Class: RasterSource

ol/source/Raster~RasterSource 


import RasterSource from 'ol/source/Raster.js';

A source that transforms data from any number of input sources using an Operation function to transform input pixel values into output pixel values.

new RasterSource(options)

source/Raster.js, line 634
Name Type Description
sources Array.<(module:ol/source/Source~Source|module:ol/layer/Layer~Layer)>

Input sources or layers. Most sources and layers are rendered to an image and read back as RGBA pixels. A DataTileSource (such as a GeoTIFFSource) provided directly as a source preserves the data type and precision of the tiles (e.g. Float32Array values are passed to the operation unchanged rather than clamped to bytes), and the operation receives all of the source's bands per pixel. To render a data tile source through a layer instead (for example a WebGLTileLayer that styles it to RGBA), pass the layer rather than the source. For data tile inputs, there are some limitations: only 'pixel' operations are supported (an 'image' operation requires image inputs); resampling to the view resolution uses nearest neighbor regardless of the interpolate option; the tile data must match the tile grid pixel for pixel, so sources with a gutter are not supported.
operation Operation | undefined

Raster operation. The operation will be called with data from input sources and the output will be assigned to the raster source.
interpolate boolean (defaults to true)

Use interpolated values when resampling. By default, linear interpolation is used when resampling. Set to false to use the nearest neighbor instead.
lib Object | undefined

Functions that will be made available to operations run in a worker.
threads number | undefined

By default, operations will be run in a single worker thread. To avoid using workers altogether, set threads: 0. For pixel operations, operations can be run in multiple worker threads. Note that there is additional overhead in transferring data to multiple workers, and that depending on the user's system, it may not be possible to parallelize the work.
operationType RasterOperationType (defaults to 'pixel')

Operation type. Supported values are 'pixel' and 'image'. By default, 'pixel' operations are assumed, and operations will be called with an array of pixels from input sources. If set to 'image', operations will be called with an array of ImageData objects from input sources.
resolutions Array.<number> | null | undefined

Resolutions. If specified, raster operations will only be run at the given resolutions. By default, the resolutions of the first source with resolutions specified will be used, if any. Set to null to use any view resolution instead.
Fires:

Extends

Methods

changed() inherited

Observable.js, line 72

Increases the revision counter and dispatches a 'change' event.

dispatchEvent(event){boolean | undefined} inherited

events/Target.js, line 85

Dispatches an event and calls all listeners listening for events of this type. The event parameter can either be a string or an Object with a type property.

Name Type Description
event BaseEvent | string

Event object.
Returns:
false if anyone called preventDefault on the event object or if any of the listeners returned false.

dispose()

source/Raster.js, line 1171

Clean up and unregister the worker.

get(key){*} inherited

Object.js, line 136

Gets a value.

Name Type Description
key string

Key name.
Returns:
Value.

getAttributions(){Attribution} inherited

source/Source.js, line 135

Get the attribution function for the source.

Returns:
Attribution function.

getAttributionsCollapsible(){boolean} inherited

source/Source.js, line 143
Returns:
Attributions are collapsible.

getData(coordinate){Array.<(Array.<number>|Uint8ClampedArray|Uint8Array|Float32Array)> | null}

source/Raster.js, line 973

Get the input source values at a coordinate, as the operation receives them: one array of values per input source, in source order. Data tile inputs yield their native band values (in the tiles' array type); other inputs yield the [r, g, b, a] values read back from their layer renderer. Returns null if the source has not been rendered at least once, or if an input is not yet available.

Name Type Description
coordinate Coordinate

The coordinate, in the view projection.
Returns:
The values per input source.

getKeys(){Array.<string>} inherited

Object.js, line 149

Get a list of object property names.

Returns:
List of property names.

getProjection(){Projection | null} inherited

source/Source.js, line 152

Get the projection of the source.

Returns:
Projection.

getProperties(){NoInfer.<Properties>} inherited

Object.js, line 158

Get an object of all property names and values.

Returns:
Object.

getRevision(){number} inherited

Observable.js, line 83

Get the version number for this object. Each time the object is modified, its version number will be incremented.

Returns:
Revision.

getState(){State} inherited

source/Source.js, line 207

Get the state of the source, see State for possible states.

Returns:
State.

on(type, listener){EventsKey | Array<EventsKey>} inherited

Observable.js, line 156

Listen for a certain type of event.

Name Type Description
type string | Array.<string>

The event type or array of event types.
listener function

The listener function.
Returns:
Unique key for the listener. If called with an array of event types as the first argument, the return will be an array of keys.

once(type, listener){EventsKey | Array<EventsKey>} inherited

Observable.js, line 168

Listen once for a certain type of event.

Name Type Description
type string | Array.<string>

The event type or array of event types.
listener function

The listener function.
Returns:
Unique key for the listener. If called with an array of event types as the first argument, the return will be an array of keys.

refresh() inherited

source/Source.js, line 229

Refreshes the source. The source will be cleared, and data from the server will be reloaded.

set(key, value, silent) inherited

Object.js, line 218

Sets a value.

Name Type Description
key string

Key name.
value *

Value.
silent boolean | undefined

Update without triggering an event.

setAttributions(attributions) inherited

source/Source.js, line 240

Set the attributions of the source.

Name Type Description
attributions AttributionLike | undefined

Attributions. Can be passed as string, Array<string>, Attribution, or undefined.

setOperation(operation, lib)

source/Raster.js, line 802

Set the operation.

Name Type Description
operation Operation

New operation.
lib Object.<string, function()> | undefined

Functions that will be available to operations run in a worker.

setProperties(values, silent) inherited

Object.js, line 241

Sets a collection of key-value pairs. Note that this changes any existing properties and adds new ones (it does not remove any existing properties).

Name Type Description
values Partial.<NoInfer.<Properties>>

Values.
silent boolean | undefined

Update without triggering an event.

un(type, listener) inherited

Observable.js, line 177

Unlisten for a certain type of event.

Name Type Description
type string | Array.<string>

The event type or array of event types.
listener function

The listener function.

unset(key, silent) inherited

Object.js, line 265

Unsets a property.

Name Type Description
key string

Key name.
silent boolean | undefined

Unset without triggering an event.