263 lines
8.7 KiB
HTML
263 lines
8.7 KiB
HTML
<!--
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This work is licensed under CC BY-NC-ND 4.0
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Link to license: http://creativecommons.org/licenses/by-nc-nd/4.0/
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Attribute to Russell Georgi
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-->
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<html>
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<head>
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<title>
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Waves: Purcell
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</title>
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<style>
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html, body {
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width: 100%;
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height: 100%;
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margin: 0px;
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border: 0;
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overflow: hidden;
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display: block;
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}
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canvas {
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position: absolute;
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}
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.slideContainer {
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position: relative;
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}
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#countdown {
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position: absolute;
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top: 50%;
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left: 50%;
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font-size: 150px;
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text-align: center;
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vertical-align: middle;
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transform: translate(-50%, -50%);
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}
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</style>
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</head>
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<body>
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<canvas id="myCanvas" width="1" height="1" style="border:1px solid #ffffff;">
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Your browser does not support the HTML5 canvas tag.</canvas>
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<t id="countdown"></t>
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<div class="slidecontainer">
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<t>X</t>
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<input type="range" min="0" max="0.95" value="0.4" step = ".05" id="xSlider">
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<br>
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<t>Number of rays</t>
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<input type="range" min="10" max="50" value="20" step = "1" id="nSlider">
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<br>
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<t id="countdown"></t>
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</div>
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<script>
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var c = document.getElementById("myCanvas");
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var ctx = c.getContext("2d");
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ctx.canvas.width = window.innerWidth;
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ctx.canvas.height = window.innerHeight;
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var v = 0.4;
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var gaminv = Math.sqrt(1 - v ** 2);
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var rmax = 500;
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var n = 40;
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var scrwidth = c.width / 3;
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var dr = 1.5;
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var mm = 400 / dr;
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var dth = .01;
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var tg = 0;
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var theta = 0;
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var mInit = -120;
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var m = -100;
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var xPos = 0;
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var yPos = 0;
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var xSlider = document.getElementById("xSlider");
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xSlider.oninput = function()
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{
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v = parseFloat(this.value);
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gaminv = Math.sqrt(1 - v ** 2);
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rmax = 500;
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m = mInit;
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}
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nSlider.oninput = function()
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{
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n = parseFloat(this.value);
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}
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function fnatn(s, c)
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{
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if (c > 0)
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{
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return Math.atan(s / c);
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}
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if (c == 0)
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{
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return Math.PI / 2;
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}
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if (c < 0)
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{
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return Math.PI - Math.atan(-s / c);
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}
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}
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ctx.translate(ctx.canvas.width / 2, ctx.canvas.height / 2);
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ctx.scale(1.5, -1.5);
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function Clear(ctx)
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{
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ctx.clearRect(-c.width, -c.height, c.width * 2, c.height * 2);
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}
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function Update()
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{
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Clear(ctx);
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Draw();
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m += 1;
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if (m < 0)
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{
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document.getElementById("countdown").textContent = (Math.ceil((-m) / 60)).toString();
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}
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if (m == 0)
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{
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document.getElementById("countdown").textContent = "";
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}
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setTimeout(Update, 1000/60);
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}
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Update();
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function Draw()
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{
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r = 0;
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tt = 5;
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if (m > 0)
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{
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r = m;
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}
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rp = r + tt;
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if (m < -tt)
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{
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rp = 0;
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}
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if (rp > rmax)
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{
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m = mInit;
