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esri/dijit/util
esri/layer/pixelFilters
esri/process
esri/workers
Class: RasterLayer

require(["esri/layers/RasterLayer"], function(RasterLayer) { /* code goes here */ });

Description

(Added at v3.13)
The RasterLayer is used to display image services. It retrieves data from image services and applies client side pixel filtering (e.g. mask, stretch). This layer is particularly useful when you need to interactively change pixel manipulation criteria and get an immediate response.

Samples

Search for samples that use this class.

Class hierarchy

esri/layers/Layer
|_esri/layers/RasterLayer

Constructors

NameSummary
new RasterLayer(url, options?)Creates a new RasterLayer object.

Properties

NameTypeSummary
attributionDataUrlStringThe URL, when available, where the layer's attribution data is stored.
classNameStringclass attribute of the layer's node.
credentialCredentialProvides credential information for the layer such as userid and token if the layer represents a resource that is secured with token-based authentication.
hasAttributionDataBooleanWhen true, the layer has attribution data.
idStringID assigned to the layer.
loadErrorErrorSet if the layer failed to load.
loadedBooleanWhen the layer is loaded, the value becomes "true", and layer properties can be accessed.
maxScaleNumberMaximum visible scale for the layer.
minScaleNumberMinimum visible scale for the layer.
opacityNumberOpacity or transparency of layer.
pixelFilterFunctionA function that takes a pixelData object as input and processes it.
refreshIntervalNumberRefresh interval of the layer in minutes.
showAttributionBooleanWhen true, the layer's attribution is displayed on the map.
suspendedBooleanWhen true, the layer is suspended.
urlStringURL to the ArcGIS Server REST resource that represents a map service.
visibleBooleanVisibility of the layer.
visibleAtMapScaleBooleanWhen true, the layer is visible at the current map scale.

Methods

NameReturn typeSummary
attr(name, value)LayerAdds a new attribute or changes the value of an existing attribute on the layer's node.
getAttributionData()DeferredAsynchrously returns custom data for the layer when available.
getContext()ObjectReturns the context of the Canvas.
getMap()MapReturns reference to the map control the layer is added to.
getNode()HTMLElementReturns the layer's DOM node.
hide()NoneSets the visibility of the layer to "false".
isVisibleAtScale(scale)BooleanReturns true if the layer is visible at the given scale.
resume()NoneResumes layer drawing.
setImageFormat(imageFormat, doNotRefresh?)NoneSets the image format.
setMaxScale(scale)NoneSet the maximum scale for the layer.
setMinScale(scale)NoneSet the minimum scale for the layer.
setOpacity(opacity)NoneSets the opacity of the layer.
setPixelFilter(pixelFilter)NoneSets a pixelFilter on the layer.
setRefreshInterval(interval)LayerChanges the layer's refresh interval to the given value (in minutes).
setScaleRange(minScale, maxScale)NoneSet the scale range for the layer.
setUseMapTime(use, doNotRefresh?)NoneDetermines if the layer will update its content based on the map's current time extent.
setVisibility(isVisible)NoneSets the visibility of the layer.
show()NoneSets the visibility of the layer to "true".
suspend()NoneSuspends layer drawing.

Events

[ On Style Events | Connect Style Event ]
All On Style event listeners receive a single event object. Additionally, the event object also contains a 'target' property whose value is the object which fired the event.

Events

NameEvent ObjectSummary
error
{
  error: <Error>
}
Fires when there is a problem retrieving a layer.
load
{
  layer: <Layer>
}
Fires after layer properties for the layer are successfully populated.
opacity-change
{
  opacity: <Number>
}
Fires when the layer opacity has been changed, and returns an object with the opacity value.
refresh-interval-changeThis event is fired when the layer's refreshInterval is modified.
resumeFires when a layer resumes drawing.
scale-range-changeFires when a layer's minScale and/or maxScale is changed.
scale-visibility-changeFires when a layer's scale visibility changes.
suspendFires when a layer suspends drawing.
updateFires any time a layer has finished loading or updating itself.
update-end
{
  error: <Error>
}
Fires when a layer has finished updating its content.
update-startFires when a layer begins to update its content.
visibility-change
{
  visible: <Boolean>
}
Fires when the layer visibility has been changed, and returns an object with a Boolean visible property containing the new visibility value of the layer.
Constructor Details

new RasterLayer(url, options?)

