| 1 | (function (global, factory) {
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| 2 | typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory() :
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| 3 | typeof define === 'function' && define.amd ? define(factory) :
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| 4 | (global = typeof globalThis !== 'undefined' ? globalThis : global || self, global.Delaunator = factory());
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| 5 | })(this, (function () { 'use strict';
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| 6 |
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| 7 | const epsilon = 1.1102230246251565e-16;
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| 8 | const splitter = 134217729;
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| 9 | const resulterrbound = (3 + 8 * epsilon) * epsilon;
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| 10 |
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| 11 | // fast_expansion_sum_zeroelim routine from oritinal code
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| 12 | function sum(elen, e, flen, f, h) {
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| 13 | let Q, Qnew, hh, bvirt;
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| 14 | let enow = e[0];
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| 15 | let fnow = f[0];
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| 16 | let eindex = 0;
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| 17 | let findex = 0;
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| 18 | if ((fnow > enow) === (fnow > -enow)) {
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| 19 | Q = enow;
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| 20 | enow = e[++eindex];
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| 21 | } else {
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| 22 | Q = fnow;
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| 23 | fnow = f[++findex];
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| 24 | }
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| 25 | let hindex = 0;
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| 26 | if (eindex < elen && findex < flen) {
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| 27 | if ((fnow > enow) === (fnow > -enow)) {
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| 28 | Qnew = enow + Q;
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| 29 | hh = Q - (Qnew - enow);
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| 30 | enow = e[++eindex];
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| 31 | } else {
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| 32 | Qnew = fnow + Q;
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| 33 | hh = Q - (Qnew - fnow);
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| 34 | fnow = f[++findex];
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| 35 | }
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| 36 | Q = Qnew;
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| 37 | if (hh !== 0) {
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| 38 | h[hindex++] = hh;
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| 39 | }
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| 40 | while (eindex < elen && findex < flen) {
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| 41 | if ((fnow > enow) === (fnow > -enow)) {
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| 42 | Qnew = Q + enow;
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| 43 | bvirt = Qnew - Q;
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| 44 | hh = Q - (Qnew - bvirt) + (enow - bvirt);
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| 45 | enow = e[++eindex];
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| 46 | } else {
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| 47 | Qnew = Q + fnow;
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| 48 | bvirt = Qnew - Q;
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| 49 | hh = Q - (Qnew - bvirt) + (fnow - bvirt);
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| 50 | fnow = f[++findex];
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| 51 | }
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| 52 | Q = Qnew;
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| 53 | if (hh !== 0) {
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| 54 | h[hindex++] = hh;
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| 55 | }
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| 56 | }
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| 57 | }
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| 58 | while (eindex < elen) {
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| 59 | Qnew = Q + enow;
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| 60 | bvirt = Qnew - Q;
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| 61 | hh = Q - (Qnew - bvirt) + (enow - bvirt);
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| 62 | enow = e[++eindex];
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| 63 | Q = Qnew;
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| 64 | if (hh !== 0) {
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| 65 | h[hindex++] = hh;
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| 66 | }
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| 67 | }
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| 68 | while (findex < flen) {
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| 69 | Qnew = Q + fnow;
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| 70 | bvirt = Qnew - Q;
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| 71 | hh = Q - (Qnew - bvirt) + (fnow - bvirt);
