Webleb - Snippets de Código - o jogo de bola por diversão (pelo Sr.)

// call the canvas 
let canvas = document.querySelector("canvas")
// the screen
canvas.width = window.innerWidth ; 
canvas.height = window.innerHeight ; 
// create the 2d screen 
let c = canvas.getContext("2d");

class ball{
    // that is the variable
    constructor(x , y){
        this.baseR = 10
        this.r = this.baseR
        this.r  = (Math.random()) * 20 ;
        this.x  = x || randomSetInrFromInterval(this.r , window.innerWidth - this.r);
        this.y  = y || randomSetInrFromInterval(this.r , window.innerHeight - this.r);
        this.vx = (Math.random() - 0.5) * 5 ;
        this.vy = (Math.random() - 0.5) * 5 ;
        this.color = `rgb(${(Math.random() * 255)} , ${(Math.random() * 255)} , ${(Math.random() * 255)})`
        this.draw()
    }
    // the roll for create the circle 
    draw(){
        c.beginPath();
        c.arc(this.x,this.y,this.r,0,Math.PI * 2);
        c.fillStyle = this.color
        c.fill()
    }
    // the roll for ball can not out the screen 
    update(){
        if(this.x+this.r > window.innerWidth || this.x-this.r < 0){
            this.vx = -this.vx
        }
        if(this.y+this.r > window.innerHeight || this.y-this.r < 0){
            this.vy = -this.vy
        }
        this.x += this.vx
        this.y += this.vy
        this.draw()
    }
}

// the loop for create any ball 
let balls = [] ;
for(let i = 0 ; i<100 ; i++){
    balls.push(new ball())
}
// the scroll ball , create a ball
function animate(){
    c.clearRect(0,0,window.innerWidth , window.innerHeight);
    balls.forEach(ball =>{
        ball.update()
    })
    requestAnimationFrame(animate)
}
 // that is the function for create the ball when i click on the screen
window.addEventListener("click" , (e)=>{
    balls.push(new ball(e.clientX , e.clientY))
})

window. addEventListener("mousemove" ,(e)=>{
    balls.forEach(ball=>{
        let distance = Math.sqrt(Math.pow(e.clientX - ball.x,2) + Math.pow(e.clientY - ball.y,2))
        if(distance < 100 && ball.r < ball.baseR * 4){
            ball.r += 1
        }else if(ball.r > ball.baseR){
            ball.r -= 1
        }
    })
})

window.addEventListener("resize" , ()=>{
    canvas.width = window.innerWidth ; 
    canvas.height = window.innerHeight ; 
})
animate()

// the ball have random place in a screen 
function randomSetInrFromInterval(min , max){
    return Math.floor(Math.random() * (max - min + 1) + min )
}

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HTML

CSS

window.addEventListener("resize" , ()=>{
    canvas.width = window.innerWidth ; 
    canvas.height = window.innerHeight ; 
})
animate()

// the ball have random place in a screen 
function randomSetInrFromInterval(min , max){
    return Math.floor(Math.random() * (max - min + 1) + min )
}