# ArcGisMapServerImageryProvider

#### new Cesium.ArcGisMapServerImageryProvider(options)
Scene/ArcGisMapServerImageryProvider.js 94

Provides tiled imagery hosted by an ArcGIS MapServer. By default, the server's pre-cached tiles are used, if available.

Name | Type | Description
--- | --- | ---
`options` | ArcGisMapServerImageryProvider.ConstructorOptions | Object describing initialization options

##### Example:

    var esri = new Cesium.ArcGisMapServerImageryProvider({
        url : 'https://services.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer'
    });

##### See:

- BingMapsImageryProvider
- GoogleEarthEnterpriseMapsProvider
- OpenStreetMapImageryProvider
- SingleTileImageryProvider
- TileMapServiceImageryProvider
- WebMapServiceImageryProvider
- WebMapTileServiceImageryProvider
- UrlTemplateImageryProvider
- ArcGIS Server REST API
- Cross-Origin Resource Sharing

### Members

#### readonly credit : Credit
Scene/ArcGisMapServerImageryProvider.js 616

Gets the credit to display when this imagery provider is active. Typically this is used to credit the source of the imagery. This function should not be called before `ArcGisMapServerImageryProvider#ready` returns true.

#### defaultAlpha : Number|undefined
Scene/ArcGisMapServerImageryProvider.js 109

The default alpha blending value of this provider, with 0.0 representing fully transparent and 1.0 representing fully opaque.

Default Value: `undefined`

#### defaultBrightness : Number|undefined
Scene/ArcGisMapServerImageryProvider.js 136

The default brightness of this provider. 1.0 uses the unmodified imagery color. Less than 1.0 makes the imagery darker while greater than 1.0 makes it brighter.

Default Value: `undefined`

#### defaultContrast : Number|undefined
Scene/ArcGisMapServerImageryProvider.js 145

The default contrast of this provider. 1.0 uses the unmodified imagery color. Less than 1.0 reduces the contrast while greater than 1.0 increases it.

Default Value: `undefined`

#### defaultDayAlpha : Number|undefined
Scene/ArcGisMapServerImageryProvider.js 127

The default alpha blending value on the day side of the globe of this provider, with 0.0 representing fully transparent and 1.0 representing fully opaque.

Default Value: `undefined`

#### defaultGamma : Number|undefined
Scene/ArcGisMapServerImageryProvider.js 170

The default gamma correction to apply to this provider. 1.0 uses the unmodified imagery color.

Default Value: `undefined`

#### defaultHue : Number|undefined
Scene/ArcGisMapServerImageryProvider.js 153

The default hue of this provider in radians. 0.0 uses the unmodified imagery color.

Default Value: `undefined`

#### defaultMagnificationFilter : TextureMagnificationFilter
Scene/ArcGisMapServerImageryProvider.js 186

The default texture magnification filter to apply to this provider.

Default Value: `undefined`

#### defaultMinificationFilter : TextureMinificationFilter
Scene/ArcGisMapServerImageryProvider.js 178

The default texture minification filter to apply to this provider.

Default Value: `undefined`

#### defaultNightAlpha : Number|undefined
Scene/ArcGisMapServerImageryProvider.js 118

The default alpha blending value on the night side of the globe of this provider, with 0.0 representing fully transparent and 1.0 representing fully opaque.

Default Value: `undefined`

#### defaultSaturation : Number|undefined
Scene/ArcGisMapServerImageryProvider.js 162

The default saturation of this provider. 1.0 uses the unmodified imagery color. Less than 1.0 reduces the saturation while greater than 1.0 increases it.

Default Value: `undefined`

#### enablePickFeatures : Boolean
Scene/ArcGisMapServerImageryProvider.js 242

Gets or sets a value indicating whether feature picking is enabled. If true, `ArcGisMapServerImageryProvider#pickFeatures` will invoke the "identify" operation on the ArcGIS server and return the features included in the response. If false, `ArcGisMapServerImageryProvider#pickFeatures` will immediately return undefined (indicating no pickable features) without communicating with the server.

Default Value: `true`

#### readonly errorEvent : Event
Scene/ArcGisMapServerImageryProvider.js 579

Gets an event that is raised when the imagery provider encounters an asynchronous error. By subscribing to the event, you will be notified of the error and can potentially recover from it. Event listeners are passed an instance of `TileProviderError`.

