<!DOCTYPE html>਍ഀ
<html lang="ja">਍ഀ
<head>਍ഀ
<meta charset="utf-8">਍ഀ
<title>わからん</title>਍ഀ
<style>਍ഀ
canvas{਍ഀ
	border: 1px solid black;਍ഀ
}਍ഀ
</style>਍ഀ
<script>਍ഀ
var x1 = Math.floor(Math.random() * 640 );਍ഀ
var y1 = Math.floor(Math.random() * 480 );਍ഀ
var x2 = Math.floor(Math.random() * 640 );਍ഀ
var y2 = Math.floor(Math.random() * 480 );਍ഀ
var vx1 = 8;਍ഀ
var vy1 = 8;਍ഀ
var vx2 = 8;਍ഀ
var vy2 = 8;਍ഀ
function drawScreen(){਍ഀ
	var canvas = document.getElementById( "myCanvas" );਍ഀ
	var myContext = canvas.getContext( "2d" );਍ഀ
਍ഀ
        if( x1 + vx1 < 0 || 640 < x1 + vx1 ){਍ഀ
                vx1 = -vx1;਍ഀ
        }਍ഀ
        ਍ഀ
        if( y1 + vy1 < 0 || 480 < y1 + vy1 ){਍ഀ
                vy1 = -vy1;਍ഀ
        }਍ഀ
        if( x2 + vx2 < 0 || 640 < x2 + vx2 ){਍ഀ
                vx2 = -vx2;਍ഀ
        }਍ഀ
        ਍ഀ
        if( y2 + vy2 < 0 || 480 < y2 + vy2 ){਍ഀ
                vy2 = -vy2;਍ഀ
        }਍ഀ
਍ഀ
        ਍ഀ
਍ഀ
        x1 += vx1;਍ഀ
        y1 += vy1;਍ഀ
        x2 += vx2;਍ഀ
        y2 += vy2;਍ഀ
਍ഀ
        myContext.clearRect( 0,0,640,480);਍ഀ
਍ഀ
        myContext.strokeStyle = "rgba( 10,97,210,0.3)";਍ഀ
        myContext.lineWidth = 10਍ഀ
        myContext.beginPath();਍ഀ
        myContext.moveTo(x1,y1);਍ഀ
        myContext.lineTo(x2,y2)਍ഀ
        myContext.stroke();਍ഀ
਍ഀ
਍ഀ
਍ഀ
਍ഀ
        setTimeout('drawScreen()',33);਍ഀ
਍ഀ
਍ഀ
}਍ഀ
</script>਍ഀ
<body onload="drawScreen();">਍ഀ
<canvas id="myCanvas" width="640" height="480">਍ഀ
このブラウザは canvas 要素に対応していません。਍ഀ
</canvas>਍ഀ
</body>਍ഀ
</html>਍ഀ