@needle-tools/engine/src/engine/engine_coroutine.ts

Needle Engine is a web-based runtime for 3D apps. It runs on your machine for development with great integrations into editors like Unity or Blender - and can be deployed onto any device! It is flexible, extensible and networking and XR are built-in.

import { Context } from "./engine_setup.js";

/** Wait for a number of seconds to pass.
 * @param seconds
 * @param context
 * @returns Generator function
 * @example
 * ```typescript
 * function *myCoroutineFunction() {
 *   yield* WaitForSeconds(1);
 * }
 * ``` 
 */
export function* WaitForSeconds(seconds: number, context: Context | null = null) {
    const time = context ? context.time : Context.Current.time;
    const start = time.time;
    while(time.time - start < seconds) {
        yield;
    }
}

/** Wait for a number of frames to pass.
 * @param frames
 * @returns Generator function
 * @example
 * ```typescript
 * function *myCoroutineFunction() {
 *    yield* WaitForFrames(10); 
 * }
 * ```
 */
export function* WaitForFrames(frames: number) {
    for(let i = 0; i < frames; i++) {
        yield;
    }
}

/** Wait for a promise to resolve.
 * @param promise
 * @returns Generator function
 * @example
 * ```typescript
 * function *myCoroutineFunction() {
 *   yield* WaitForPromise(fetch("https://jsonplaceholder.typicode.com/todos/1"));
 * }
 * ```
 */
export function* WaitForPromise(promise: Promise<any>) {
    let isRunning = true;
    promise.then(() => isRunning = false);
    promise.catch(() => isRunning = false);
    while (isRunning) {
        yield;
    }
}