site-z/canvas.html at master · LFF5644/site-z · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<meta name="viewport" content="width=device-width, initial-scale=1.0">
	<title>Canvas</title>
</head>
<body>
	<h1>Canvas</h1>
	<canvas id="canvas_main" width="200" height="100" style="border:1px solid black;"></canvas>
	<script>

		function writePixel(x,y){
			canvasContent.strokeRect(x,y,1,1);
		}
		function getRandomPos(width,height){
			return [
				Math.max(width,Math.round(Math.random()*width)),
				Math.max(height,Math.round(Math.random()*height)),
			];
		}

		const canvas=document.getElementById("canvas_main");
		const canvasContent=canvas.getContext("2d");
		canvasContent.moveTo(0,0);
		canvasContent.lineTo(200,100);
		canvasContent.stroke();

		setInterval(()=>{
			//return;
			const [x,y]=getRandomPos(200,100);
			writePixel(x,y);
			canvasContent.stroke();
		},1e3);

	</script>
</body>
</html>