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

ImageSource

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.

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.