Рисуем... с тормозами
<html>
<head>
<style>
.dot {position: absolute; left: -1; top: -1; width: 1; height: 1;}
</style>
<script>
var nn6 = (navigator.userAgent.indexOf('Netscape6')!=-1);
var nn = (!nn6 && navigator.appName=='Netscape');
var ie = (navigator.appName=='Microsoft Internet Explorer');
var dotcount = 0;
function dot(x,y,color) {
document.write('<div name="dt'+dotcount+'" id="dt'+dotcount+'" class="dot"><table border="0" cellspacing="0" cellpadding="0" width="100%" height="100%"><tr><td bgcolor="'+color+'"><img src="i.gif" width="1" height="1"></td></tr></table></div>');
if (ie) {
document.all['dt'+dotcount].style.pixelLeft = x;
document.all['dt'+dotcount].style.pixelTop = y;
} else if (nn) {
document.layers['dt'+dotcount].left = x;
document.layers['dt'+dotcount].top = y;
} else if (nn6) {
document.getElementById('dt'+dotcount).style.left = x;
document.getElementById('dt'+dotcount).style.top = y;
}
dotcount++;
}
function line(x1,y1,x2,y2,color) {
dot(x1,y1,color);
var r = Math.sqrt((x2-x1)*(x2-x1)+(y2-y1)*(y2-y1));
var sx = (x2-x1)/r;
var sy = (y2-y1)/r;
for (var i=1; i<r; i++) {
var x = x1 + i*sx;
var y = y1 + i*sy;
dot(x,y,color);
}
dot(x2,y2,color);
}
</script>
</head>
<body>
<script>
line(10,10,100,15,'#FF0000');
line(100,15,100,150,'#00FF00');
line(100,150,10,10,'#0000FF');
</script>
</body>
</html>