<html>
<head>
<meta charset="utf-8" />
<title>Canvas Workshop</title>
<style>
* { padding: 0; margin: 0; }
canvas { background: #eee; display: block; margin: 0 auto; }
</style>
</head>
<body>
<canvas id="myCanvas" width="10000" height="10000"></canvas>
<script>
var canvas = document.getElementById("myCanvas");
var ctx = canvas.getContext("2d");
var ballRadius = 10;
var x = 600;
var y = 600;
function drawBall() {
ctx.beginPath();
ctx.moveTo(x,y+100);
ctx.lineTo(x,y+100);
ctx.lineTo(x+100,y+100);
ctx.closePath();
ctx.fill();
}
function draw() {
ctx.clearRect(0, 0, canvas.width, canvas.height);
drawBall();
}
let move = (e) => {
let rect = e.target.getBoundingClientRect() ;
x = e.clientX - rect.left;
y = e.clientY - rect.top;
draw();
}
canvas.addEventListener('load',drawBall());
canvas.addEventListener('mousedown', ()=> {
canvas.addEventListener('mousemove',move);
});
canvas.addEventListener('mouseup',()=> {
canvas.removeEventListener('mousemove',move);
});
</script>
</body>
</html>