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| 72 | fnow = f[++findex];
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| 73 | Q = Qnew;
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| 74 | if (hh !== 0) {
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| 75 | h[hindex++] = hh;
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| 76 | }
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| 77 | }
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| 78 | if (Q !== 0 || hindex === 0) {
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| 79 | h[hindex++] = Q;
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| 80 | }
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| 81 | return hindex;
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| 82 | }
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| 83 |
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| 84 | function estimate(elen, e) {
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| 85 | let Q = e[0];
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| 86 | for (let i = 1; i < elen; i++) Q += e[i];
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| 87 | return Q;
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| 88 | }
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| 89 |
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| 90 | function vec(n) {
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| 91 | return new Float64Array(n);
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| 92 | }
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| 93 |
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| 94 | const ccwerrboundA = (3 + 16 * epsilon) * epsilon;
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| 95 | const ccwerrboundB = (2 + 12 * epsilon) * epsilon;
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| 96 | const ccwerrboundC = (9 + 64 * epsilon) * epsilon * epsilon;
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| 97 |
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| 98 | const B = vec(4);
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| 99 | const C1 = vec(8);
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| 100 | const C2 = vec(12);
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| 101 | const D = vec(16);
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| 102 | const u = vec(4);
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| 103 |
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| 104 | function orient2dadapt(ax, ay, bx, by, cx, cy, detsum) {
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| 105 | let acxtail, acytail, bcxtail, bcytail;
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| 106 | let bvirt, c, ahi, alo, bhi, blo, _i, _j, _0, s1, s0, t1, t0, u3;
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| 107 |
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| 108 | const acx = ax - cx;
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| 109 | const bcx = bx - cx;
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| 110 | const acy = ay - cy;
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| 111 | const bcy = by - cy;
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| 112 |
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| 113 | s1 = acx * bcy;
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| 114 | c = splitter * acx;
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| 115 | ahi = c - (c - acx);
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| 116 | alo = acx - ahi;
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| 117 | c = splitter * bcy;
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| 118 | bhi = c - (c - bcy);
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| 119 | blo = bcy - bhi;
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| 120 | s0 = alo * blo - (s1 - ahi * bhi - alo * bhi - ahi * blo);
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| 121 | t1 = acy * bcx;
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| 122 | c = splitter * acy;
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| 123 | ahi = c - (c - acy);
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| 124 | alo = acy - ahi;
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| 125 | c = splitter * bcx;
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| 126 | bhi = c - (c - bcx);
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| 127 | blo = bcx - bhi;
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| 128 | t0 = alo * blo - (t1 - ahi * bhi - alo * bhi - ahi * blo);
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| 129 | _i = s0 - t0;
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| 130 | bvirt = s0 - _i;
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| 131 | B[0] = s0 - (_i + bvirt) + (bvirt - t0);
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| 132 | _j = s1 + _i;
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| 133 | bvirt = _j - s1;
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| 134 | _0 = s1 - (_j - bvirt) + (_i - bvirt);
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| 135 | _i = _0 - t1;
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| 136 | bvirt = _0 - _i;
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| 137 | B[1] = _0 - (_i + bvirt) + (bvirt - t1);
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| 138 | u3 = _j + _i;
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| 139 | bvirt = u3 - _j;
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| 140 | B[2] = _j - (u3 - bvirt) + (_i - bvirt);
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| 141 | B[3] = u3;
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| 142 |
