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Module

x/evt/lib/index.ts>dom.OffscreenCanvas

💧EventEmitter's typesafe replacement
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interface dom.OffscreenCanvas
implements EventTarget
import { type dom } from "https://deno.land/x/evt@v2.4.11/lib/index.ts";
const { OffscreenCanvas } = dom;

Properties

height: number

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

They can be set, to replace the bitmap with a new, transparent black bitmap of the specified dimensions (effectively resizing it).

width: number

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

They can be set, to replace the bitmap with a new, transparent black bitmap of the specified dimensions (effectively resizing it).

Methods

convertToBlob(options?: ImageEncodeOptions): Promise<Blob>

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

The argument, if provided, is a dictionary that controls the encoding options of the image file to be created. The type field specifies the file format and has a default value of "image/png"; that type is also used if the requested type isn't supported. If the image format supports variable quality (such as "image/jpeg"), then the quality field is a number in the range 0.0 to 1.0 inclusive indicating the desired quality level for the resulting image.

getContext(contextId: "2d", options?: CanvasRenderingContext2DSettings): OffscreenCanvasRenderingContext2D | null

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.

This specification defines the "2d" context below, which is similar but distinct from the "2d" context that is created from a canvas element. The WebGL specifications define the "webgl" and "webgl2" contexts. [WEBGL]

Returns null if the canvas has already been initialized with another context type (e.g., trying to get a "2d" context after getting a "webgl" context).

getContext(contextId: "bitmaprenderer", options?: ImageBitmapRenderingContextSettings): ImageBitmapRenderingContext | null
getContext(contextId: "webgl", options?: WebGLContextAttributes): WebGLRenderingContext | null
getContext(contextId: "webgl2", options?: WebGLContextAttributes): WebGL2RenderingContext | null
getContext(contextId: OffscreenRenderingContextId, options?: any): OffscreenRenderingContext | null
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.