metanohi-misc-subsites/subsites/projects/canvas/df.htm

76 lines
1.4 KiB
HTML

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3c.org/1999/xhtml">
<head>
<title>CanvasDraw :: Paintbrush</title>
<style type='text/css'>
* {
margin:0;
padding:0;
}
canvas {
position:absolute;
top:50%;
left:50%;
margin-top:-200px;
margin-left:-320px;
border:1px solid #000;
}
</style>
<script type='text/javascript'>
function getwh() {
if (self.innerHeight) {
h=self.innerHeight
w=self.innerWidth
}
else if (document.documentElement && document.documentElement.clientHeight) {
h=document.documentElement.clientHeight
w=document.documentElement.clientHeight
}
else if (document.body) {
h=document.body.clientHeight
w=document.body.clientWidth
}
}
function ani() {
var ctx = document.getElementById('canvas').getContext('2d');
if (click) {
ctx.beginPath()
ctx.moveTo(ox,oy)
ctx.lineTo(x,y)
ctx.stroke()
}
ox=x
oy=y
setTimeout("ani()",1)
}
function load() {
x=0
y=0
ox=0
oy=0
click=false
ani()
}
function mm(e) {
getwh()
x=Math.floor(e.pageX-(w-642)/2-2)
y=Math.floor(e.pageY-(h-402)/2-2)
}
window.onload=load
document.onmousemove=mm
document.onmousedown=function(){click=true}
document.onmouseup=function(){click=false}
</script>
</head>
<body>
<canvas id='canvas' width='640' height='400'></canvas>
</body>
</html>