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| 143 | let det = estimate(4, B);
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| 144 | let errbound = ccwerrboundB * detsum;
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| 145 | if (det >= errbound || -det >= errbound) {
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| 146 | return det;
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| 147 | }
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| 148 |
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| 149 | bvirt = ax - acx;
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| 150 | acxtail = ax - (acx + bvirt) + (bvirt - cx);
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| 151 | bvirt = bx - bcx;
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| 152 | bcxtail = bx - (bcx + bvirt) + (bvirt - cx);
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| 153 | bvirt = ay - acy;
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| 154 | acytail = ay - (acy + bvirt) + (bvirt - cy);
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| 155 | bvirt = by - bcy;
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| 156 | bcytail = by - (bcy + bvirt) + (bvirt - cy);
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| 157 |
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| 158 | if (acxtail === 0 && acytail === 0 && bcxtail === 0 && bcytail === 0) {
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| 159 | return det;
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| 160 | }
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| 161 |
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| 162 | errbound = ccwerrboundC * detsum + resulterrbound * Math.abs(det);
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| 163 | det += (acx * bcytail + bcy * acxtail) - (acy * bcxtail + bcx * acytail);
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| 164 | if (det >= errbound || -det >= errbound) return det;
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| 165 |
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| 166 | s1 = acxtail * bcy;
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| 167 | c = splitter * acxtail;
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| 168 | ahi = c - (c - acxtail);
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| 169 | alo = acxtail - ahi;
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| 170 | c = splitter * bcy;
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| 171 | bhi = c - (c - bcy);
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| 172 | blo = bcy - bhi;
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| 173 | s0 = alo * blo - (s1 - ahi * bhi - alo * bhi - ahi * blo);
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| 174 | t1 = acytail * bcx;
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| 175 | c = splitter * acytail;
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| 176 | ahi = c - (c - acytail);
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| 177 | alo = acytail - ahi;
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| 178 | c = splitter * bcx;
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| 179 | bhi = c - (c - bcx);
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| 180 | blo = bcx - bhi;
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| 181 | t0 = alo * blo - (t1 - ahi * bhi - alo * bhi - ahi * blo);
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| 182 | _i = s0 - t0;
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| 183 | bvirt = s0 - _i;
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| 184 | u[0] = s0 - (_i + bvirt) + (bvirt - t0);
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| 185 | _j = s1 + _i;
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| 186 | bvirt = _j - s1;
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| 187 | _0 = s1 - (_j - bvirt) + (_i - bvirt);
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| 188 | _i = _0 - t1;
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| 189 | bvirt = _0 - _i;
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| 190 | u[1] = _0 - (_i + bvirt) + (bvirt - t1);
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| 191 | u3 = _j + _i;
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| 192 | bvirt = u3 - _j;
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| 193 | u[2] = _j - (u3 - bvirt) + (_i - bvirt);
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| 194 | u[3] = u3;
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| 195 | const C1len = sum(4, B, 4, u, C1);
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| 196 |
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| 197 | s1 = acx * bcytail;
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| 198 | c = splitter * acx;
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| 199 | ahi = c - (c - acx);
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| 200 | alo = acx - ahi;
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| 201 | c = splitter * bcytail;
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| 202 | bhi = c - (c - bcytail);
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| 203 | blo = bcytail - bhi;
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| 204 | s0 = alo * blo - (s1 - ahi * bhi - alo * bhi - ahi * blo);
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| 205 | t1 = acy * bcxtail;
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| 206 | c = splitter * acy;
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| 207 | ahi = c - (c - acy);
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| 208 | alo = acy - ahi;
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| 209 | c = splitter * bcxtail;
