Defines the spatial reference of a view, layer, or method parameters. This indicates the projected or geographic coordinate system used to locate geographic features in the map. Each projected and geographic coordinate system is defined by either a well-known ID (WKID) or a definition string (WKT). Note that for versions prior to ArcGIS 10, only WKID was supported. For a full list of supported spatial reference IDs and their corresponding definition strings, see Using spatial references.
// set the spatial reference of a view to WebMercator using wkid
const view = new SceneView({
container: "viewDiv",
map: map,
spatialReference: {
wkid: 3857
}
});
// set the spatial reference of a geometry
// to WGS84 using the WGS84 property
const point = new Point({
x: 10.1,
y: 47.4,
spatialReference: SpatialReference.WGS84
});
Constructors
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new SpatialReference(properties)
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Parameterproperties Objectoptional
See the properties for a list of all the properties that may be passed into the constructor.
Property Overview
Name | Type | Summary | Class |
---|---|---|---|
String | The name of the class. more details | Accessor | |
Object | An image coordinate system defines the spatial reference used to display the image in its original coordinates without distortion, map transformations or ortho-rectification. more details | SpatialReference | |
Boolean | Indicates if the spatial reference refers to a geographic coordinate system. more details | SpatialReference | |
Boolean | Indicates if the wkid of the spatial reference object is one of the following values: | SpatialReference | |
Boolean | Indicates if the wkid of the spatial reference object is | SpatialReference | |
Boolean | Indicates if the spatial reference of the map supports wrapping around the International Date Line. more details | SpatialReference | |
Number | The factor to convert one unit value in the spatial reference's unit to meters. more details | SpatialReference | |
null|String | The unit of the spatial reference. more details | SpatialReference | |
SpatialReference | A convenience spatial reference instance for Web Mercator. more details | SpatialReference | |
SpatialReference | A convenience spatial reference instance for WGS84. more details | SpatialReference | |
Number | The well-known ID of a spatial reference. more details | SpatialReference | |
String | The well-known text that defines a spatial reference. more details | SpatialReference |
Property Details
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Since: ArcGIS Maps SDK for JavaScript 4.7
-
The name of the class. The declared class name is formatted as
esri.folder.className
.
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imageCoordinateSystem ObjectSince: ArcGIS Maps SDK for JavaScript 4.13
-
An image coordinate system defines the spatial reference used to display the image in its original coordinates without distortion, map transformations or ortho-rectification. Typically, ImageryLayer is displayed in the spatialReference of the view. In some cases, converting images into map coordinates can cause your images to look skewed or distorted because of the various transformations and terrain corrections that are used. Since there is no distortion with images in the image coordinate system, it is ideal for using with oblique imagery and mensuration.
The image can be displayed in its original coordinates only in 2D MapView with a
top-up
rotation which is always oriented in the look of direction of the dataset. This works similarly to an in-car navigation system where the choices are often either north is at the top of the screen (therefore, not using a top up option) or the screen rotates so the travel direction is always displayed at the top.- See also
Example// get image coordinate system of the specified catalog item // for example Raster.OBJECTID = 1600 layer.getCatalogItemICSInfo(imageId).then(function(info) { // create a spatialReference object and set its // imageCoordinateSystem property let sr = { // autocasts to esri/geometry/SpatialReference imageCoordinateSystem: { id: imageId } }; // Calculate an extent for the mapview based on the image's extent // in its original coordinate system const width = document.getElementById("viewDiv").getBoundingClientRect().width; const height = document.getElementById("viewDiv").getBoundingClientRect().height; const newExt = info.icsExtent.clone(); const scaleFactor = 5; newExt.xmin = (newExt.xmin + newExt.xmax - width * scaleFactor) / 2; newExt.xmax = newExt.xmin + width * scaleFactor; newExt.ymin = (newExt.ymin + newExt.ymax - height * scaleFactor) / 2; newExt.ymax = newExt.ymin + height * scaleFactor; newExt.spatialReference = sr; // set the MapView's spatialReference to the image's coordinate system // and the extent to the extent calculated above view = new MapView({ container: "viewDiv", map: map, spatialReference: sr, extent: newExt }); });
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isGeographic Booleanreadonly
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Indicates if the spatial reference refers to a geographic coordinate system.
-
isWebMercator Booleanreadonly
-
Indicates if the wkid of the spatial reference object is one of the following values:
102113
,102100
,3857
.
-
isWrappable Booleanreadonly
-
Indicates if the spatial reference of the map supports wrapping around the International Date Line. Value is
true
if the spatial reference is Web Mercator or WGS84.
-
metersPerUnit NumberreadonlySince: ArcGIS Maps SDK for JavaScript 4.26
-
The factor to convert one unit value in the spatial reference's unit to meters.
