kotlin-browser/web.canvas/OffscreenCanvas

OffscreenCanvas

open class OffscreenCanvas( var width: UInt53, var height: UInt53) : EventTarget, CanvasImageSource, TexImageSource, GPUCopyExternalImageSource, Transferable(source)

When using the canvas element or the Canvas API, rendering, animation, and user interaction usually happen on the main execution thread of a web application.

MDN Reference

Constructors

OffscreenCanvas

constructor(width: UInt53, height: UInt53)

Properties

contextLostEvent

val contextLostEvent: EventInstance<Event, OffscreenCanvas, OffscreenCanvas>

MDN Reference

contextRestoredEvent

val contextRestoredEvent: EventInstance<Event, OffscreenCanvas, OffscreenCanvas>

MDN Reference

height

var height: UInt53

These attributes return the dimensions of the OffscreenCanvas object's bitmap.

oncontextlost

var oncontextlost: EventHandler<Event, OffscreenCanvas, OffscreenCanvas>?

MDN Reference

oncontextrestored

var oncontextrestored: EventHandler<Event, OffscreenCanvas, OffscreenCanvas>?

MDN Reference

width

var width: UInt53

These attributes return the dimensions of the OffscreenCanvas object's bitmap.

Functions

convertToBlob

suspend fun convertToBlob(options: ImageEncodeOptions = definedExternally): Blob

Returns a promise that will fulfill with a new Blob object representing a file containing the image in the OffscreenCanvas object.

convertToBlobAsync

fun convertToBlobAsync(options: ImageEncodeOptions = definedExternally): Promise<Blob>

dispatchEvent

fun dispatchEvent(event: Event): Boolean

getContext

fun <T : OffscreenRenderingContext, O : JsAny> getContext(contextId: RenderingContextId<T, O>, options: O? = definedExternally): T?

Returns an object that exposes an API for drawing on the OffscreenCanvas object. contextId specifies the desired API: "2d", "bitmaprenderer", "webgl", or "webgl2". options is handled by that API.

transferToImageBitmap

fun transferToImageBitmap(): ImageBitmap

Returns a newly created ImageBitmap object with the image in the OffscreenCanvas object. The image in the OffscreenCanvas object is replaced with a new blank image.

when

fun <T : Event> when(type: EventType<T>, options: ObservableEventListenerOptions?): Observable<T>