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| 210 | bhi = c - (c - bcxtail);
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| 211 | blo = bcxtail - bhi;
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| 212 | t0 = alo * blo - (t1 - ahi * bhi - alo * bhi - ahi * blo);
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| 213 | _i = s0 - t0;
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| 214 | bvirt = s0 - _i;
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| 215 | u[0] = s0 - (_i + bvirt) + (bvirt - t0);
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| 216 | _j = s1 + _i;
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| 217 | bvirt = _j - s1;
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| 218 | _0 = s1 - (_j - bvirt) + (_i - bvirt);
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| 219 | _i = _0 - t1;
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| 220 | bvirt = _0 - _i;
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| 221 | u[1] = _0 - (_i + bvirt) + (bvirt - t1);
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| 222 | u3 = _j + _i;
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| 223 | bvirt = u3 - _j;
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| 224 | u[2] = _j - (u3 - bvirt) + (_i - bvirt);
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| 225 | u[3] = u3;
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| 226 | const C2len = sum(C1len, C1, 4, u, C2);
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| 227 |
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| 228 | s1 = acxtail * bcytail;
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| 229 | c = splitter * acxtail;
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| 230 | ahi = c - (c - acxtail);
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| 231 | alo = acxtail - ahi;
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| 232 | c = splitter * bcytail;
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| 233 | bhi = c - (c - bcytail);
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| 234 | blo = bcytail - bhi;
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| 235 | s0 = alo * blo - (s1 - ahi * bhi - alo * bhi - ahi * blo);
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| 236 | t1 = acytail * bcxtail;
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| 237 | c = splitter * acytail;
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| 238 | ahi = c - (c - acytail);
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| 239 | alo = acytail - ahi;
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| 240 | c = splitter * bcxtail;
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| 241 | bhi = c - (c - bcxtail);
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| 242 | blo = bcxtail - bhi;
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| 243 | t0 = alo * blo - (t1 - ahi * bhi - alo * bhi - ahi * blo);
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| 244 | _i = s0 - t0;
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| 245 | bvirt = s0 - _i;
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| 246 | u[0] = s0 - (_i + bvirt) + (bvirt - t0);
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| 247 | _j = s1 + _i;
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| 248 | bvirt = _j - s1;
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| 249 | _0 = s1 - (_j - bvirt) + (_i - bvirt);
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| 250 | _i = _0 - t1;
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| 251 | bvirt = _0 - _i;
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| 252 | u[1] = _0 - (_i + bvirt) + (bvirt - t1);
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| 253 | u3 = _j + _i;
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| 254 | bvirt = u3 - _j;
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| 255 | u[2] = _j - (u3 - bvirt) + (_i - bvirt);
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| 256 | u[3] = u3;
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| 257 | const Dlen = sum(C2len, C2, 4, u, D);
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| 258 |
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| 259 | return D[Dlen - 1];
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| 260 | }
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| 261 |
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| 262 | function orient2d(ax, ay, bx, by, cx, cy) {
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| 263 | const detleft = (ay - cy) * (bx - cx);
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| 264 | const detright = (ax - cx) * (by - cy);
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| 265 | const det = detleft - detright;
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| 266 |
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| 267 | const detsum = Math.abs(detleft + detright);
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| 268 | if (Math.abs(det) >= ccwerrboundA * detsum) return det;
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| 269 |
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| 270 | return -orient2dadapt(ax, ay, bx, by, cx, cy, detsum);
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| 271 | }
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| 272 |
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| 273 | const EPSILON = Math.pow(2, -52);
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| 274 | const EDGE_STACK = new Uint32Array(512);
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| 275 |
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| 276 | class Delaunator {