Creates a new RasterLayer object.
Parameters:
<String> url Required URL to the ArcGIS Server REST resource that represents a raster layer service. For more information on constructing a URL, see The Services Directory and the REST API.
<Object> options Optional Optional parameters. See options list below.
options properties:
<Boolean> drawMode Optional Sets the layer's draw mode. Set to false if using drawType: "webgl" since pixels are rendered by webgl shaders instead of this layer.
<String> drawType Optional Sets the context of the Canvas. Known values: "2d" | "webgl" | "experimental-webgl" | "webgl2" | "experimental-webgl2"
<ImageServiceParameters> imageServiceParameters Optional Additional parameters defined in an ImageServiceParameters object.
<Object> pixelFilter Optional Applies a function for visualization or post-processing purposes.
Sample:
var isRasterLayer = new RasterLayer(isUrl, {
  opacity: 1,
  pixelFilter: pixelFilter.hillshade,  //Class that draws hillshades  using a frequent-shader
  drawMode: false,
  drawType: "experimental-webgl"
});
Property Details

<String> attributionDataUrl

The URL, when available, where the layer's attribution data is stored. (Added at v3.1)

<String> className

class attribute of the layer's node. (Added at v3.7)

<Credential> credential

Provides credential information for the layer such as userid and token if the layer represents a resource that is secured with token-based authentication. This value is available after the layer has been loaded i.e. layer.loaded is true. (Added at v2.5)

<Boolean> hasAttributionData

When true, the layer has attribution data. Use the getAttributionData method to retrieve this data as JSON. (Added at v3.1)
Known values: true | false
Default value: false

<String> id

ID assigned to the layer. If not assigned, esri.Map assigns value. By default, the ID of the layer is "layer" followed by a number. The ID can be user defined only in the layer constructor.
Sample:
  • Setting the layer ID in the layer constructor.
    require([
      "esri/layers/ArcGISDynamicMapServiceLayer", ... 
    ], function(ArcGISDynamicMapServiceLayer, ... ) {
      var population = new ArcGISDynamicMapServiceLayer("http://myserver/arcgis/rest/population/MapServer/Layers", {id:"population"});
      ...
    });
    
  • Setting the layer ID after a layer is initialized.
    population.id = "population";
    
  • Retrieving the layer ID.
    function getMapLayers() {
      for (var j=0, jl=map.layerIds.length; j<jl; j++) {
        var currentLayer = map.getLayer(map.layerIds[j]);
        alert("id: " + currentLayer.id);
      }
    }
    

<Error> loadError

Set if the layer failed to load. (Added at v3.9)

<Boolean> loaded

When the layer is loaded, the value becomes "true", and layer properties can be accessed. The onLoad event is also fired.
Known values: true | false

<Number> maxScale

Maximum visible scale for the layer. If the map is zoomed in beyond this scale, the layer will not be visible. A value of 0 means the layer does not have a maximum scale. (Added at v3.1)
Default value: 0

<Number> minScale

Minimum visible scale for the layer. If the map is zoomed out beyond this scale, the layer will not be visible. A value of 0 means the layer does not have a visible scale. (Added at v3.1)
Default value: 0

<Number> opacity

Opacity or transparency of layer. Values range from 0.0 to 1.0, where 0.0 is 100% transparent and 1.0 has no transparency.
Known values: 0.0 - 1.0
Default value: 1.0

<Function> pixelFilter

A function that takes a pixelData object as input and processes it. The pixelData object contains a pixelBlock property that gives you access to all of the pixels in the raster.

Inside the pixelFilter, you may loop through pixels through the pixelBlock property of the pixelData object and process them. See the RasterLayer sample for an example of how to apply a pixelFilter to a RasterLayer.