Examples// Convert 1 pixel in a MapView to meters const pixelInMeter = view.resolution * view.spatialReference.metersPerUnit;
// Measure the geodesic distance between two points in the view's unit const distanceInViewUnit = geodesicUtils.geodesicDistance(pointA, pointB, "meters") / view.spatialReference.metersPerUnit;
const DPI = 96 const inchesPerMeter = 39.37; // Get the scale for an extent function getScale(extent, viewWidth) { const unitValue = extent.spatialReference.metersPerUnit; return (extent.width / viewWidth) * unitValue * inchesPerMeter * DPI; }
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Since: ArcGIS Maps SDK for JavaScript 4.26
-
The unit of the spatial reference. Returns
null
if no unit could be determined.Some values of the possible values listed here cannot be used as parameters for certain functions. For example, geodesicUtils.geodesicDistance() only accepts
meters
,feet
,us-feet
. For other values, you can use themeters
unit and use metersPerUnit convert to the spatial reference'sunit
.Possible Values:"degrees"|"meters"|"feet"|"us-feet"|"clarke-feet"|"clarke-yards"|"clarke-links"|"sears-yards"|"sears-feet"|"sears-chains"|"benoit-1895-b-chains"|"indian-yards"|"indian-1937-yards"|"gold-coast-feet"|"sears-1922-truncated-chains"|"50-kilometers"|"150-kilometers"
- See also
-
WebMercator SpatialReferencestatic
-
A convenience spatial reference instance for Web Mercator.
Example// returns true if the webMercatorUtils can // project geometries from WGS84 to Web Mercator let canProjectWGS84toWebMercator = webMercatorUtils.canProject(SpatialReference.WGS84, SpatialReference.WebMercator);
-
WGS84 SpatialReferencestatic
-
A convenience spatial reference instance for WGS84.
Example// returns true if the webMercatorUtils can // project geometries from WGS84 to Web Mercator let canProjectWGS84toWebMercator = webMercatorUtils.canProject(SpatialReference.WGS84, SpatialReference.WebMercator);
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wkid Number
-
The well-known ID of a spatial reference. See Using spatial references for a list of supported spatial references.
-
wkt String
-
The well-known text that defines a spatial reference.
Method Overview
Name | Return Type | Summary | Class |
---|---|---|---|
Adds one or more handles which are to be tied to the lifecycle of the object. more details | Accessor | ||
SpatialReference | Returns a deep clone of the spatial reference object. more details | SpatialReference | |
Boolean | Checks if the specified spatial reference object has the same wkid or wkt as this spatial reference object. more details | SpatialReference | |
* | Creates a new instance of this class and initializes it with values from a JSON object generated from an ArcGIS product. more details | SpatialReference | |
Boolean | Returns true if a named group of handles exist. more details | Accessor | |
Removes a group of handles owned by the object. more details | Accessor | ||
Object | Converts an instance of this class to its ArcGIS portal JSON representation. more details | SpatialReference |
Method Details
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addHandles(handleOrHandles, groupKey)inheritedSince: ArcGIS Maps SDK for JavaScript 4.25
-
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();
ParametershandleOrHandles WatchHandle|WatchHandle[]Handles marked for removal once the object is destroyed.
groupKey *optionalKey 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.
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clone(){SpatialReference}
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Returns a deep clone of the spatial reference object.
ReturnsType Description SpatialReference Returns a deep clone of the spatial reference object.
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equals(spatialReference){Boolean}
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Checks if the specified spatial reference object has the same wkid or wkt as this spatial reference object.
ParameterspatialReference SpatialReferenceThe spatial reference to compare to.
ReturnsType Description Boolean Returns true
if the input spatial reference object has the same wkid or wkt as this spatial reference object.Examplerequire(["esri/geometry/SpatialReference"], function(SpatialReference) { const sr1 = new SpatialReference({ wkid: 4326 }); const sr2 = new SpatialReference({ wkid: 4326 }); console.log(sr1.equals(sr2)); // true });
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fromJSON(json){*}static
-
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.Parameterjson ObjectA 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.
ReturnsType Description * Returns a new instance of this class.
-
Since: ArcGIS Maps SDK for JavaScript 4.25
-
Returns true if a named group of handles exist.
ParametergroupKey *optionalA group key.
ReturnsType 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(groupKey)inheritedSince: ArcGIS Maps SDK for JavaScript 4.25
-
Removes a group of handles owned by the object.
ParametergroupKey *optionalA group key or an array or collection of group keys to remove.
Exampleobj.removeHandles(); // removes handles from default group obj.removeHandles("handle-group"); obj.removeHandles("other-handle-group");
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toJSON(){Object}
-
Converts an instance of this class to its ArcGIS portal JSON representation. See the Using fromJSON() guide topic for more information.
ReturnsType Description Object The ArcGIS portal JSON representation of an instance of this class.