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| 277 |
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| 278 | static from(points, getX = defaultGetX, getY = defaultGetY) {
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| 279 | const n = points.length;
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| 280 | const coords = new Float64Array(n * 2);
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| 281 |
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| 282 | for (let i = 0; i < n; i++) {
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| 283 | const p = points[i];
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| 284 | coords[2 * i] = getX(p);
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| 285 | coords[2 * i + 1] = getY(p);
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| 286 | }
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| 287 |
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| 288 | return new Delaunator(coords);
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| 289 | }
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| 290 |
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| 291 | constructor(coords) {
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| 292 | const n = coords.length >> 1;
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| 293 | if (n > 0 && typeof coords[0] !== 'number') throw new Error('Expected coords to contain numbers.');
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| 294 |
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| 295 | this.coords = coords;
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| 296 |
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| 297 | // arrays that will store the triangulation graph
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| 298 | const maxTriangles = Math.max(2 * n - 5, 0);
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| 299 | this._triangles = new Uint32Array(maxTriangles * 3);
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| 300 | this._halfedges = new Int32Array(maxTriangles * 3);
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| 301 |
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| 302 | // temporary arrays for tracking the edges of the advancing convex hull
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| 303 | this._hashSize = Math.ceil(Math.sqrt(n));
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| 304 | this._hullPrev = new Uint32Array(n); // edge to prev edge
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| 305 | this._hullNext = new Uint32Array(n); // edge to next edge
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| 306 | this._hullTri = new Uint32Array(n); // edge to adjacent triangle
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| 307 | this._hullHash = new Int32Array(this._hashSize); // angular edge hash
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| 308 |
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| 309 | // temporary arrays for sorting points
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| 310 | this._ids = new Uint32Array(n);
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| 311 | this._dists = new Float64Array(n);
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| 312 |
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| 313 | this.update();
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| 314 | }
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| 315 |
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| 316 | update() {
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| 317 | const {coords, _hullPrev: hullPrev, _hullNext: hullNext, _hullTri: hullTri, _hullHash: hullHash} = this;
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| 318 | const n = coords.length >> 1;
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| 319 |
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| 320 | // populate an array of point indices; calculate input data bbox
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| 321 | let minX = Infinity;
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| 322 | let minY = Infinity;
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| 323 | let maxX = -Infinity;
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| 324 | let maxY = -Infinity;
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| 325 |
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| 326 | for (let i = 0; i < n; i++) {
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| 327 | const x = coords[2 * i];
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| 328 | const y = coords[2 * i + 1];
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| 329 | if (x < minX) minX = x;
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| 330 | if (y < minY) minY = y;
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| 331 | if (x > maxX) maxX = x;
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| 332 | if (y > maxY) maxY = y;
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| 333 | this._ids[i] = i;
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| 334 | }
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| 335 | const cx = (minX + maxX) / 2;
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| 336 | const cy = (minY + maxY) / 2;
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| 337 |
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| 338 | let i0, i1, i2;
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| 339 |
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| 340 | // pick a seed point close to the center
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| 341 | for (let i = 0, minDist = Infinity; i < n; i++) {
