# Module: ol/source/mapserver

This documentation is for OpenLayers v10.9.0. The latest is v.

## ol/source/mapserver

### Functions

#### createLoader(options){ImageObjectPromiseLoader}

source/mapserver.js, line 61

      import {createLoader} from 'ol/source/mapserver';

  Creates a loader for MapServer images generated using the CGI interface, which predates OGC services. It is strongly recommended to configure MapServer to use WMS, and use the WMS createLoader.

  Name | Type | Description
  --- | --- | ---
  `url` | string | The MapServer url.
  `crossOrigin` | null | string | undefined | The `crossOrigin` attribute for loaded images. Note that you must provide a `crossOrigin` value if you want to access pixel data with the Canvas renderer. See https://developer.mozilla.org/en-US/docs/Web/HTML/CORS_enabled_image for more detail.
  `referrerPolicy` | ReferrerPolicy | undefined | The `referrerPolicy` property for loaded images. the image from the remote server.
  `ratio` | number (defaults to 1) | Ratio. `1` means image requests are the size of the map viewport, `2` means twice the width and height of the map viewport, and so on. Must be `1` or higher.
  `params` | Object | undefined | Additional query parameters.
  `load` | function | undefined | Function to perform loading of the image. Receives the created `HTMLImageElement` and the desired `src` as argument and returns a promise resolving to the loaded or decoded image. Default is `decode`.

  ##### Returns:

  MapServer image.

### Type Definitions

#### LoaderOptions{Object}

  ##### Properties:

  Name | Type | Description
  --- | --- | ---
  `url` | string | The MapServer url.
  `crossOrigin` | null | string | undefined | The `crossOrigin` attribute for loaded images. Note that you must provide a `crossOrigin` value if you want to access pixel data with the Canvas renderer. See https://developer.mozilla.org/en-US/docs/Web/HTML/CORS_enabled_image for more detail.
  `referrerPolicy` | ReferrerPolicy | undefined | The `referrerPolicy` property for loaded images. the image from the remote server.
  `ratio` | number (defaults to 1) | Ratio. `1` means image requests are the size of the map viewport, `2` means twice the width and height of the map viewport, and so on. Must be `1` or higher.
  `params` | Object | undefined | Additional query parameters.
  `load` | function | undefined | Function to perform loading of the image. Receives the created `HTMLImageElement` and the desired `src` as argument and returns a promise resolving to the loaded or decoded image. Default is `decode`.