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}
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ctx.beginPath();
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ctx.moveTo(v * r, 0);
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ctx.lineTo(rmax, 0);
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ctx.stroke();
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if ((n / 2) - Math.floor(n / 2) == 0)
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{
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ctx.beginPath();
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ctx.moveTo(v * r, 0);
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ctx.lineTo(-rmax, 0);
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ctx.stroke();
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}
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for (j = 1; j <= (n - 1) / 2; j++)
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{
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theta = 2 * Math.PI * j / n;
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cost = Math.cos(theta)
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sint = Math.sin(theta)
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costp = (cost + v) / (1 + v * cost)
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sintp = gaminv * sint / (1 + v * cost)
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thetap = fnatn(sintp, costp)
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ctx.strokeStyle = Colorify((j % 5) + 3);
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ctx.beginPath();
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ctx.moveTo(xPos + rp * cost, yPos + rp * sint);
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ctx.lineTo(xPos + rmax * cost, yPos + rmax * sint);
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ctx.stroke();
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ctx.beginPath();
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ctx.moveTo(xPos + v * r, yPos);
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ctx.lineTo(xPos + r * costp, yPos + r * sintp);
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ctx.stroke();
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ctx.beginPath();
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ctx.moveTo(xPos + rp * cost, yPos - rp * sint);
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ctx.lineTo(xPos + rmax * cost, yPos - rmax * sint);
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ctx.stroke();
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ctx.beginPath();
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ctx.moveTo(xPos + v * r, yPos);
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ctx.lineTo(xPos + r * costp, yPos - r * sintp);
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ctx.stroke();
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if (Math.abs(theta - thetap) > 0.001)
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{
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console.log(thetap);
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console.log(theta);
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for (thj = thetap; thj <= theta; thj += dth)
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{
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rr1 = r + tt * (thj - thetap) / (theta - thetap);
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rr2 = rr1 + tt * dth / (theta - thetap);
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ctx.beginPath();
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ctx.moveTo(xPos + rr1 * Math.cos(thj), yPos + rr1 * Math.sin(thj));
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ctx.lineTo(xPos + rr2 * Math.cos(thj + dth), yPos + rr2 * Math.sin(thj + dth));
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ctx.stroke();
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ctx.beginPath();
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ctx.moveTo(xPos + rr1 * Math.cos(thj), yPos - rr1 * Math.sin(thj));
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ctx.lineTo(xPos + rr2 * Math.cos(thj + dth), yPos - rr2 * Math.sin(thj + dth));
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ctx.stroke();
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rr1 = rr2;
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}
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} else
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{
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console.log("No");
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ctx.beginPath();
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ctx.moveTo(xPos + r * Math.cos(theta), yPos + r * Math.sin(theta));
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ctx.lineTo(xPos + rp * Math.cos(theta), yPos + rp * Math.sin(theta));
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ctx.stroke();
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ctx.beginPath();
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ctx.moveTo(xPos + r * Math.cos(theta), yPos - r * Math.sin(theta));
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ctx.lineTo(xPos + rp * Math.cos(theta), yPos - rp * Math.sin(theta));
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ctx.stroke();
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}
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}
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}
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window.addEventListener('resize', function(event) {
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c.width = window.innerWidth;
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c.height = window.innerHeight;
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ctx.translate(c.width / 2, c.height / 2);
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ctx.scale(1.5, -1.5);
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}, true);
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function Colorify(n)
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{
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if (n == 0)
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{
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return "#000000"
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} else if (n == 1)
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{
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return "#0000aa"
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} else if (n == 2)
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{
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return "#00aa00"
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} else if (n == 3)
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{
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return "#00aaaa"
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} else if (n == 4)
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{
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return "#aa0000"
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} else if (n == 5)
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{
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return "#aa00aa"
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} else if (n == 6)
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{
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return "#aa5500"
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} else if (n == 7)
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{
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return "#aaaaaa"
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}
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}
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function sleep(ms) {
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return new Promise(resolve => setTimeout(resolve, ms));
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}
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</script>
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</body>
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<p xmlns:cc="http://creativecommons.org/ns#" style="font-size: 1vw; bottom: 0px; position: absolute;">
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This work is licensed under
|
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<a href="http://creativecommons.org/licenses/by-nc-nd/4.0/?ref=chooser-v1" target="_blank" rel="license noopener noreferrer" style="display:inline-block;">CC BY-NC-ND 4.0<img style="height:22px!important;margin-left:3px;vertical-align:text-bottom;" src="https://mirrors.creativecommons.org/presskit/icons/cc.svg?ref=chooser-v1"><img style="height:22px!important;margin-left:3px;vertical-align:text-bottom;" src="https://mirrors.creativecommons.org/presskit/icons/by.svg?ref=chooser-v1"><img style="height:22px!important;margin-left:3px;vertical-align:text-bottom;" src="https://mirrors.creativecommons.org/presskit/icons/nc.svg?ref=chooser-v1"><img style="height:22px!important;margin-left:3px;vertical-align:text-bottom;" src="https://mirrors.creativecommons.org/presskit/icons/nd.svg?ref=chooser-v1"></a></p>
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</html> |