85 lines
2.3 KiB
HTML
85 lines
2.3 KiB
HTML
<!DOCTYPE html>
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<html>
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<!-- ahhh -->
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<body style="margin:0;overflow: hidden;">
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<canvas id="myCanvas" width="10" height="10" style="display: block;box-sizing: border-box;">
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Your browser does not support the HTML5 canvas tag.</canvas>
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<script>
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let c = document.getElementById("myCanvas");
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let 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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let deg_per_sec = 30;
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let time = 120;
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let fps = 60;
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centerX = ctx.canvas.width / 2;
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centerY = ctx.canvas.height / 2;
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rotation = 0; //was = j = angle
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currentFrame = 0; //was = i
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function render() {
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if (currentFrame < time / (1 / fps)) {
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setTimeout(() => {
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render();
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render_clear();
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Draw_Spiral_Pattern(3, 200, rotation, centerX, centerY, 'red')
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}, 1000 / fps);
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rotation += deg_per_sec / fps; // was = j = angle, now = rotation
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currentFrame += 1; // was = i
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}
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}
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render();
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function Draw_Spiral_Pattern(sides, radius, rotation, x, y, colour) {
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var rot = Math.round((sides - 2) * 180 / sides * 2)
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var piv = 360 / sides;
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var stt = 0.5 * Math.PI - rad(rot) //+ rad(rotation);
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var end = 0;
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var n = radius / ((radius / 10) * (radius / 10)) //pixel correction for mid leaf
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for (let i = 1; i < sides + 1; i++) {
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end = stt + rad(rot);
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ctx.beginPath();
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ctx.arc(x + Math.cos(rad(90 + piv * i + rotation)) * radius, y + Math.sin(rad(90 + piv * i + rotation)) * radius, radius, stt + rad(rotation) - (stt - end) / 2, end + rad(rotation) + rad(n), 0);
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ctx.strokeStyle = colour;
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ctx.stroke();
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ctx.beginPath();
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ctx.arc(x + Math.cos(rad(90 + piv * i - rotation)) * radius, y + Math.sin(rad(90 + piv * i - rotation)) * radius, radius, stt - rad(rotation), end - (end - stt) / 2 + rad(n) - rad(rotation), 0);
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ctx.strokeStyle = colour;
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ctx.stroke();
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stt = end + -(rad(rot - piv)) //+rad(30);
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}
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}
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function rad(degrees) {
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var pi = Math.PI;
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return degrees * (pi / 180);
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}
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function render_clear() {
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ctx.clearRect(0, 0, ctx.canvas.width, ctx.canvas.height);
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ctx.fillStyle = "black";
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ctx.fillRect(0, 0, ctx.canvas.width, ctx.canvas.height);
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}
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</script>
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</body>
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</html> |