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CanvasSource

A data source containing the contents of an HTML canvas. See CanvasSourceSpecification for detailed documentation of options.

Example

// add to map
map.addSource('some id', {
   type: 'canvas',
   canvas: 'idOfMyHTMLCanvas',
   animate: true,
   coordinates: [
       [-76.54, 39.18],
       [-76.52, 39.18],
       [-76.52, 39.17],
       [-76.54, 39.17]
   ]
});

// update
let mySource = map.getSource('some id');
mySource.setCoordinates([
    [-76.54335737228394, 39.18579907229748],
    [-76.52803659439087, 39.1838364847587],
    [-76.5295386314392, 39.17683392507606],
    [-76.54520273208618, 39.17876344106642]
]);

map.removeSource('some id');  // remove

Extends

Methods

getCanvas()

getCanvas(): HTMLCanvasElement

Returns the HTML canvas element.

Returns

HTMLCanvasElement

The HTML canvas element.

Defined in

src/source/canvas_source.ts:147


listens()

listens(type: string): boolean

Returns a true if this instance of Evented or any forwardeed instances of Evented have a listener for the specified type.

Parameters

Parameter Type Description
type string The event type

Returns

boolean

true if there is at least one registered listener for specified event type, false otherwise

Inherited from

ImageSource.listens

Defined in

src/util/evented.ts:161


loadTile()

loadTile(tile: Tile): Promise<void>

This method does the heavy lifting of loading a tile. In most cases it will defer the work to the relevant worker source.

Parameters

Parameter Type Description
tile Tile The tile to load

Returns

Promise<void>

Inherited from

ImageSource.loadTile

Defined in

src/source/image_source.ts:281


loaded()

loaded(): boolean

True if the source is loaded, false otherwise.

Returns

boolean

Inherited from

ImageSource.loaded

Defined in

src/source/image_source.ts:155


off()

off(type: string, listener: Listener): CanvasSource

Removes a previously registered event listener.

Parameters

Parameter Type Description
type string The event type to remove listeners for.
listener Listener The listener function to remove.

Returns

CanvasSource

Inherited from

ImageSource.off

Defined in

src/util/evented.ts:86


on()

on(type: string, listener: Listener): this

Adds a listener to a specified event type.

Parameters

Parameter Type Description
type string The event type to add a listen for.
listener Listener The function to be called when the event is fired. The listener function is called with the data object passed to fire, extended with target and type properties.

Returns

this

Inherited from

ImageSource.on

Defined in

src/util/evented.ts:73


once()

once(type: string, listener?: Listener): Promise<any> | CanvasSource

Adds a listener that will be called only once to a specified event type.

The listener will be called first time the event fires after the listener is registered.

Parameters

Parameter Type Description
type string The event type to listen for.
listener? Listener The function to be called when the event is fired the first time.

Returns

Promise<any> | CanvasSource

this or a promise if a listener is not provided

Inherited from

ImageSource.once

Defined in

src/util/evented.ts:102


setCoordinates()

setCoordinates(coordinates: Coordinates): this

Sets the image's coordinates and re-renders the map.

Parameters

Parameter Type Description
coordinates Coordinates Four geographical coordinates, represented as arrays of longitude and latitude numbers, which define the corners of the image. The coordinates start at the top left corner of the image and proceed in clockwise order. They do not have to represent a rectangle.

Returns

this

Inherited from

ImageSource.setCoordinates

Defined in

src/source/image_source.ts:207


setEventedParent()

setEventedParent(parent?: Evented, data?: any): CanvasSource

Bubble all events fired by this instance of Evented to this parent instance of Evented.

Parameters

Parameter Type
parent? Evented
data? any

Returns

CanvasSource

Inherited from

ImageSource.setEventedParent

Defined in

src/util/evented.ts:172


updateImage()

updateImage(options: UpdateImageOptions): this

Updates the image URL and, optionally, the coordinates. To avoid having the image flash after changing, set the raster-fade-duration paint property on the raster layer to 0.

Parameters

Parameter Type Description
options UpdateImageOptions The options object.

Returns

this

Inherited from

ImageSource.updateImage

Defined in

src/source/image_source.ts:165

Properties

id

id: string

The id for the source. Must not be used by any existing source.

Inherited from

ImageSource.id

Defined in

src/source/image_source.ts:90


maxzoom

maxzoom: number

The maximum zoom level for the source.

Inherited from

ImageSource.maxzoom

Defined in

src/source/image_source.ts:92


minzoom

minzoom: number

The minimum zoom level for the source.

Inherited from

ImageSource.minzoom

Defined in

src/source/image_source.ts:91


pause()

pause: () => void

Disables animation. The map will display a static copy of the canvas image.

Returns

void

Defined in

src/source/canvas_source.ts:81


play()

play: () => void

Enables animation. The image will be copied from the canvas to the map on each frame.

Returns

void

Defined in

src/source/canvas_source.ts:77


tileSize

tileSize: number

The tile size for the source.

Inherited from

ImageSource.tileSize

Defined in

src/source/image_source.ts:93