48 lines
976 B
JavaScript
48 lines
976 B
JavaScript
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// slider UI objects
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mx = ui.slider(0,2000).initial(1028)
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my = ui.slider(0,2000).initial(1409)
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ms = ui.slider(0,2000).initial(615)
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// compute slider-derived values
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xofs = (mx.value-1000)/500
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yofs = (my.value-1000)/500
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zoom = Math.pow(0.99, ms.value)
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// create bitmap
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fract = bitmap.indexed(512,256,8)
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// compute fractal using assign()
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fract.assign(mandel)
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// mandelbrot pixel function
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function mandel(x,y) {
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return iterateEquation(
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(x-fract.width/2)*zoom-xofs,
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(y-fract.height/2)*zoom-yofs, 10, 256)[0];
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}
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// mandelbrot compute function
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function iterateEquation(Cr, Ci, escapeRadius, iterations)
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{
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var Zr = 0;
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var Zi = 0;
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var Tr = 0;
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var Ti = 0;
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var n = 0;
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for ( ; n<iterations && (Tr+Ti)<=escapeRadius; ++n ) {
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Zi = 2 * Zr * Zi + Ci;
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Zr = Tr - Ti + Cr;
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Tr = Zr * Zr;
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Ti = Zi * Zi;
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}
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for ( var e=0; e<4; ++e ) {
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Zi = 2 * Zr * Zi + Ci;
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Zr = Tr - Ti + Cr;
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Tr = Zr * Zr;
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Ti = Zi * Zi;
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}
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return [n, Tr, Ti];
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}
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