#### readonly hasAlphaChannel : Boolean
Scene/ArcGisMapServerImageryProvider.js 651

Gets a value indicating whether or not the images provided by this imagery provider include an alpha channel. If this property is false, an alpha channel, if present, will be ignored. If this property is true, any images without an alpha channel will be treated as if their alpha is 1.0 everywhere. When this property is false, memory usage and texture upload time are reduced.

Default Value: `true`

#### layers : String
Scene/ArcGisMapServerImageryProvider.js 663

Gets the comma-separated list of layer IDs to show.

#### readonly maximumLevel : Number|undefined
Scene/ArcGisMapServerImageryProvider.js 481

Gets the maximum level-of-detail that can be requested. This function should not be called before `ArcGisMapServerImageryProvider#ready` returns true.

#### readonly minimumLevel : Number
Scene/ArcGisMapServerImageryProvider.js 500

Gets the minimum level-of-detail that can be requested. This function should not be called before `ArcGisMapServerImageryProvider#ready` returns true.

#### readonly proxy : Proxy
Scene/ArcGisMapServerImageryProvider.js 430

Gets the proxy used by this provider.

#### readonly ready : Boolean
Scene/ArcGisMapServerImageryProvider.js 591

Gets a value indicating whether or not the provider is ready for use.

#### readonly readyPromise : Promise.<Boolean>
Scene/ArcGisMapServerImageryProvider.js 603

Gets a promise that resolves to true when the provider is ready for use.

#### readonly rectangle : Rectangle
Scene/ArcGisMapServerImageryProvider.js 538

Gets the rectangle, in radians, of the imagery provided by this instance. This function should not be called before `ArcGisMapServerImageryProvider#ready` returns true.

#### readonly tileDiscardPolicy : TileDiscardPolicy
Scene/ArcGisMapServerImageryProvider.js 559

Gets the tile discard policy. If not undefined, the discard policy is responsible for filtering out "missing" tiles via its shouldDiscardImage function. If this function returns undefined, no tiles are filtered. This function should not be called before `ArcGisMapServerImageryProvider#ready` returns true.

#### readonly tileHeight : Number
Scene/ArcGisMapServerImageryProvider.js 462

Gets the height of each tile, in pixels. This function should not be called before `ArcGisMapServerImageryProvider#ready` returns true.

#### readonly tileWidth : Number
Scene/ArcGisMapServerImageryProvider.js 443

Gets the width of each tile, in pixels. This function should not be called before `ArcGisMapServerImageryProvider#ready` returns true.

#### readonly tilingScheme : TilingScheme
Scene/ArcGisMapServerImageryProvider.js 519

Gets the tiling scheme used by this provider. This function should not be called before `ArcGisMapServerImageryProvider#ready` returns true.

#### readonly token : String
Scene/ArcGisMapServerImageryProvider.js 418

Gets the ArcGIS token used to authenticate with the ArcGis MapServer service.

#### readonly url : String
Scene/ArcGisMapServerImageryProvider.js 406

Gets the URL of the ArcGIS MapServer.

#### readonly usingPrecachedTiles : Boolean
Scene/ArcGisMapServerImageryProvider.js 633

Gets a value indicating whether this imagery provider is using pre-cached tiles from the ArcGIS MapServer. If the imagery provider is not yet ready (`ArcGisMapServerImageryProvider#ready`), this function will return the value of `options.usePreCachedTilesIfAvailable`, even if the MapServer does not have pre-cached tiles.

Default Value: `true`

### Methods

#### getTileCredits(x, y, level) → Array.<Credit>
Scene/ArcGisMapServerImageryProvider.js 680

Gets the credits to be displayed when a given tile is displayed.

Name | Type | Description
--- | --- | ---
`x` | Number | The tile X coordinate.
`y` | Number | The tile Y coordinate.
`level` | Number | The tile level;

##### Returns:

The credits to be displayed when the tile is displayed.

##### Throws:

- DeveloperError : `getTileCredits` must not be called before the imagery provider is ready.

#### pickFeatures(x, y, level, longitude, latitude) → Promise.<Array.<ImageryLayerFeatureInfo>>|undefined
Scene/ArcGisMapServerImageryProvider.js 725

/** Asynchronously determines what features, if any, are located at a given longitude and latitude within a tile. This function should not be called before `ImageryProvider#ready` returns true.

Name | Type | Description
--- | --- | ---
`x` | Number | The tile X coordinate.
`y` | Number | The tile Y coordinate.
`level` | Number | The tile level.
`longitude` | Number | The longitude at which to pick features.
`latitude` | Number | The latitude at which to pick features.