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| 342 | const d = dist(cx, cy, coords[2 * i], coords[2 * i + 1]);
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| 343 | if (d < minDist) {
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| 344 | i0 = i;
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| 345 | minDist = d;
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| 346 | }
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| 347 | }
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| 348 | const i0x = coords[2 * i0];
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| 349 | const i0y = coords[2 * i0 + 1];
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| 350 |
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| 351 | // find the point closest to the seed
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| 352 | for (let i = 0, minDist = Infinity; i < n; i++) {
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| 353 | if (i === i0) continue;
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| 354 | const d = dist(i0x, i0y, coords[2 * i], coords[2 * i + 1]);
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| 355 | if (d < minDist && d > 0) {
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| 356 | i1 = i;
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| 357 | minDist = d;
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| 358 | }
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| 359 | }
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| 360 | let i1x = coords[2 * i1];
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| 361 | let i1y = coords[2 * i1 + 1];
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| 362 |
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| 363 | let minRadius = Infinity;
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| 364 |
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| 365 | // find the third point which forms the smallest circumcircle with the first two
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| 366 | for (let i = 0; i < n; i++) {
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| 367 | if (i === i0 || i === i1) continue;
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| 368 | const r = circumradius(i0x, i0y, i1x, i1y, coords[2 * i], coords[2 * i + 1]);
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| 369 | if (r < minRadius) {
|
|---|
| 370 | i2 = i;
|
|---|
| 371 | minRadius = r;
|
|---|
| 372 | }
|
|---|
| 373 | }
|
|---|
| 374 | let i2x = coords[2 * i2];
|
|---|
| 375 | let i2y = coords[2 * i2 + 1];
|
|---|
| 376 |
|
|---|
| 377 | if (minRadius === Infinity) {
|
|---|
| 378 | // order collinear points by dx (or dy if all x are identical)
|
|---|
| 379 | // and return the list as a hull
|
|---|
| 380 | for (let i = 0; i < n; i++) {
|
|---|
| 381 | this._dists[i] = (coords[2 * i] - coords[0]) || (coords[2 * i + 1] - coords[1]);
|
|---|
| 382 | }
|
|---|
| 383 | quicksort(this._ids, this._dists, 0, n - 1);
|
|---|
| 384 | const hull = new Uint32Array(n);
|
|---|
| 385 | let j = 0;
|
|---|
| 386 | for (let i = 0, d0 = -Infinity; i < n; i++) {
|
|---|
| 387 | const id = this._ids[i];
|
|---|
| 388 | const d = this._dists[id];
|
|---|
| 389 | if (d > d0) {
|
|---|
| 390 | hull[j++] = id;
|
|---|
| 391 | d0 = d;
|
|---|
| 392 | }
|
|---|
| 393 | }
|
|---|
| 394 | this.hull = hull.subarray(0, j);
|
|---|
| 395 | this.triangles = new Uint32Array(0);
|
|---|
| 396 | this.halfedges = new Uint32Array(0);
|
|---|
| 397 | return;
|
|---|
| 398 | }
|
|---|
| 399 |
|
|---|
| 400 | // swap the order of the seed points for counter-clockwise orientation
|
|---|
| 401 | if (orient2d(i0x, i0y, i1x, i1y, i2x, i2y) < 0) {
|
|---|
| 402 | const i = i1;
|
|---|
| 403 | const x = i1x;
|
|---|
| 404 | const y = i1y;
|
|---|
| 405 | i1 = i2;
|
|---|
| 406 | i1x = i2x;
|
|---|
| 407 | i1y = i2y;
|
|---|
| 408 | i2 = i;
|
|---|
| 409 | i2x = x;
|
|---|
| 410 | i2y = y;
|
|---|
| 411 | }
|
|---|
| 412 |
|
|---|
| 413 | const center = circumcenter(i0x, i0y, i1x, i1y, i2x, i2y);
|
|---|
| 414 | this._cx = center.x;
|
|---|
| 415 | this._cy = center.y;
|
|---|
| 416 |
|
|---|
| 417 | for (let i = 0; i < n; i++) {
|
|---|
| 418 | this._dists[i] = dist(coords[2 * i], coords[2 * i + 1], center.x, center.y);
|
|---|
| 419 | }
|
|---|
| 420 |
|
|---|
| 421 | // sort the points by distance from the seed triangle circumcenter
|
|---|
| 422 | quicksort(this._ids, this._dists, 0, n - 1);
|
|---|
| 423 |
|
|---|
| 424 | // set up the seed triangle as the starting hull
|
|---|
| 425 | this._hullStart = i0;
|
|---|
| 426 | let hullSize = 3;
|
|---|
| 427 |
|
|---|
| 428 | hullNext[i0] = hullPrev[i2] = i1;
|
|---|
| 429 | hullNext[i1] = hullPrev[i0] = i2;
|
|---|
| 430 | hullNext[i2] = hullPrev[i1] = i0;
|
|---|
| 431 |
|
|---|
| 432 | hullTri[i0] = 0;
|
|---|
| 433 | hullTri[i1] = 1;
|
|---|
| 434 | hullTri[i2] = 2;
|
|---|
| 435 |
|
|---|
| 436 | hullHash.fill(-1);
|
|---|
| 437 | hullHash[this._hashKey(i0x, i0y)] = i0;
|
|---|
| 438 | hullHash[this._hashKey(i1x, i1y)] = i1;
|
|---|
| 439 | hullHash[this._hashKey(i2x, i2y)] = i2;
|
|---|
| 440 |
|
|---|
| 441 | this.trianglesLen = 0;
|
|---|
| 442 | this._addTriangle(i0, i1, i2, -1, -1, -1);
|
|---|
| 443 |
|
|---|
| 444 | for (let k = 0, xp, yp; k < this._ids.length; k++) {
|
|---|
| 445 | const i = this._ids[k];
|
|---|
| 446 | const x = coords[2 * i];
|
|---|
| 447 | const y = coords[2 * i + 1];
|
|---|
| 448 |
|
|---|
| 449 | // skip near-duplicate points
|
|---|
| 450 | if (k > 0 && Math.abs(x - xp) <= EPSILON && Math.abs(y - yp) <= EPSILON) continue;
|
|---|
| 451 | xp = x;
|
|---|
| 452 | yp = y;
|
|---|
| 453 |
|
|---|
| 454 | // skip seed triangle points
|
|---|
| 455 | if (i === i0 || i === i1 || i === i2) continue;
