132 lines
4.2 KiB
HTML
132 lines
4.2 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 3-11
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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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</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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c.width = window.innerWidth;
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c.height = window.innerHeight;
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//Time step
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var dt = 0.002;
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var t = 0;
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var g = 980;
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var y = 10;
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var yp = 0;
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var l = 200;
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var fallT = 0;
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var a = Math.sqrt(g / l);
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//Relative position of canvas
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var xPos = 0;
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var yPos = 200;
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//Moves and scales canvas
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ctx.translate(ctx.canvas.width / 2, ctx.canvas.height / 2)
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ctx.scale(1, -1);
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function Reset()
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{
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t = 0;
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fallT = 0;
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y = 10;
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}
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Reset();
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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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if (t > 2.5)
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{
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Reset();
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}
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if (y <= l)
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{
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y = 10 * Math.cosh(a * t);
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} else
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{
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if (fallT == 0)
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{
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fallT = t;
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}
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y += (a * Math.sqrt(l ** 2 + 100) + g * (t- fallT)) * dt;
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}
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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.strokeStyle = "#ee0000";
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ctx.lineWidth = 2;
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if (y <= l)
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{
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ctx.beginPath();
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ctx.moveTo(xPos, yPos);
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ctx.lineTo(xPos, yPos - y);
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ctx.stroke();
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ctx.beginPath();
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ctx.moveTo(xPos, yPos);
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ctx.lineTo(xPos + (l - y), yPos);
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ctx.stroke();
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} else
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{
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ctx.beginPath();
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ctx.moveTo(xPos, yPos - y);
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ctx.lineTo(xPos, yPos - y + l);
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ctx.stroke();
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}
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ctx.lineWidth = 1;
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ctx.strokeStyle = "#000000";
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ctx.beginPath();
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ctx.moveTo(xPos + 2, -c.height);
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ctx.lineTo(xPos + 2, yPos - 2);
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ctx.lineTo(c.width, yPos - 2);
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ctx.stroke();
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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, -1);
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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> |