##### Returns:

A promise for the picked features that will resolve when the asynchronous picking completes. The resolved value is an array of `ImageryLayerFeatureInfo` instances. The array may be empty if no features are found at the given location.

##### Throws:

- DeveloperError : `pickFeatures` must not be called before the imagery provider is ready.

#### requestImage(x, y, level, request) → Promise.<(HTMLImageElement|HTMLCanvasElement)>|undefined
Scene/ArcGisMapServerImageryProvider.js 699

Requests the image for a given tile. This function should not be called before `ArcGisMapServerImageryProvider#ready` returns true.

Name | Type | Description
--- | --- | ---
`x` | Number | The tile X coordinate.
`y` | Number | The tile Y coordinate.
`level` | Number | The tile level.
`request` | Request | optional The request object. Intended for internal use only.

##### Returns:

A promise for the image that will resolve when the image is available, or undefined if there are too many active requests to the server, and the request should be retried later. The resolved image may be either an Image or a Canvas DOM object.

##### Throws:

- DeveloperError : `requestImage` must not be called before the imagery provider is ready.

### Type Definitions

#### Cesium.ArcGisMapServerImageryProvider.ConstructorOptions
Scene/ArcGisMapServerImageryProvider.js 24

Initialization options for the ArcGisMapServerImageryProvider constructor

##### Properties:

Name | Type | Attributes | Default | Description
--- | --- | --- | --- | ---
`url` | Resource | String |  |  | The URL of the ArcGIS MapServer service.
`token` | String | <optional> |  | The ArcGIS token used to authenticate with the ArcGIS MapServer service.
`tileDiscardPolicy` | TileDiscardPolicy | <optional> |  | The policy that determines if a tile is invalid and should be discarded. If this value is not specified, a default `DiscardMissingTileImagePolicy` is used for tiled map servers, and a `NeverTileDiscardPolicy` is used for non-tiled map servers. In the former case, we request tile 0,0 at the maximum tile level and check pixels (0,0), (200,20), (20,200), (80,110), and (160, 130). If all of these pixels are transparent, the discard check is disabled and no tiles are discarded. If any of them have a non-transparent color, any tile that has the same values in these pixel locations is discarded. The end result of these defaults should be correct tile discarding for a standard ArcGIS Server. To ensure that no tiles are discarded, construct and pass a `NeverTileDiscardPolicy` for this parameter.
`usePreCachedTilesIfAvailable` | Boolean | <optional> | true | If true, the server's pre-cached tiles are used if they are available. If false, any pre-cached tiles are ignored and the 'export' service is used.
`layers` | String | <optional> |  | A comma-separated list of the layers to show, or undefined if all layers should be shown.
`enablePickFeatures` | Boolean | <optional> | true | If true, `ArcGisMapServerImageryProvider#pickFeatures` will invoke the Identify service on the MapServer and return the features included in the response. If false, `ArcGisMapServerImageryProvider#pickFeatures` will immediately return undefined (indicating no pickable features) without communicating with the server. Set this property to false if you don't want this provider's features to be pickable. Can be overridden by setting the `ArcGisMapServerImageryProvider#enablePickFeatures` property on the object.
`rectangle` | Rectangle | <optional> | Rectangle.MAX_VALUE | The rectangle of the layer. This parameter is ignored when accessing a tiled layer.
`tilingScheme` | TilingScheme | <optional> | new GeographicTilingScheme() | The tiling scheme to use to divide the world into tiles. This parameter is ignored when accessing a tiled server.
`ellipsoid` | Ellipsoid | <optional> |  | The ellipsoid. If the tilingScheme is specified and used, this parameter is ignored and the tiling scheme's ellipsoid is used instead. If neither parameter is specified, the WGS84 ellipsoid is used.
`credit` | Credit | String | <optional> |  | A credit for the data source, which is displayed on the canvas. This parameter is ignored when accessing a tiled server.
`tileWidth` | Number | <optional> | 256 | The width of each tile in pixels. This parameter is ignored when accessing a tiled server.
`tileHeight` | Number | <optional> | 256 | The height of each tile in pixels. This parameter is ignored when accessing a tiled server.
`maximumLevel` | Number | <optional> |  | The maximum tile level to request, or undefined if there is no maximum. This parameter is ignored when accessing a tiled server.
`options.headers` | Object | <optional> |  | HTTP请求头