first app vibe

app/node_modules/three/examples/jsm/utils/WorkerPool.js

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+/**
+ * A simple pool for managing Web Workers.
+ *
+ * @three_import import { WorkerPool } from 'three/addons/utils/WorkerPool.js';
+ */
+export class WorkerPool {
+
+	/**
+	 * Constructs a new Worker pool.
+	 *
+	 * @param {number} [pool=4] - The size of the pool.
+	 */
+	constructor( pool = 4 ) {
+
+		/**
+		 * The size of the pool.
+		 *
+		 * @type {number}
+		 * @default 4
+		 */
+		this.pool = pool;
+
+		/**
+		 * A message queue.
+		 *
+		 * @type {Array<Object>}
+		 */
+		this.queue = [];
+
+		/**
+		 * An array of Workers.
+		 *
+		 * @type {Array<Worker>}
+		 */
+		this.workers = [];
+
+		/**
+		 * An array with resolve functions for messages.
+		 *
+		 * @type {Array<Function>}
+		 */
+		this.workersResolve = [];
+
+		/**
+		 * The current worker status.
+		 *
+		 * @type {number}
+		 */
+		this.workerStatus = 0;
+
+		/**
+		 * A factory function for creating workers.
+		 *
+		 * @type {?Function}
+		 */
+		this.workerCreator = null;
+
+	}
+
+	_initWorker( workerId ) {
+
+		if ( ! this.workers[ workerId ] ) {
+
+			const worker = this.workerCreator();
+			worker.addEventListener( 'message', this._onMessage.bind( this, workerId ) );
+			this.workers[ workerId ] = worker;
+
+		}
+
+	}
+
+	_getIdleWorker() {
+
+		for ( let i = 0; i < this.pool; i ++ )
+			if ( ! ( this.workerStatus & ( 1 << i ) ) ) return i;
+
+		return - 1;
+
+	}
+
+	_onMessage( workerId, msg ) {
+
+		const resolve = this.workersResolve[ workerId ];
+		resolve && resolve( msg );
+
+		if ( this.queue.length ) {
+
+			const { resolve, msg, transfer } = this.queue.shift();
+			this.workersResolve[ workerId ] = resolve;
+			this.workers[ workerId ].postMessage( msg, transfer );
+
+		} else {
+
+			this.workerStatus ^= 1 << workerId;
+
+		}
+
+	}
+
+	/**
+	 * Sets a function that is responsible for creating Workers.
+	 *
+	 * @param {Function} workerCreator - The worker creator function.
+	 */
+	setWorkerCreator( workerCreator ) {
+
+		this.workerCreator = workerCreator;
+
+	}
+
+	/**
+	 * Sets the Worker limit
+	 *
+	 * @param {number} pool - The size of the pool.
+	 */
+	setWorkerLimit( pool ) {
+
+		this.pool = pool;
+
+	}
+
+	/**
+	 * Post a message to an idle Worker. If no Worker is available,
+	 * the message is pushed into a message queue for later processing.
+	 *
+	 * @param {Object} msg - The message.
+	 * @param {Array<ArrayBuffer>} transfer - An array with array buffers for data transfer.
+	 * @return {Promise} A Promise that resolves when the message has been processed.
+	 */
+	postMessage( msg, transfer ) {
+
+		return new Promise( ( resolve ) => {
+
+			const workerId = this._getIdleWorker();
+
+			if ( workerId !== - 1 ) {
+
+				this._initWorker( workerId );
+				this.workerStatus |= 1 << workerId;
+				this.workersResolve[ workerId ] = resolve;
+				this.workers[ workerId ].postMessage( msg, transfer );
+
+			} else {
+
+				this.queue.push( { resolve, msg, transfer } );
+
+			}
+
+		} );
+
+	}
+
+	/**
+	 * Terminates all Workers of this pool. Call this  method whenever this
+	 * Worker pool is no longer used in your app.
+	 */
+	dispose() {
+
+		this.workers.forEach( ( worker ) => worker.terminate() );
+		this.workersResolve.length = 0;
+		this.workers.length = 0;
+		this.queue.length = 0;
+		this.workerStatus = 0;
+
+	}
+
+}