Setting backgroundImage in a simple JavaScript video game

https://stackoverflow.com/questions/63202599/setting-backgroundimage-in-a-simple-javascript-video-game/63202710

by Ihor Vyspiansky

HTML

<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0"/>
</head>
<body onload="startGame()">
<p>Make sure this window has focus, then you can use the arrow keys on you keyboard to move the red square.</p>
</body>
</html>

CSS

/*body {
  background-image: url(https://images.unsplash.com/photo-1586294180396-0d1d93e0b71a?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&auto=format&fit=crop&w=2467&q=80);
  background-repeat: no-repeat;
  background-attachment: fixed;
  background-size: cover;
}*/

canvas {
  background-image: url(https://images.unsplash.com/photo-1519435887317-eabcf2ab8075?ixlib=rb-1.2.1&auto=format&fit=crop&w=1350&q=80);
  background-repeat: no-repeat;
  background-attachment: fixed;
  background-size: cover;
  border: 1px solid #d3d3d3;
}

JavaScript

var myGamePiece;

function startGame() {
    myGameArea.start();
    myGamePiece = new component(30, 30, "red", 10, 120);
}

var myGameArea = {
    canvas : document.createElement("canvas"),
    start : function() {
        this.canvas.width = 480;
        this.canvas.height = 270;
        this.context = this.canvas.getContext("2d");
        document.body.insertBefore(this.canvas, document.body.childNodes[0]);
        this.interval = setInterval(updateGameArea, 20);
        window.addEventListener('keydown', function (e) {
            myGameArea.key = e.keyCode;
        })
        window.addEventListener('keyup', function (e) {
            myGameArea.key = false;
        })
    }, 
    clear : function(){
        this.context.clearRect(0, 0, this.canvas.width, this.canvas.height);
    }
}

function component(width, height, color, x, y) {
    this.gamearea = myGameArea;
    this.width = width;
    this.height = height;
    this.speedX = 0;
    this.speedY = 0;    
    this.x = x;
    this.y = y;    
    this.update = function() {
        ctx = myGameArea.context;
        ctx.fillStyle = color;
        ctx.fillRect(this.x, this.y, this.width, this.height);
    }
    this.newPos = function() {
        this.x += this.speedX;
        this.y += this.speedY;        
    }
}

function updateGameArea() {
    myGameArea.clear();
    myGamePiece.speedX = 0;
    myGamePiece.speedY = 0;    
    if (myGameArea.key && myGameArea.key == 37) {myGamePiece.speedX = -1; }
    if (myGameArea.key && myGameArea.key == 39) {myGamePiece.speedX = 1; }
    if (myGameArea.key && myGameArea.key == 38) {myGamePiece.speedY = -1; }
    if (myGameArea.key && myGameArea.key == 40) {myGamePiece.speedY = 1; }
    myGamePiece.newPos();    
    myGamePiece.update();
}


var canvas = document.getElementById("canvas"),
    ctx = canvas.getContext("2d");

canvas.width = 903;
canvas.height = 657;