(Added at v3.15)

<Number> refreshInterval

Refresh interval of the layer in minutes. Non-zero value indicates automatic layer refresh at the specified interval. Value of 0 indicates auto refresh is not enabled. (Added at v3.7)

<Boolean> showAttribution

When true, the layer's attribution is displayed on the map. (Added at v3.1)
Known values: true | false
Default value: true

<Boolean> suspended

When true, the layer is suspended. A layer is considered to be suspended when one of the following is true:
  • The layer is hidden.
  • The layer is not visible at the current map scale.
  • The layer is explicitly suspended by calling the Layer.suspend method.
(Added at v3.1)
Known values: true | false

<String> url

URL to the ArcGIS Server REST resource that represents a map service. To obtain the URL, use Services Directory. An example URL for the Street Map service on ArcGIS Online is:
http://server.arcgisonline.com/ArcGIS/rest/services/ESRI_StreetMap_World_2D/MapServer. (Added at v1.2)

<Boolean> visible

Visibility of the layer.
Known values: true | false
Default value: true

<Boolean> visibleAtMapScale

When true, the layer is visible at the current map scale. (Added at v3.1)
Known values: true | false
Method Details

attr(name, value)

Adds a new attribute or changes the value of an existing attribute on the layer's node. Removes the attribute if the value is null or undefined. (Added at v3.7)
Return type: Layer
Parameters:
<String> name Required The name of the attribute.
<String> value Required The value of the attribute. Set this value as null to remove the attribute.

getAttributionData()

Asynchrously returns custom data for the layer when available. (Added at v3.1)
Return type: Deferred

getContext()

Returns the context of the Canvas. Known values are CanvasRenderingContext2D | WebGLRenderingContext | WebGL2RenderingContext
Return type: Object

getMap()

Returns reference to the map control the layer is added to. Returns null or undefined if it is not added to a map. (Added at v3.7)
Return type: Map

getNode()

Returns the layer's DOM node. (Added at v3.7)
Return type: HTMLElement

hide()

Sets the visibility of the layer to "false". The layer is not removed, but it is hidden from view.

isVisibleAtScale(scale)

Returns true if the layer is visible at the given scale. (Added at v3.1)
Return type: Boolean
Parameters:
<Number> scale Required The scale at which to check if the layer is visible.

resume()

Resumes layer drawing. (Added at v3.1)

setImageFormat(imageFormat, doNotRefresh?)

Sets the image format. In general, use lerc format when needing to use a pixel filter on the raster layer; otherwise use jpeg. Pixel filter may be performed on a jpeg image if the image service is 8 bit and uses lossy compressed data. (Added at v3.14)
Parameters:
<String> imageFormat Required The image format to set.

Possible Values: lerc | jpeg | jpgpng | png | png8 | png24 | png32 | bip | bsq
<Boolean> doNotRefresh Optional Use true to avoid refreshing the layer; false to refresh it.

setMaxScale(scale)

Set the maximum scale for the layer. (Added at v3.1)
Parameters:
<Number> scale Required The maximum scale at which the layer is visible.

setMinScale(scale)

Set the minimum scale for the layer. (Added at v3.1)
Parameters:
<Number> scale Required The minimum scale at which the layer is visible.

setOpacity(opacity)

Sets the opacity of the layer. Values range from 0.0 to 1.0, where 0.0 is 100% transparent and 1.0 has no transparency.
Parameters:
<Number> opacity Required Value from 0 to 1, where 0 is 100% transparent and 1 has no transparency. The default value is 1.
Sample:

layer.setOpacity(0.5);

setPixelFilter(pixelFilter)

Sets a pixelFilter on the layer. A pixel filter is a function that takes a pixelData object as input and processes it. The pixelData object contains a pixelBlock property that gives you access to all of the pixels in the raster.

Inside the pixelFilter, you may loop through pixels through the pixelBlock property of the pixelData object and process them. See the RasterLayer sample for an example of how to apply a pixelFilter to a RasterLayer.

