<SCRIPT LANGUAGE="JavaScript1.2">
function Circle (cx, cy, radius, color, dotSize, da) {
this.id = Circle.cnt++;
this.cx = cx || 100;
this.cy = cy || 100;
this.radius = radius || 100;
this.color = color || 'black';
this.dotSize = dotSize || 1;
this.da = da || Math.PI / 180;
this.left = this.cx - radius;
this.top = this.cy - radius;
this.width = 2 * this.radius + this.dotSize;
this.height = 2 * this.radius + this.dotSize;
this.relX = this.radius;
this.relY = this.radius;
if (document.layers) {
var l = this.layer = new Layer (this.width);
l.left = this.left;
l.top = this.top;
l.clip.width = this.width;
l.clip.height = this.height;
l.visibility = 'show';
}
else if (document.all || document.getElementById) {
var html = '';
html += '<DIV ID="Circle' + this.id + '"';
html += ' STYLE="position: absolute;';
html += ' left: ' + this.left + 'px; top: ' + this.top + 'px;';
html += ' width: ' + this.width + 'px; height: ' + this.height
+ 'px;';
html += '"';
html += '>';
html += '<\/DIV>';
if (document.all) {
document.body.insertAdjacentHTML('beforeEnd', html);
this.layer = document.all['Circle' + this.id];
}
else if (document.getElementById) {
var range = document.createRange();
range.setStartAfter(document.body.lastChild);
var docFrag = range.createContextualFragment(html);
document.body.appendChild(docFrag);
this.layer = document.getElementById('Circle' + this.id);
}
}
for (var a = 0; a < Math.PI * 2; a += this.da) {
var x = this.relY + this.radius * Math.sin(a);
var y = this.relY + this.radius * Math.cos(a);
if (document.layers) {
l = new Layer (this.dotSize, this.layer);
l.clip.width = this.dotSize;
l.clip.height = this.dotSize;
l.bgColor = this.color;
l.left = x;
l.top = y;
l.visibility = 'inherit';
}
else if (document.all || document.getElementById) {
var html = '';
html += '<SPAN';
html += ' STYLE="position: absolute; visibility: inherit;';
html += ' left: ' + x + 'px; top: ' + y + 'px;';
html += ' width: ' + this.dotSize + 'px; height: ' + this.dotSize
+ 'px;';
html += ' background-color: ' + this.color + ';';
html += document.all ?
'clip: rect (0 ' + this.dotSize + ' ' + this.dotSize + ' 0);' :
'';
html += '"';
html += '>';
html += '<\/SPAN>';
if (document.all) {
this.layer.insertAdjacentHTML('beforeEnd', html);
}
else if (document.getElementById) {
var range = document.createRange();
range.setStartAfter(this.layer);
var docFrag = range.createContextualFragment(html);
this.layer.appendChild(docFrag);
}
}
}
}
Circle.cnt = 0;
</SCRIPT>
<SCRIPT>
var circle1, circle2;
function init () {
var cx = window.innerWidth ?
parseInt(window.innerWidth / 2) :
parseInt(document.body.clientWidth / 2);
var cy = window.innerHeight ?
parseInt(window.innerHeight / 2) :
parseInt(document.body.clientHeight / 2);
circle1 = new Circle (cx, cy, 100, 'lime');
circle2 = new Circle (cx, cy, 150, 'orange', 2);
}
</SCRIPT>
<BODY ONLOAD="init();">![[thumbsup2]](/data/assets/smilies/thumbsup2.gif "[thumbsup2] [thumbsup2]")
![[atom]](/data/assets/smilies/atom.gif "[atom] [atom]")
---------------------------------------
![[2thumbsup]](/data/assets/smilies/2thumbsup.gif "[2thumbsup] [2thumbsup]")
---------------------------------------
<style>
I {position:absolute; width:1; height:1; clip:rect(0 1 1 0); background-color:red}
#circle {position:absolute; clip:rect(0 630 400 0)}
</style>
<script>
D = document;
IE = D.all;
function plotCircle(radius,layer) {
plot = '';
pi = Math.PI;
x = -pi;
while (x<pi+.000078125) {
y = Math.sqrt((radius*radius-x*x));
if (!isNaN(y)) {
if (IE) plot += '<i style=left:' + Math.round(x*50+314) + ';top:' + Math.round(y*50+200) + '></i>';
else D[layer].document.write('<layer left=' + Math.round(x*50+314) + ' top=' + Math.round(y*50+194) + '><font size=1 color=red>·</layer>');
}
if (x>-pi+.78 && x<pi-.78) x += .02;
else if (x>-pi+.26 && x<pi-.26) x += .01;
else if (x>-pi+.06 && x<pi-.08) x += .005;
else if (x>-pi+.003 && x<pi-.004) x += .00125;
else x += .000078125;
}
x = pi;
while (x>-pi-.000078125) {
y = -Math.sqrt((radius*radius-x*x));
if (!isNaN(y)) {
if (IE) plot += '<i style=left:' + Math.round(x*50+314) + ';top:' + Math.round(y*50+200) + '></i>';
else D[layer].document.write('<layer left=' + Math.round(x*50+314) + ' top=' + Math.round(y*50+194) + '><font size=1 color=red>·</layer>');
}
if (x<pi-.78 && x>-pi+.78) x -= .02;
else if (x<pi-.26 && x>-pi+.26) x -= .01;
else if (x<pi-.06 && x>-pi+.08) x -= .005;
else if (x<pi-.003 && x>-pi+.004) x -= .00125;
else x -= .000078125;
}
if (IE) IE[layer].innerHTML = plot;
}
</script>
<div id=circle></div>
<TABLE width=630 height=400 bgcolor=black><tr><td><br></td></tr></TABLE>
<FORM>
<input type=button value=Draw! onClick=plotCircle(Math.PI,'circle')><br><br>
</FORM>
.
