DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>НС</title>
<script src="http://brain.js/browser.min.js"></script>
<!--<script src=”https://raw.githubusercontent.com/harthur-org/brain.js/master/browser.js"></script>-->
<style>
body {
background-color: #333;
}
#canv {
position: absolute;
top: 0;right: 0;bottom: 0;left: 0;
margin: auto;
background-color: white;
}
</style>
</head>
<body>
<canvas id="canv" style="display: block;">Ваш браузер устарел, обновитесь.</canvas>
<script>
function DCanvas(el)
{
const ctx = el.getContext('2d');
const pixel = 20;
let is_mouse_down = false;
canv.width = 500;
canv.height = 500;
this.drawLine = function(x1, y1, x2, y2, color = 'gray') {
ctx.beginPath();
ctx.strokeStyle = color;
ctx.lineJoin = 'miter';
ctx.lineWidth = 1;
ctx.moveTo(x1, y1);
ctx.lineTo(x2, y2);
ctx.stroke();
}