Viewshed | API Reference | ArcGIS Maps SDK for JavaScript 4.30

Viewshed defines the geometry for a viewshed analysis. The viewshed is determined by a position, distance, orientation (defined by heading and tilt), and field of view angles.

 const viewshed = new Viewshed({
   observer: {
     spatialReference: {
       latestWkid: 3857,
       wkid: 102100
     },
     x: -9754426,
     y: 5143111,
     z: 330
   },
   farDistance: 900,
   heading: 64,
   tilt: 84,
   horizontalFieldOfView: 85,
   verticalFieldOfView: 52
 });
 const viewshedAnalysis = new ViewshedAnalysis({
   viewsheds: [viewshed],
 });

 view.analyses.add(viewshedAnalysis);

To create a view dome, set horizontalFieldOfView to 360, and verticalFieldOfView to 180.

See also

Constructors

Viewshed Constructor new Viewshed(properties)

Parameter

properties Object

optional

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

Property Overview

Any properties can be set, retrieved or listened to. See the Working with Properties topic.

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Type	Summary	Class
String	The name of the class.	Accessor
Number	The maximum distance from the observer in which to perform the viewshed analysis (in meters).	Viewshed
Number	The compass heading of the observer's view direction (in degrees).	Viewshed
Number	The horizontal field of view (FOV) angle defines how wide scope is analysed (in degrees).	Viewshed
Point	A Point specifying the position the viewshed is calculated from.	Viewshed
Number	The tilt of the observer's view direction (in degrees).	Viewshed
Number	The vertical field of view (FOV) angle defines how tall scope is analysed (in degrees).	Viewshed

Property Details

declaredClass Inherited Property declaredClass Stringreadonly Inherited from Accessor

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

farDistance Property farDistance Number

The maximum distance from the observer in which to perform the viewshed analysis (in meters).

heading Property heading Number

The compass heading of the observer's view direction (in degrees). A heading of zero points the viewshed to north and it increases as the viewshed rotates clockwise.

Default Value:0

horizontalFieldOfView Property horizontalFieldOfView Number

The horizontal field of view (FOV) angle defines how wide scope is analysed (in degrees). A value of 360 means the observer's horizontal FOV captures their entire surroundings. Values closer to 0 narrow the horizontal FOV in the direction of the heading.

Default Value:45

observer Property observer Pointautocast

A Point specifying the position the viewshed is calculated from.

tilt Property tilt Number

The tilt of the observer's view direction (in degrees). A tilt of zero points the viewshed looking straight down and 90 degrees points it looking parallel to the surface.

Default Value:90

verticalFieldOfView Property verticalFieldOfView Number

The vertical field of view (FOV) angle defines how tall scope is analysed (in degrees). This value can vary from 0 to 180. Values closer to 0 narrow the vertical FOV in the direction of the tilt.

Default Value:45

Method Overview

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Return Type	Summary	Class
	Adds one or more handles which are to be tied to the lifecycle of the object.	Accessor
this	Creates a deep clone of this object.	Viewshed
Boolean	Returns true if a named group of handles exist.	Accessor
	Removes a group of handles owned by the object.	Accessor

Method Details

addHandles Inherited Method addHandles(handleOrHandles, groupKey) Inherited from Accessor

Adds one or more handles which are to be tied to the lifecycle of the object. The handles will be removed when the object is destroyed.

// Manually manage handles
const handle = reactiveUtils.when(
  () => !view.updating,
  () => {
    wkidSelect.disabled = false;
  },
  { once: true }
);

this.addHandles(handle);

// Destroy the object
this.destroy();

Parameters

handleOrHandles WatchHandle|WatchHandle []

Handles marked for removal once the object is destroyed.

groupKey *

optional

Key identifying the group to which the handles should be added. All the handles in the group can later be removed with Accessor.removeHandles(). If no key is provided the handles are added to a default group.

clone Method clone(){this}

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

Type	Description
this	A deep clone of the class instance that invoked this method.

hasHandles Inherited Method hasHandles(groupKey){Boolean} Inherited from Accessor

Returns true if a named group of handles exist.

Parameter

groupKey *

optional

A group key.

Returns

Type	Description
Boolean	Returns `true` if a named group of handles exist.

Example

// Remove a named group of handles if they exist.
if (obj.hasHandles("watch-view-updates")) {
  obj.removeHandles("watch-view-updates");
}

removeHandles Inherited Method removeHandles(groupKey) Inherited from Accessor

Removes a group of handles owned by the object.

Parameter

groupKey *

optional

A group key or an array or collection of group keys to remove.

Example

obj.removeHandles(); // removes handles from default group

obj.removeHandles("handle-group");
obj.removeHandles("other-handle-group");