(Added at v3.15)
Parameters:
<Function> pixelFilter Required The function defining the PixelFilter to set on the layer. It sets the value of the pixelFilter property.

setRefreshInterval(interval)

Changes the layer's refresh interval to the given value (in minutes). Non-zero value sets up automatic layer refresh at the specified interval. Value of 0 stops auto refresh. (Added at v3.7)
Return type: Layer
Parameters:
<Number> interval Required Refresh interval of the layer in minutes. Non-zero value indicates automatic layer refresh at the specified interval. Value of 0 indicates auto refresh is not enabled.

setScaleRange(minScale, maxScale)

Set the scale range for the layer. If minScale and maxScale are set to 0 then the layer will be visible at all scales. (Added at v3.1)
Parameters:
<Number> minScale Required The minimum scale at which the layer is visible.
<Number> maxScale Required The maximum scale at which the layer is visible.

setUseMapTime(use, doNotRefresh?)

Determines if the layer will update its content based on the map's current time extent. (Added at v3.14)
Parameters:
<Boolean> use Required Use true to update the layer's content based on the map's current time extent.
<Boolean> doNotRefresh Optional Use true to avoid refreshing the layer; false to refresh the layer.

setVisibility(isVisible)

Sets the visibility of the layer. When true, the layer is visible.
Parameters:
<Boolean> isVisible Required Set the visibility of the layer.

show()

Sets the visibility of the layer to "true".

suspend()

Suspends layer drawing. (Added at v3.1)
Event Details
[ On Style Events | Connect Style Event ]

error

Fires when there is a problem retrieving a layer. Should be used in favor of onError. (Added at v3.5)
Event Object Properties:
<Error> error ArcGIS Server error message returned in a JavaScript error object.

load

Fires after layer properties for the layer are successfully populated. This event must be successful before the layer can be added to the map. Should be used in favor of onLoad. (Added at v3.5)
Event Object Properties:
<Layer> layer The loaded layer.

opacity-change

Fires when the layer opacity has been changed, and returns an object with the opacity value. Should be used in favor of onOpacityChange. (Added at v3.5)
Event Object Properties:
<Number> opacity Fires when the layer opacity (transparency) changes. A number property named opacity that indicates the new opacity. Values range from 0.0 to 1.0, where 0.0 is 100% transparent and 1.0 has no transparency.

refresh-interval-change

This event is fired when the layer's refreshInterval is modified. (Added at v3.7)

resume

Fires when a layer resumes drawing. Should be used in favor of onResume. (Added at v3.5)

scale-range-change

Fires when a layer's minScale and/or maxScale is changed. Should be used in favor of onScaleRangeChange. (Added at v3.5)

scale-visibility-change

Fires when a layer's scale visibility changes. The scale visibility changes when a layer is initially visible and becomes invisible because the map scale does not intersect the layer's scale range or vice versa. Should be used in favor of onScaleVisibilityChange. (Added at v3.5)

suspend

Fires when a layer suspends drawing. Should be used in favor of onSuspend. (Added at v3.5)

update

Fires any time a layer has finished loading or updating itself. For an ArcGISTiledMapServiceLayer, the event fires when all required tiles have been retrieved and displayed. For an ArcGISDynamicMapServiceLayer or ArcGISImageServiceLayer, the event fires when the map image has been retrieved and displayed. For a GraphicsLayer, the event fires when all graphics have been redrawn after a pan or zoom. Deprecated at v2.0. Use update-start and update-end instead. (Added at v3.6)

update-end

Fires when a layer has finished updating its content. It is the responsibility of the subclass to determine when this event is fired. Should be used in favor of onUpdateEnd. (Added at v3.5)
Event Object Properties:
<Error> error Optional argument. The error object is available when an error occurs during the update.

update-start

Fires when a layer begins to update its content. It is the responsibility of the subclass to determine when this event is fired. Should be used in favor of onUpdateStart. (Added at v3.5)

visibility-change

Fires when the layer visibility has been changed, and returns an object with a Boolean visible property containing the new visibility value of the layer. Should be used in favor of onVisibilityChange. (Added at v3.5)
Event Object Properties:
<Boolean> visible Fires when the layer visibility changes. A boolean property named visible indicates whether or not the layer is visible after visibility changed.