView3D to retrieve analysis results.

// create analysis
const directLineMeasurement = new DirectLineMeasurementAnalysis({
  startPoint: new Point({ }),
  endPoint: new Point({ }),
  unit: "imperial"
});

// add to the scene view
view.analyses.add(directLineMeasurement);

// retrieve measured results from analysis view once available
const analysisView = await view.whenAnalysisView(directLineMeasurement);
await reactiveUtils.whenOnce(() => analysisView.result);

const result = analysisView.result;

To place the start and end points interactively, use the DirectLineMeasurementAnalysisView3D.place() method.

const abortController = new AbortController();

try {
  await analysisView.place({ signal: abortController.signal });
} catch (error) {
  if (error.name === "AbortError") {
    console.log("Placement operation was cancelled.");
  }
}

// cancel the placement operation at some later point
abortController.abort();

How distances are computed depends on the scene's spatial reference.

In geographic coordinate systems (GCS) and in Web Mercator:

Direct distance is computed in a Euclidean manner, in an ECEF coordinate system (or equivalent on other planets);
Horizontal distance is computed geodetically, taking into consideration the curvature of the planet;
Vertical distance is computed as an elevation difference.

In projected coordinate systems (PCS), apart from Web Mercator, all three distances (direct, horizontal, and vertical) are computed in a Euclidean manner (in their respective PCS).

DirectLineMeasurementAnalysis visualizes and labels the direct, horizontal, and vertical distances When the distance between the points is greater than 100 kilometers, the measurement visualization is simplified, and in the analysis results only the horizontal and vertical distances are calculated.

measurement-line-3d

Use the Direct Line Measurement 3D component to display a user interface for the direct line measurement analysis.

Known Limitation

This analysis is only supported in a 3D SceneView.

See also

Constructors

Constructor

Parameters

Parameter	Type	Description	Required
properties	`DirectLineMeasurementAnalysisProperties`

See the properties table for a list of all the properties that may be passed into the constructor.

Properties

Any properties can be set, retrieved or listened to. See the Watch for changes topic.

Property	Type	Class
`declaredClass` readonly inherited	`string`	Accessor
`endPoint`	`Point \| null \| undefined`
`id` readonly inherited	`string`	Analysis
`origin` inherited	`AnalysisOriginWebScene \| null \| undefined`	Analysis
`startPoint`	`Point \| null \| undefined`
`type` readonly	`"direct-line-measurement"`
`uid` readonly inherited	`string`	IdentifiableMixin
`unit`	`SystemOrLengthUnit \| null \| undefined`
`valid` readonly	`boolean`

declaredClass

readonlyinherited Property

Type: string

Inherited from: Accessor

The name of the class. The declared class name is formatted as esri.folder.className.

endPoint

autocast Property

Type: Point | null | undefined

Ending point for the measurement.

If the point has a z-value then this will be treated as an absolute value, otherwise the point will be aligned to the ground.

id

readonlyinherited Property

Type: string

Inherited from: Analysis

A user settable identifier for the analysis. A unique value is automatically generated when the analysis is created if it is not set explicitly during construction.

origin

autocast inherited Property

Type: AnalysisOriginWebScene | null | undefined

Inherited from: Analysis

The origin of the analysis. The origin can be of type web-scene when the analysis was applied from the WebScene.initialViewProperties or a Slide.

startPoint

autocast Property

Type: Point | null | undefined

Starting point for the measurement.

If the point has a z-value then this will be treated as an absolute value, otherwise the point will be aligned to the ground.

type

readonly Property

Type: "direct-line-measurement"

The type of analysis. For direct line measurement analysis, this is always "direct-line-measurement".

uid

readonlyinherited Property

Type: string

Inherited from: IdentifiableMixin

Since: ArcGIS Maps SDK for JavaScript 4.33

An automatically generated unique identifier assigned to the instance. The unique id is generated each time the application is loaded.

unit

Property

Type: SystemOrLengthUnit | null | undefined

Unit system (imperial, metric) or specific unit used for computing the distance.

valid

readonly Property

Type: boolean

Since: ArcGIS Maps SDK for JavaScript 4.33

Indicates whether the analysis is ready to be computed and interacted with in the view. It requires both the startPoint and endPoint to be set.

Methods

Method	Signature	Class
`fromJSON` inherited static	`fromJSON(json: any): any`	JSONSupportMixin
`clear`	`clear(): void`
`clone` inherited	`clone(): this`	ClonableMixin
`equals` inherited	`equals(other: this): boolean`	Analysis
`toJSON` inherited	`toJSON(): any`	JSONSupportMixin

fromJSON

inheritedstatic Method

Signature: fromJSON (json: any): any

Inherited from: JSONSupportMixin

Creates a new instance of this class and initializes it with values from a JSON object generated from an ArcGIS product. The object passed into the input json parameter often comes from a response to a query operation in the REST API or a toJSON() method from another ArcGIS product. See the Using fromJSON() topic in the Guide for details and examples of when and how to use this function.

Parameters

Parameter	Type	Description	Required
json	`any`	A JSON representation of the instance in the ArcGIS format. See the ArcGIS REST API documentation for examples of the structure of various input JSON objects.

Returns: any
Returns a new instance of this class.

clear

Method

Signature: clear (): void

Since: ArcGIS Maps SDK for JavaScript 5.0

Clears the analysis by resetting the startPoint and endPoint properties.

Returns: void

clone

inherited Method

Signature: clone (): this

Inherited from: ClonableMixin

Creates a deep clone of this object. Any properties that store values by reference will be assigned copies of the referenced values on the cloned instance.

Returns: this
A deep clone of the class instance that invoked this method.

equals

inherited Method

Signature: equals (other: this): boolean

Inherited from: Analysis

Since: ArcGIS Maps SDK for JavaScript 5.0

Compares this analysis with another analysis to determine whether they are equivalent.

Parameters

Parameter	Type	Description	Required
other	`this`	The other analysis to compare against.

Returns: boolean
true if the analyses are equivalent and false otherwise.

toJSON

inherited Method

Signature: toJSON (): any

Inherited from: JSONSupportMixin

Converts an instance of this class to its ArcGIS portal JSON representation. See the Using fromJSON() guide topic for more information.

Returns: any
The ArcGIS portal JSON representation of an instance of this class.