Interface OffscreenCanvas

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

interface OffscreenCanvas {
    height: number;
    oncontextlost: ((this: OffscreenCanvas, ev: Event) => any) | null;
    oncontextrestored: ((this: OffscreenCanvas, ev: Event) => any) | null;
    width: number;
    addEventListener<K extends keyof OffscreenCanvasEventMap>(
        type: K,
        listener: (this: OffscreenCanvas, ev: OffscreenCanvasEventMap[K]) => any,
        options?: boolean | AddEventListenerOptions,
    ): void;
    addEventListener(
        type: string,
        listener: EventListenerOrEventListenerObject,
        options?: boolean | AddEventListenerOptions,
    ): void;
    convertToBlob(options?: ImageEncodeOptions): Promise<Blob>;
    dispatchEvent(event: Event): boolean;
    getContext(
        contextId: "2d",
        options?: any,
    ): OffscreenCanvasRenderingContext2D | null;
    getContext(
        contextId: "bitmaprenderer",
        options?: any,
    ): ImageBitmapRenderingContext | null;
    getContext(contextId: "webgl", options?: any): WebGLRenderingContext | null;
    getContext(
        contextId: "webgl2",
        options?: any,
    ): WebGL2RenderingContext | null;
    getContext(
        contextId: OffscreenRenderingContextId,
        options?: any,
    ): OffscreenRenderingContext | null;
    removeEventListener<K extends keyof OffscreenCanvasEventMap>(
        type: K,
        listener: (this: OffscreenCanvas, ev: OffscreenCanvasEventMap[K]) => any,
        options?: boolean | EventListenerOptions,
    ): void;
    removeEventListener(
        type: string,
        listener: EventListenerOrEventListenerObject,
        options?: boolean | EventListenerOptions,
    ): void;
    transferToImageBitmap(): ImageBitmap;
}

Hierarchy

EventTarget
- OffscreenCanvas

Index

Properties

height oncontextlost oncontextrestored width

Methods

addEventListener convertToBlob dispatchEvent getContext removeEventListener transferToImageBitmap

Properties

height

height: number

The height property returns and sets the height of an OffscreenCanvas object.

MDN Reference

oncontextlost

oncontextlost: ((this: OffscreenCanvas, ev: Event) => any) | null

MDN Reference

oncontextrestored

oncontextrestored: ((this: OffscreenCanvas, ev: Event) => any) | null

MDN Reference

width

width: number

The width property returns and sets the width of an OffscreenCanvas object.

MDN Reference

Methods

addEventListener

addEventListener<K extends keyof OffscreenCanvasEventMap>(
    type: K,
    listener: (this: OffscreenCanvas, ev: OffscreenCanvasEventMap[K]) => any,
    options?: boolean | AddEventListenerOptions,
): void
The addEventListener() method of the EventTarget interface sets up a function that will be called whenever the specified event is delivered to the target.

MDN Reference
Type Parameters
- K extends keyof OffscreenCanvasEventMap
Parameters
- type: K
- listener: (this: OffscreenCanvas, ev: OffscreenCanvasEventMap[K]) => any
- Optionaloptions: boolean | AddEventListenerOptions
Returns void
Overrides EventTarget.addEventListener
- Defined in node_modules/typescript/lib/lib.dom.d.ts:22406
addEventListener(
    type: string,
    listener: EventListenerOrEventListenerObject,
    options?: boolean | AddEventListenerOptions,
): void
The addEventListener() method of the EventTarget interface sets up a function that will be called whenever the specified event is delivered to the target.

MDN Reference
Parameters
- type: string
- listener: EventListenerOrEventListenerObject
- Optionaloptions: boolean | AddEventListenerOptions
Returns void
Overrides EventTarget.addEventListener
- Defined in node_modules/typescript/lib/lib.dom.d.ts:22407

convertToBlob

convertToBlob(options?: ImageEncodeOptions): Promise<Blob>
The OffscreenCanvas.convertToBlob() method creates a Blob object representing the image contained in the canvas.

MDN Reference
Parameters
- Optionaloptions: ImageEncodeOptions
Returns Promise<Blob>
- Defined in node_modules/typescript/lib/lib.dom.d.ts:22389

dispatchEvent

dispatchEvent(event: Event): boolean
The dispatchEvent() method of the EventTarget sends an Event to the object, (synchronously) invoking the affected event listeners in the appropriate order.