|
|---|
| 456 |
|
|---|
| 457 | // find a visible edge on the convex hull using edge hash
|
|---|
| 458 | let start = 0;
|
|---|
| 459 | for (let j = 0, key = this._hashKey(x, y); j < this._hashSize; j++) {
|
|---|
| 460 | start = hullHash[(key + j) % this._hashSize];
|
|---|
| 461 | if (start !== -1 && start !== hullNext[start]) break;
|
|---|
| 462 | }
|
|---|
| 463 |
|
|---|
| 464 | start = hullPrev[start];
|
|---|
| 465 | let e = start, q;
|
|---|
| 466 | while (q = hullNext[e], orient2d(x, y, coords[2 * e], coords[2 * e + 1], coords[2 * q], coords[2 * q + 1]) >= 0) {
|
|---|
| 467 | e = q;
|
|---|
| 468 | if (e === start) {
|
|---|
| 469 | e = -1;
|
|---|
| 470 | break;
|
|---|
| 471 | }
|
|---|
| 472 | }
|
|---|
| 473 | if (e === -1) continue; // likely a near-duplicate point; skip it
|
|---|
| 474 |
|
|---|
| 475 | // add the first triangle from the point
|
|---|
| 476 | let t = this._addTriangle(e, i, hullNext[e], -1, -1, hullTri[e]);
|
|---|
| 477 |
|
|---|
| 478 | // recursively flip triangles from the point until they satisfy the Delaunay condition
|
|---|
| 479 | hullTri[i] = this._legalize(t + 2);
|
|---|
| 480 | hullTri[e] = t; // keep track of boundary triangles on the hull
|
|---|
| 481 | hullSize++;
|
|---|
| 482 |
|
|---|
| 483 | // walk forward through the hull, adding more triangles and flipping recursively
|
|---|
| 484 | let n = hullNext[e];
|
|---|
| 485 | while (q = hullNext[n], orient2d(x, y, coords[2 * n], coords[2 * n + 1], coords[2 * q], coords[2 * q + 1]) < 0) {
|
|---|
| 486 | t = this._addTriangle(n, i, q, hullTri[i], -1, hullTri[n]);
|
|---|
| 487 | hullTri[i] = this._legalize(t + 2);
|
|---|
| 488 | hullNext[n] = n; // mark as removed
|
|---|
| 489 | hullSize--;
|
|---|
| 490 | n = q;
|
|---|
| 491 | }
|
|---|
| 492 |
|
|---|
| 493 | // walk backward from the other side, adding more triangles and flipping
|
|---|
| 494 | if (e === start) {
|
|---|
| 495 | while (q = hullPrev[e], orient2d(x, y, coords[2 * q], coords[2 * q + 1], coords[2 * e], coords[2 * e + 1]) < 0) {
|
|---|
| 496 | t = this._addTriangle(q, i, e, -1, hullTri[e], hullTri[q]);
|
|---|
| 497 | this._legalize(t + 2);
|
|---|
| 498 | hullTri[q] = t;
|
|---|
| 499 | hullNext[e] = e; // mark as removed
|
|---|
| 500 | hullSize--;
|
|---|
| 501 | e = q;
|
|---|
| 502 | }
|
|---|
| 503 | }
|
|---|
| 504 |
|
|---|
| 505 | // update the hull indices
|
|---|
| 506 | this._hullStart = hullPrev[i] = e;
|
|---|
| 507 | hullNext[e] = hullPrev[n] = i;
|
|---|
| 508 | hullNext[i] = n;
|
|---|
| 509 |
|
|---|
| 510 | // save the two new edges in the hash table
|
|---|
| 511 | hullHash[this._hashKey(x, y)] = i;
|
|---|
| 512 | hullHash[this._hashKey(coords[2 * e], coords[2 * e + 1])] = e;
|
|---|
| 513 | }
|
|---|
| 514 |
|
|---|
| 515 | this.hull = new Uint32Array(hullSize);
|
|---|
| 516 | for (let i = 0, e = this._hullStart; i < hullSize; i++) {
|
|---|
| 517 | this.hull[i] = e;
|
|---|
| 518 | e = hullNext[e];
|
|---|
| 519 | }
|
|---|
| 520 |
|
|---|
| 521 | // trim typed triangle mesh arrays
|
|---|
| 522 | this.triangles = this._triangles.subarray(0, this.trianglesLen);
|
|---|
| 523 | this.halfedges = this._halfedges.subarray(0, this.trianglesLen);
|
|---|
| 524 | }
|
|---|
| 525 |
|
|---|
| 526 | _hashKey(x, y) {
|
|---|
| 527 | return Math.floor(pseudoAngle(x - this._cx, y - this._cy) * this._hashSize) % this._hashSize;
|
|---|
| 528 | }
|
|---|
| 529 |
|
|---|
| 530 | _legalize(a) {
|
|---|
| 531 | const {_triangles: triangles, _halfedges: halfedges, coords} = this;
|
|---|
| 532 |
|
|---|
| 533 | let i = 0;
|
|---|
| 534 | let ar = 0;
|
|---|
| 535 |
|
|---|
| 536 | // recursion eliminated with a fixed-size stack
|
|---|
| 537 | while (true) {
|
|---|
| 538 | const b = halfedges[a];
|
|---|
| 539 |
|
|---|
| 540 | /* if the pair of triangles doesn't satisfy the Delaunay condition
|
|---|
| 541 | * (p1 is inside the circumcircle of [p0, pl, pr]), flip them,
|
|---|
| 542 | * then do the same check/flip recursively for the new pair of triangles
|
|---|
| 543 | *
|
|---|
| 544 | * pl pl
|
|---|
| 545 | * /||\ / \
|
|---|
| 546 | * al/ || \bl al/ \a
|
|---|
| 547 | * / || \ / \
|
|---|
| 548 | * / a||b \ flip /___ar___\
|
|---|
| 549 | * p0\ || /p1 => p0\---bl---/p1
|
|---|
| 550 | * \ || / \ /
|
|---|
| 551 | * ar\ || /br b\ /br
|
|---|
| 552 | * \||/ \ /
|
|---|
| 553 | * pr pr
|
|---|
| 554 | */
|
|---|
| 555 | const a0 = a - a % 3;
|
|---|
| 556 | ar = a0 + (a + 2) % 3;
|
|---|
| 557 |
|
|---|
| 558 | if (b === -1) { // convex hull edge
|
|---|
| 559 | if (i === 0) break;
|
|---|
| 560 | a = EDGE_STACK[--i];
|
|---|
| 561 | continue;
|
|---|
| 562 | }
|
|---|
| 563 |
|
|---|
| 564 | const b0 = b - b % 3;
|
|---|
| 565 | const al = a0 + (a + 1) % 3;
|
|---|
| 566 | const bl = b0 + (b + 2) % 3;
|
|---|
| 567 |
|
|---|
| 568 | const p0 = triangles[ar];
|
|---|
| 569 | const pr = triangles[a];
|
|---|
| 570 | const pl = triangles[al];
|
|---|
| 571 | const p1 = triangles[bl];
|
|---|
| 572 |
|
|---|
| 573 | const illegal = inCircle(
|
|---|
| 574 | coords[2 * p0], coords[2 * p0 + 1],
|
|---|
| 575 | coords[2 * pr], coords[2 * pr + 1],
|
|---|
| 576 | coords[2 * pl], coords[2 * pl + 1],
|
|---|
| 577 | coords[2 * p1], coords[2 * p1 + 1]);
|
|---|
| 578 |
|
|---|
| 579 | if (illegal) {
|
|---|
| 580 | triangles[a] = p1;
|
|---|
| 581 | triangles[b] = p0;
|
|---|
| 582 |
|
|---|
| 583 | const hbl = halfedges[bl];
|
|---|
| 584 |
|
|---|
| 585 | // edge swapped on the other side of the hull (rare); fix the halfedge reference
|
|---|
| 586 | if (hbl === -1) {
|
|---|
| 587 | let e = this._hullStart;
|
|---|
| 588 | do {
|
|---|
| 589 | if (this._hullTri[e] === bl) {
|
|---|
| 590 | this._hullTri[e] = a;
|
|---|
| 591 | break;
|
|---|
| 592 | }
|
|---|
| 593 | e = this._hullPrev[e];
