169 lines
6.1 KiB
HTML
169 lines
6.1 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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Problem 4-11
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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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.dropbtn {
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background-color: #04AA6D;
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color: white;
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padding: 16px;
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font-size: 16px;
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border: none;
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}
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.dropdown {
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position: absolute;
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display: inline-block;
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}
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.dropdown-content {
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display: none;
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position: relative;
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background-color: #f1f1f1;
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box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
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z-index: 1;
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}
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.dropdown-content button {
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color: black;
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padding: 12px 16px;
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width: 100px;
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text-decoration: none;
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display: block;
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}
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.dropdown-content a:hover {background-color: #ddd;}
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.dropdown:hover .dropdown-content {display: block;}
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.dropdown:hover .dropbtn {background-color: #3e8e41;}
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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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<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 w = 1;
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var wd = 1;
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var fd = 20;
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var m = 1;
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var t = 0;
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var dt = 0.1;
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var xPos = 0;
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var yPos = 0;
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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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t += dt;
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setTimeout(Update, 1000/60)
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}
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function Draw()
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{
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ctx.beginPath();
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ctx.arc(xPos, yPos, 100, 0, Math.PI * 2);
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ctx.stroke();
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var x1 = -fd * (2 * w * w - wd * wd) * Math.cos(wd * t) /
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(wd * wd * (4 * w * w - wd * wd) * m);
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var y1 = Math.sqrt(10000 - x1 * x1);
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var t1 = Math.atan(y1 / x1);
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var x2 = -fd * 2 * Math.cos(wd * t) /
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(wd * wd * (4 * w * w - wd * wd) * m);
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var y2 = -Math.sqrt(10000 - x2 * x2);
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var t2 = Math.atan(y2 / x2);
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if (x1 < 0 || y1 < 0)
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{
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t1 += Math.PI;
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}
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if (x2 < 0)
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{
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t2 -= Math.PI;
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}
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ctx.beginPath();
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ctx.arc(xPos + x1, yPos + y1, 10, 0, Math.PI * 2);
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ctx.fill();
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ctx.beginPath();
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ctx.arc(xPos + x2, yPos + y2, 10, 0, Math.PI * 2);
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ctx.fill();
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drawSpring(1, 3, Math.abs(t2 - t1), -10, 20, Math.min(t1, t2) - Math.PI / 2 + 0.2, 105, 0.1, xPos, yPos);
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drawSpring(1, 3, Math.PI * 2 - Math.abs(t2 - t1) -0.1, -10, 20, Math.max(t1, t2) - Math.PI / 2 + 0.2, 105, 0.1, xPos, yPos);
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}
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function drawSpring(a, b, tSize, rSize, numLoops, t, r, pStep, x, y)
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{
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var pStart = Math.PI / 2;
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var pEnd = (3 * Math.PI / 2) + (2 * Math.PI * numLoops);
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var tEnd = a * pEnd - b * Math.sin(pEnd);
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var rEnd = a + b;
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var tFactor = tSize / tEnd;
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var rFactor = rSize / rEnd;
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var tShift = t - a * (Math.PI / 2) + b * Math.sin(Math.PI / 2);
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var rShift = r - a + b * Math.cos(Math.PI / 2);
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for (p = pStart; p <= pEnd; p += pStep)
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{
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var theta = tShift + tFactor * (a * p - b * Math.sin(p));
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var radius = rShift + rFactor * (a - b * Math.cos(p));
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ctx.beginPath();
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ctx.moveTo(x + radius * Math.cos(theta), y + radius * Math.sin(theta));
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theta = tShift + tFactor * (a * (p + pStep) - b * Math.sin((p + pStep)));
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radius = rShift + rFactor * (a - b * Math.cos(p + pStep));
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ctx.lineTo(x + radius * Math.cos(theta), y + radius * Math.sin(theta));
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ctx.stroke();
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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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Update();
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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> |