feat: adding AudioWorkletNode constructors to Context

Tone/core/context/AudioContext.ts

@@ -1,7 +1,11 @@
 import {
+	IAudioWorkletNodeOptions,
 	AudioContext as stdAudioContext,
+	AudioWorkletNode as stdAudioWorkletNode,
 	OfflineAudioContext as stdOfflineAudioContext,
 } from "standardized-audio-context";
+import { assert } from "../util/Debug";
+import { isDefined } from "../util/TypeCheck";
 
 /**
  * Create a new AudioContext
@@ -75,3 +79,9 @@ export function setAudioContext(context: AnyAudioContext): void {
 		theWindow.TONE_AUDIO_CONTEXT = globalContext;
 	}
 }
+
+export function createAudioWorkletNode(context: AnyAudioContext, name: string, options?: Partial<IAudioWorkletNodeOptions>): AudioWorkletNode {
+	assert(isDefined(stdAudioWorkletNode), "This node only works in a secure context (https or localhost)");
+	// @ts-ignore
+	return new stdAudioWorkletNode(context, name, options);
+}

Tone/core/context/Context.ts

@@ -3,10 +3,10 @@ import { Seconds } from "../type/Units";
 import { isAudioContext } from "../util/AdvancedTypeCheck";
 import { optionsFromArguments } from "../util/Defaults";
 import { Emitter } from "../util/Emitter";
-import { Omit } from "../util/Interface";
+import { noOp, Omit } from "../util/Interface";
 import { Timeline } from "../util/Timeline";
-import { isString } from "../util/TypeCheck";
-import { AnyAudioContext, getAudioContext } from "./AudioContext";
+import { isDefined, isString } from "../util/TypeCheck";
+import { AnyAudioContext, createAudioWorkletNode, getAudioContext } from "./AudioContext";
 import { closeContext, initializeContext } from "./ContextInitialization";
 
 type Transport = import("../clock/Transport").Transport;
@@ -257,6 +257,48 @@ export class Context extends Emitter<"statechange" | "tick"> implements BaseAudi
 		this._destination = d;
 	}
 
+	//--------------------------------------------
+	// AUDIO WORKLET
+	//--------------------------------------------
+
+	/**
+	 * Maps a module name to promise of the addModule method
+	 */
+	private _workletModules: Map<string, Promise<void>> = new Map()
+
+	/**
+	 * Create an audio worklet node from a name and options. The module
+	 * must first be loaded using [[addAudioWorkletModule]]. 
+	 */
+	createAudioWorkletNode(
+		name: string, 
+		options?: Partial<AudioWorkletNodeOptions>
+	): AudioWorkletNode {
+		return createAudioWorkletNode(this.rawContext, name, options);
+	}
+
+	/**
+	 * Add an AudioWorkletProcessor module
+	 * @param url The url of the module
+	 * @param name The name of the module
+	 */
+	async addAudioWorkletModule(url: string, name: string): Promise<void> {
+		this.assert(isDefined(this.rawContext.audioWorklet), "AudioWorkletNode is only available in a secure context (https or localhost)");
+		if (!this._workletModules.has(name)) {
+			this._workletModules.set(name, this.rawContext.audioWorklet.addModule(url));
+		}
+		await this._workletModules.get(name);
+	}
+
+	/**
+	 * Returns a promise which resolves when all of the worklets have been loaded on this context
+	 */
+	protected async workletsAreReady(): Promise<void> {
+		const promises: Promise<void>[] = [];
+		this._workletModules.forEach(promise => promises.push(promise));
+		await Promise.all(promises);
+	}
+
 	//---------------------------
 	// TICKER
 	//---------------------------

Tone/core/context/OfflineContext.ts

@@ -80,7 +80,8 @@ export class OfflineContext extends Context {
 	/**
 	 * Render the output of the OfflineContext
 	 */
-	render(): Promise<AudioBuffer> {
+	async render(): Promise<AudioBuffer> {
+		await this.workletsAreReady();
 		this._renderClock();
 		return this._context.startRendering();
 	}