so://phie

blob: 7cf8ea6533f989f1aee3088e3af43561dd23c2d7 (1361 bytes)[doc][blame][raw]

 1import { scaleCanvas } from './util/canvas.js';
 2
 3export class Game {
 4	constructor(width, height, { fps } = {}) {
 5		this.width = width || 900;
 6		this.height = height || 600;
 7		this.fps = 1000 / (fps || 60);
 8		this.then = Date.now();
 9		this.canvas = document.createElement('canvas');
10		scaleCanvas(this.canvas, this.width, this.height);
11		this.g = this.canvas.getContext('2d');
12		this.events = [];
13		this.sprites = [];
14	}
15	async start() {
16		for(const sprite of this.sprites) {
17			await sprite.load();
18		}
19		requestAnimationFrame(this.loop.bind(this));
20		this.update();
21		this.render(this.g);
22	}
23	loop() {
24		requestAnimationFrame(this.loop.bind(this));
25		this.now = Date.now();
26		this.elapsed = this.now - this.then;
27		if(this.elapsed > this.fps) {
28			this.then = this.now - (this.elapsed % this.fps);
29			for(const event of this.events) {
30				if(this['on' + event.type]) {
31					this['on' + event.type](event);
32				}
33			}
34			this.update();
35			this.render(this.g);
36			this.events.length = 0;
37		}
38	}
39	update() {
40		// nothing
41	}
42	render() {
43		this.g.clearRect(0, 0, this.width, this.height);
44	}
45	resize(width, height) {
46		this.width = width;
47		this.height = height;
48		scaleCanvas(this.canvas, this.width, this.height);
49	}
50	bindEvent(element, type) {
51		element['on' + type] = event => this.events.push(event);
52	}
53	loadSprite(sprite) {
54		this.sprites.push(sprite);
55	}
56}