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1 (function() { |
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2 var _symbol = d3.svg.symbol(), |
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3 _line = d3.svg.line(); |
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4 |
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5 superformula = function() { |
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6 var type = _symbol.type(), |
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7 size = _symbol.size(), |
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8 segments = size, |
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9 params = {}; |
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10 |
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11 function superformula(d, i) { |
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12 var n, p = _superformulaTypes[type.call(this, d, i)]; |
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13 for (n in params) p[n] = params[n].call(this, d, i); |
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14 return _superformulaPath(p, segments.call(this, d, i), Math.sqrt(size.call(this, d, i))); |
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15 } |
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16 |
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17 superformula.type = function(x) { |
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18 if (!arguments.length) return type; |
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19 type = d3.functor(x); |
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20 return superformula; |
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21 }; |
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22 |
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23 superformula.param = function(name, value) { |
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24 if (arguments.length < 2) return params[name]; |
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25 params[name] = d3.functor(value); |
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26 return superformula; |
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27 }; |
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28 |
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29 // size of superformula in square pixels |
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30 superformula.size = function(x) { |
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31 if (!arguments.length) return size; |
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32 size = d3.functor(x); |
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33 return superformula; |
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34 }; |
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35 |
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36 // number of discrete line segments |
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37 superformula.segments = function(x) { |
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38 if (!arguments.length) return segments; |
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39 segments = d3.functor(x); |
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40 return superformula; |
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41 }; |
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42 |
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43 return superformula; |
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44 }; |
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45 |
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46 function _superformulaPath(params, n, diameter) { |
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47 var i = -1, |
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48 dt = 2 * Math.PI / n, |
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49 t, |
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50 r = 0, |
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51 x, |
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52 y, |
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53 points = []; |
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54 |
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55 while (++i < n) { |
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56 t = params.m * (i * dt - Math.PI) / 4; |
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57 t = Math.pow(Math.abs(Math.pow(Math.abs(Math.cos(t) / params.a), params.n2) |
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58 + Math.pow(Math.abs(Math.sin(t) / params.b), params.n3)), -1 / params.n1); |
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59 if (t > r) r = t; |
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60 points.push(t); |
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61 } |
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62 |
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63 r = diameter * Math.SQRT1_2 / r; |
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64 i = -1; while (++i < n) { |
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65 x = (t = points[i] * r) * Math.cos(i * dt); |
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66 y = t * Math.sin(i * dt); |
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67 points[i] = [Math.abs(x) < 1e-6 ? 0 : x, Math.abs(y) < 1e-6 ? 0 : y]; |
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68 } |
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69 |
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70 return _line(points) + "Z"; |
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71 } |
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72 |
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73 var _superformulaTypes = { |
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74 asterisk: {m: 12, n1: .3, n2: 0, n3: 10, a: 1, b: 1}, |
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75 bean: {m: 2, n1: 1, n2: 4, n3: 8, a: 1, b: 1}, |
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76 butterfly: {m: 3, n1: 1, n2: 6, n3: 2, a: .6, b: 1}, |
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77 circle: {m: 4, n1: 2, n2: 2, n3: 2, a: 1, b: 1}, |
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78 clover: {m: 6, n1: .3, n2: 0, n3: 10, a: 1, b: 1}, |
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79 cloverFour: {m: 8, n1: 10, n2: -1, n3: -8, a: 1, b: 1}, |
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80 cross: {m: 8, n1: 1.3, n2: .01, n3: 8, a: 1, b: 1}, |
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81 diamond: {m: 4, n1: 1, n2: 1, n3: 1, a: 1, b: 1}, |
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82 drop: {m: 1, n1: .5, n2: .5, n3: .5, a: 1, b: 1}, |
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83 ellipse: {m: 4, n1: 2, n2: 2, n3: 2, a: 9, b: 6}, |
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84 gear: {m: 19, n1: 100, n2: 50, n3: 50, a: 1, b: 1}, |
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85 heart: {m: 1, n1: .8, n2: 1, n3: -8, a: 1, b: .18}, |
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86 heptagon: {m: 7, n1: 1000, n2: 400, n3: 400, a: 1, b: 1}, |
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87 hexagon: {m: 6, n1: 1000, n2: 400, n3: 400, a: 1, b: 1}, |
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88 malteseCross: {m: 8, n1: .9, n2: .1, n3: 100, a: 1, b: 1}, |
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89 pentagon: {m: 5, n1: 1000, n2: 600, n3: 600, a: 1, b: 1}, |
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90 rectangle: {m: 4, n1: 100, n2: 100, n3: 100, a: 2, b: 1}, |
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91 roundedStar: {m: 5, n1: 2, n2: 7, n3: 7, a: 1, b: 1}, |
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92 square: {m: 4, n1: 100, n2: 100, n3: 100, a: 1, b: 1}, |
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93 star: {m: 5, n1: 30, n2: 100, n3: 100, a: 1, b: 1}, |
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94 triangle: {m: 3, n1: 100, n2: 200, n3: 200, a: 1, b: 1} |
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95 }; |
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96 |
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97 superformulaTypes = d3.keys(_superformulaTypes); |
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98 })(); |