MDN Reference
Parameters
- event: Event
Returns boolean
Inherited from EventTarget.dispatchEvent
- Defined in node_modules/typescript/lib/lib.dom.d.ts:11575

getContext

getContext(
contextId: "2d",
options?: any,
): OffscreenCanvasRenderingContext2D | null
The OffscreenCanvas.getContext() method returns a drawing context for an offscreen canvas, or null if the context identifier is not supported, or the offscreen canvas has already been set to a different context mode.

MDN Reference
Parameters
- contextId: "2d"
- Optionaloptions: any
Returns OffscreenCanvasRenderingContext2D | null
- Defined in node_modules/typescript/lib/lib.dom.d.ts:22395
getContext(
contextId: "bitmaprenderer",
options?: any,
): ImageBitmapRenderingContext | null
Parameters
- contextId: "bitmaprenderer"
- Optionaloptions: any
Returns ImageBitmapRenderingContext | null
- Defined in node_modules/typescript/lib/lib.dom.d.ts:22396
getContext(contextId: "webgl", options?: any): WebGLRenderingContext | null
Parameters
- contextId: "webgl"
- Optionaloptions: any
Returns WebGLRenderingContext | null
- Defined in node_modules/typescript/lib/lib.dom.d.ts:22397
getContext(contextId: "webgl2", options?: any): WebGL2RenderingContext | null
Parameters
- contextId: "webgl2"
- Optionaloptions: any
Returns WebGL2RenderingContext | null
- Defined in node_modules/typescript/lib/lib.dom.d.ts:22398
getContext(
contextId: OffscreenRenderingContextId,
options?: any,
): OffscreenRenderingContext | null
Parameters
- contextId: OffscreenRenderingContextId
- Optionaloptions: any
Returns OffscreenRenderingContext | null
- Defined in node_modules/typescript/lib/lib.dom.d.ts:22399

removeEventListener

removeEventListener<K extends keyof OffscreenCanvasEventMap>(
    type: K,
    listener: (this: OffscreenCanvas, ev: OffscreenCanvasEventMap[K]) => any,
    options?: boolean | EventListenerOptions,
): void
The removeEventListener() method of the EventTarget interface removes an event listener previously registered with EventTarget.addEventListener() from the target.

MDN Reference
Type Parameters
- K extends keyof OffscreenCanvasEventMap
Parameters
- type: K
- listener: (this: OffscreenCanvas, ev: OffscreenCanvasEventMap[K]) => any
- Optionaloptions: boolean | EventListenerOptions
Returns void
Overrides EventTarget.removeEventListener
- Defined in node_modules/typescript/lib/lib.dom.d.ts:22408
removeEventListener(
    type: string,
    listener: EventListenerOrEventListenerObject,
    options?: boolean | EventListenerOptions,
): void
The removeEventListener() method of the EventTarget interface removes an event listener previously registered with EventTarget.addEventListener() from the target.

MDN Reference
Parameters
- type: string
- listener: EventListenerOrEventListenerObject
- Optionaloptions: boolean | EventListenerOptions
Returns void
Overrides EventTarget.removeEventListener
- Defined in node_modules/typescript/lib/lib.dom.d.ts:22409

transferToImageBitmap

transferToImageBitmap(): ImageBitmap
The OffscreenCanvas.transferToImageBitmap() method creates an ImageBitmap object from the most recently rendered image of the OffscreenCanvas.

MDN Reference

Returns ImageBitmap
- Defined in node_modules/typescript/lib/lib.dom.d.ts:22405

Interface OffscreenCanvas

Hierarchy

Index

Properties

Methods

Properties

height

oncontextlost

oncontextrestored

width

Methods

addEventListener

Type Parameters

Parameters

Returns void

Parameters

Returns void

convertToBlob

Parameters

Returns Promise<Blob>

dispatchEvent

Parameters

Returns boolean

getContext

Parameters

Returns OffscreenCanvasRenderingContext2D | null

Parameters

Returns ImageBitmapRenderingContext | null

Parameters

Returns WebGLRenderingContext | null

Parameters

Returns WebGL2RenderingContext | null

Parameters

Returns OffscreenRenderingContext | null

removeEventListener

Type Parameters

Parameters

Returns void

Parameters

Returns void

transferToImageBitmap

Returns ImageBitmap

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