|
|---|
| 594 | } while (e !== this._hullStart);
|
|---|
| 595 | }
|
|---|
| 596 | this._link(a, hbl);
|
|---|
| 597 | this._link(b, halfedges[ar]);
|
|---|
| 598 | this._link(ar, bl);
|
|---|
| 599 |
|
|---|
| 600 | const br = b0 + (b + 1) % 3;
|
|---|
| 601 |
|
|---|
| 602 | // don't worry about hitting the cap: it can only happen on extremely degenerate input
|
|---|
| 603 | if (i < EDGE_STACK.length) {
|
|---|
| 604 | EDGE_STACK[i++] = br;
|
|---|
| 605 | }
|
|---|
| 606 | } else {
|
|---|
| 607 | if (i === 0) break;
|
|---|
| 608 | a = EDGE_STACK[--i];
|
|---|
| 609 | }
|
|---|
| 610 | }
|
|---|
| 611 |
|
|---|
| 612 | return ar;
|
|---|
| 613 | }
|
|---|
| 614 |
|
|---|
| 615 | _link(a, b) {
|
|---|
| 616 | this._halfedges[a] = b;
|
|---|
| 617 | if (b !== -1) this._halfedges[b] = a;
|
|---|
| 618 | }
|
|---|
| 619 |
|
|---|
| 620 | // add a new triangle given vertex indices and adjacent half-edge ids
|
|---|
| 621 | _addTriangle(i0, i1, i2, a, b, c) {
|
|---|
| 622 | const t = this.trianglesLen;
|
|---|
| 623 |
|
|---|
| 624 | this._triangles[t] = i0;
|
|---|
| 625 | this._triangles[t + 1] = i1;
|
|---|
| 626 | this._triangles[t + 2] = i2;
|
|---|
| 627 |
|
|---|
| 628 | this._link(t, a);
|
|---|
| 629 | this._link(t + 1, b);
|
|---|
| 630 | this._link(t + 2, c);
|
|---|
| 631 |
|
|---|
| 632 | this.trianglesLen += 3;
|
|---|
| 633 |
|
|---|
| 634 | return t;
|
|---|
| 635 | }
|
|---|
| 636 | }
|
|---|
| 637 |
|
|---|
| 638 | // monotonically increases with real angle, but doesn't need expensive trigonometry
|
|---|
| 639 | function pseudoAngle(dx, dy) {
|
|---|
| 640 | const p = dx / (Math.abs(dx) + Math.abs(dy));
|
|---|
| 641 | return (dy > 0 ? 3 - p : 1 + p) / 4; // [0..1]
|
|---|
| 642 | }
|
|---|
| 643 |
|
|---|
| 644 | function dist(ax, ay, bx, by) {
|
|---|
| 645 | const dx = ax - bx;
|
|---|
| 646 | const dy = ay - by;
|
|---|
| 647 | return dx * dx + dy * dy;
|
|---|
| 648 | }
|
|---|
| 649 |
|
|---|
| 650 | function inCircle(ax, ay, bx, by, cx, cy, px, py) {
|
|---|
| 651 | const dx = ax - px;
|
|---|
| 652 | const dy = ay - py;
|
|---|
| 653 | const ex = bx - px;
|
|---|
| 654 | const ey = by - py;
|
|---|
| 655 | const fx = cx - px;
|
|---|
| 656 | const fy = cy - py;
|
|---|
| 657 |
|
|---|
| 658 | const ap = dx * dx + dy * dy;
|
|---|
| 659 | const bp = ex * ex + ey * ey;
|
|---|
| 660 | const cp = fx * fx + fy * fy;
|
|---|
| 661 |
|
|---|
| 662 | return dx * (ey * cp - bp * fy) -
|
|---|
| 663 | dy * (ex * cp - bp * fx) +
|
|---|
| 664 | ap * (ex * fy - ey * fx) < 0;
|
|---|
| 665 | }
|
|---|
| 666 |
|
|---|
| 667 | function circumradius(ax, ay, bx, by, cx, cy) {
|
|---|
| 668 | const dx = bx - ax;
|
|---|
| 669 | const dy = by - ay;
|
|---|
| 670 | const ex = cx - ax;
|
|---|
| 671 | const ey = cy - ay;
|
|---|
| 672 |
|
|---|
| 673 | const bl = dx * dx + dy * dy;
|
|---|
| 674 | const cl = ex * ex + ey * ey;
|
|---|
| 675 | const d = 0.5 / (dx * ey - dy * ex);
|
|---|
| 676 |
|
|---|
| 677 | const x = (ey * bl - dy * cl) * d;
|
|---|
| 678 | const y = (dx * cl - ex * bl) * d;
|
|---|
| 679 |
|
|---|
| 680 | return x * x + y * y;
|
|---|
| 681 | }
|
|---|
| 682 |
|
|---|
| 683 | function circumcenter(ax, ay, bx, by, cx, cy) {
|
|---|
| 684 | const dx = bx - ax;
|
|---|
| 685 | const dy = by - ay;
|
|---|
| 686 | const ex = cx - ax;
|
|---|
| 687 | const ey = cy - ay;
|
|---|
| 688 |
|
|---|
| 689 | const bl = dx * dx + dy * dy;
|
|---|
| 690 | const cl = ex * ex + ey * ey;
|
|---|
| 691 | const d = 0.5 / (dx * ey - dy * ex);
|
|---|
| 692 |
|
|---|
| 693 | const x = ax + (ey * bl - dy * cl) * d;
|
|---|
| 694 | const y = ay + (dx * cl - ex * bl) * d;
|
|---|
| 695 |
|
|---|
| 696 | return {x, y};
|
|---|
| 697 | }
|
|---|
| 698 |
|
|---|
| 699 | function quicksort(ids, dists, left, right) {
|
|---|
| 700 | if (right - left <= 20) {
|
|---|
| 701 | for (let i = left + 1; i <= right; i++) {
|
|---|
| 702 | const temp = ids[i];
|
|---|
| 703 | const tempDist = dists[temp];
|
|---|
| 704 | let j = i - 1;
|
|---|
| 705 | while (j >= left && dists[ids[j]] > tempDist) ids[j + 1] = ids[j--];
|
|---|
| 706 | ids[j + 1] = temp;
|
|---|
| 707 | }
|
|---|
| 708 | } else {
|
|---|
| 709 | const median = (left + right) >> 1;
|
|---|
| 710 | let i = left + 1;
|
|---|
| 711 | let j = right;
|
|---|
| 712 | swap(ids, median, i);
|
|---|
| 713 | if (dists[ids[left]] > dists[ids[right]]) swap(ids, left, right);
|
|---|
| 714 | if (dists[ids[i]] > dists[ids[right]]) swap(ids, i, right);
|
|---|
| 715 | if (dists[ids[left]] > dists[ids[i]]) swap(ids, left, i);
|
|---|
| 716 |
|
|---|
| 717 | const temp = ids[i];
|
|---|
| 718 | const tempDist = dists[temp];
|
|---|
| 719 | while (true) {
|
|---|
| 720 | do i++; while (dists[ids[i]] < tempDist);
|
|---|
| 721 | do j--; while (dists[ids[j]] > tempDist);
|
|---|
| 722 | if (j < i) break;
|
|---|
| 723 | swap(ids, i, j);
|
|---|
| 724 | }
|
|---|
| 725 | ids[left + 1] = ids[j];
|
|---|
| 726 | ids[j] = temp;
|
|---|
| 727 |
|
|---|
| 728 | if (right - i + 1 >= j - left) {
|
|---|
| 729 | quicksort(ids, dists, i, right);
|
|---|
| 730 | quicksort(ids, dists, left, j - 1);
|
|---|
| 731 | } else {
|
|---|
| 732 | quicksort(ids, dists, left, j - 1);
|
|---|
| 733 | quicksort(ids, dists, i, right);
|
|---|
| 734 | }
|
|---|
| 735 | }
|
|---|
| 736 | }
|
|---|
| 737 |
|
|---|
| 738 | function swap(arr, i, j) {
|
|---|
| 739 | const tmp = arr[i];
|
|---|
| 740 | arr[i] = arr[j];
|
|---|
| 741 | arr[j] = tmp;
|
|---|
| 742 | }
|
|---|
| 743 |
|
|---|
| 744 | function defaultGetX(p) {
|
|---|
| 745 | return p[0];
|
|---|
| 746 | }
|
|---|
| 747 | function defaultGetY(p) {
|
|---|
| 748 | return p[1];
|
|---|
| 749 | }
|
|---|
| 750 |
|
|---|
| 751 | return Delaunator;
|
|---|
| 752 |
|
|---|
| 753 | }));
|
|---|