JavaScript Canvas实现噪点滤镜回忆童年电视雪花屏

import * as PIXI from "pixi.js"
const GAME_WIDTH = 800;
const GAME_HEIGHT = 600;
export default class Game {
    constructor(el) {
        this.isOpen = false;
        return this.init(el)
    }
    init(el) {
        this.app = new PIXI.Application({
            width: GAME_WIDTH,
            height: GAME_HEIGHT,
            backgroundColor: 0x000000,
            antialias: true,
            clearBeforeRender: true,
            antialias: true,
            autoDensity: true,
            resolution: window.devicePixelRatio || 1,
        });
        el.appendChild(this.app.view);
        this.loader = new PIXI.Loader();
        this.loader
            .add("tv", "./assets/SnowflakeScreen/TV.png")
            .load(this.render.bind(this))
        return this;
    }
    render(loader, resources) {
        // 渲染
        this.resources = resources; 
        // 创建容器
        this.container = new PIXI.Container();
        this.container.interactive = true;
        this.container.buttonMode = true;
        this.app.stage.addChild(this.container);
        this.tv = this.drawTV();
        this.container.addChild(this.tv);
    }
    drawTV() {
        // 绘制电视机
        let tv = PIXI.Sprite.from(this.resources.tv.texture);
        tv.anchor.set(0.5);
        tv.position.set(GAME_WIDTH / 2, GAME_HEIGHT / 2)
        tv.scale.set(.7, .7)
        tv.zIndex = 9;
        return tv;
    }
}

export default class Game {
	render(loader, resources) {
        // 渲染
        // ...
        this.noise = this.drawNoise()
        this.noise.visible = true
        this.container.addChild(this.noise);
    }
    drawNoise() {
        let noise = new PIXI.Graphics()
        noise.beginFill(0xffffff, .55)
        noise.drawRect(105, 100, 450, 360)
        noise.zIndex = 1
        return noise;
    }
}

this.noise.filters = [new PIXI.filters.NoiseFilter(.6, Math.random())]

export default class Game {
	render(loader, resources) {
        // 渲染
        // ...
        this.noise.filters = []
        this.app.ticker.add(this.step.bind(this));
    }   
    step() {
        this.noise.filters = [new PIXI.filters.NoiseFilter(.6, Math.random())]
    }
}

export default class Game {
	render(loader, resources) {
        // 渲染
        // ...
       	this.video = this.drawVideo()
        this.container.addChild(this.video);      
    }    
	drawVideo() {
        let textureList = []
        for (let i = 1; i <= 28; i++) {
            let texture = PIXI.Texture.from(`assets/SnowflakeScreen/video/ezgif-frame-${(i + "").padStart(3, 0)}.jpg`);
            textureList.push(texture);
        };
        const video = new PIXI.AnimatedSprite(textureList);
        video.anchor.set(.5, .5)
        video.position.set(GAME_WIDTH / 2, GAME_HEIGHT / 2 - 10)
        video.scale.set(.48, .48)
        video.loop = false;
        video.animationSpeed = .16
        return video;
    }
}

export default class Game {
	render(loader, resources) {
        // 渲染
        // ...
        this.video.visible = false;
        this.video.onComplete = () => {
            this.video.visible = false;
            this.noise.visible = true
        }
        this.container.on('pointerdown', (e) => {
            if(!this.isOpen){
                this.isOpen = true;
                this.video.visible = true;
                this.noise.visible = false
                this.video.gotoAndPlay(0)
            }
            else{
                this.isOpen = false;
                this.noise.filters.length = 0
                this.video.visible = false;
                this.noise.visible = true;
            }
        })
    }
    step() {
        if(!this.isOpen) return;
        this.noise.filters = [new PIXI.filters.NoiseFilter(.6, Math.random())]
    }
}