161 lines
5.3 KiB
HTML
161 lines
5.3 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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Exercise 3-27
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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 = 98;
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var m1 = 1;
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var m2 = 2;
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var y1 = 0;
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var y2 = 0;
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var v1 = 0;
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var v2 = 0;
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var a1 = 0;
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var a2 = 0;
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calcAccelerations();
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//Relative position of canvas
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var xPos = 0;
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var yPos = 90;
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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(1.5, -1.5);
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function calcAccelerations()
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{
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a1 = -4 * g / 9;
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a2 = g / 9;
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}
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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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v1 += a1 * dt;
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v2 += a2 * dt;
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y1 += v1 * dt;
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y2 += v2 * dt;
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if (y2 > 60)
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{
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Reset();
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}
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setTimeout(Update, 5);
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}
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function Reset()
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{
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y1 = 0;
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y2 = 0;
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v1 = 0;
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v2 = 0;
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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.moveTo(-c.width, yPos + 50);
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ctx.lineTo(c.width, yPos + 50);
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ctx.stroke();
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ctx.beginPath();
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ctx.moveTo(xPos, yPos + 50);
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ctx.lineTo(xPos, yPos);
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ctx.stroke();
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ctx.beginPath();
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ctx.arc(xPos, yPos, 20, 0, Math.PI * 2);
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ctx.stroke();
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ctx.beginPath();
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ctx.moveTo(xPos - 20, yPos);
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ctx.lineTo(xPos - 20, yPos - (100 - y1));
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ctx.stroke();
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ctx.beginPath();
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ctx.arc(xPos - 20, yPos - (100 - y1), Math.PI * Math.sqrt(m1), 0, Math.PI * 2);
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ctx.fill();
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ctx.beginPath();
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ctx.moveTo(xPos + 20, yPos);
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ctx.lineTo(xPos + 20, yPos - (100 + y1 / 4));
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ctx.stroke();
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ctx.beginPath();
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ctx.arc(xPos + 40, yPos - (100 + y1 / 4), 20, 0, Math.PI * 2);
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ctx.stroke();
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ctx.beginPath();
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ctx.moveTo(xPos + 40, yPos - (100 + y1 / 4));
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ctx.lineTo(xPos + 40, yPos - (200 - y2));
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ctx.stroke();
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ctx.beginPath();
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ctx.moveTo(xPos + 40, yPos + 50);
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ctx.lineTo(xPos + 40, yPos);
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ctx.stroke();
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ctx.beginPath();
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ctx.moveTo(xPos + 30, yPos);
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ctx.lineTo(xPos + 20, yPos - (100 + y1 / 4));
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ctx.stroke();
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ctx.beginPath();
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ctx.moveTo(xPos + 50, yPos);
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ctx.lineTo(xPos + 60, yPos - (100 + y1 / 4));
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ctx.stroke();
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ctx.beginPath();
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ctx.arc(xPos + 40, yPos, 10, 0, Math.PI * 2);
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ctx.stroke();
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ctx.beginPath();
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ctx.moveTo(xPos + 60, yPos - (100 + y1 / 4));
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ctx.lineTo(xPos + 60, yPos + 50);
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ctx.stroke();
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ctx.beginPath();
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ctx.arc(xPos + 40, yPos - (200 - y2), Math.PI * Math.sqrt(m2), 0, Math.PI * 2);
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ctx.fill();
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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> |