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(function (global, factory) { |
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typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory() : |
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typeof define === 'function' && define.amd ? define(factory) : |
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(global = typeof globalThis !== 'undefined' ? globalThis : global || self, global.Delaunator = factory()); |
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})(this, (function () { 'use strict'; |
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|
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const epsilon = 1.1102230246251565e-16; |
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const splitter = 134217729; |
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const resulterrbound = (3 + 8 * epsilon) * epsilon; |
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|
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function sum(elen, e, flen, f, h) { |
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let Q, Qnew, hh, bvirt; |
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let enow = e[0]; |
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let fnow = f[0]; |
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let eindex = 0; |
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let findex = 0; |
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if ((fnow > enow) === (fnow > -enow)) { |
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Q = enow; |
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enow = e[++eindex]; |
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} else { |
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Q = fnow; |
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fnow = f[++findex]; |
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} |
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let hindex = 0; |
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if (eindex < elen && findex < flen) { |
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if ((fnow > enow) === (fnow > -enow)) { |
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Qnew = enow + Q; |
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hh = Q - (Qnew - enow); |
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enow = e[++eindex]; |
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} else { |
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Qnew = fnow + Q; |
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hh = Q - (Qnew - fnow); |
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fnow = f[++findex]; |
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} |
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Q = Qnew; |
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if (hh !== 0) { |
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h[hindex++] = hh; |
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} |
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while (eindex < elen && findex < flen) { |
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if ((fnow > enow) === (fnow > -enow)) { |
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Qnew = Q + enow; |
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bvirt = Qnew - Q; |
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hh = Q - (Qnew - bvirt) + (enow - bvirt); |
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enow = e[++eindex]; |
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} else { |
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Qnew = Q + fnow; |
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bvirt = Qnew - Q; |
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hh = Q - (Qnew - bvirt) + (fnow - bvirt); |
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fnow = f[++findex]; |
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} |
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Q = Qnew; |
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if (hh !== 0) { |
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h[hindex++] = hh; |
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} |
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} |
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} |
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while (eindex < elen) { |
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Qnew = Q + enow; |
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bvirt = Qnew - Q; |
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hh = Q - (Qnew - bvirt) + (enow - bvirt); |
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enow = e[++eindex]; |
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Q = Qnew; |
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if (hh !== 0) { |
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h[hindex++] = hh; |
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} |
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} |
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while (findex < flen) { |
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Qnew = Q + fnow; |
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bvirt = Qnew - Q; |
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hh = Q - (Qnew - bvirt) + (fnow - bvirt); |
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fnow = f[++findex]; |
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Q = Qnew; |
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if (hh !== 0) { |
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h[hindex++] = hh; |
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} |
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} |
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if (Q !== 0 || hindex === 0) { |
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h[hindex++] = Q; |
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} |
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return hindex; |
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} |
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|
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function estimate(elen, e) { |
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let Q = e[0]; |
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for (let i = 1; i < elen; i++) Q += e[i]; |
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return Q; |
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} |
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function vec(n) { |
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return new Float64Array(n); |
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} |
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const ccwerrboundA = (3 + 16 * epsilon) * epsilon; |
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const ccwerrboundB = (2 + 12 * epsilon) * epsilon; |
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const ccwerrboundC = (9 + 64 * epsilon) * epsilon * epsilon; |
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const B = vec(4); |
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const C1 = vec(8); |
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const C2 = vec(12); |
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const D = vec(16); |
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const u = vec(4); |
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function orient2dadapt(ax, ay, bx, by, cx, cy, detsum) { |
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let acxtail, acytail, bcxtail, bcytail; |
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let bvirt, c, ahi, alo, bhi, blo, _i, _j, _0, s1, s0, t1, t0, u3; |
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const acx = ax - cx; |
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const bcx = bx - cx; |
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const acy = ay - cy; |
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const bcy = by - cy; |
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s1 = acx * bcy; |
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c = splitter * acx; |
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ahi = c - (c - acx); |
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alo = acx - ahi; |
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c = splitter * bcy; |
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bhi = c - (c - bcy); |
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blo = bcy - bhi; |
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s0 = alo * blo - (s1 - ahi * bhi - alo * bhi - ahi * blo); |
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t1 = acy * bcx; |
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c = splitter * acy; |
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ahi = c - (c - acy); |
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alo = acy - ahi; |
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c = splitter * bcx; |
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bhi = c - (c - bcx); |
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blo = bcx - bhi; |
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t0 = alo * blo - (t1 - ahi * bhi - alo * bhi - ahi * blo); |
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_i = s0 - t0; |
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bvirt = s0 - _i; |
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B[0] = s0 - (_i + bvirt) + (bvirt - t0); |
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_j = s1 + _i; |
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bvirt = _j - s1; |
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_0 = s1 - (_j - bvirt) + (_i - bvirt); |
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_i = _0 - t1; |
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bvirt = _0 - _i; |
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B[1] = _0 - (_i + bvirt) + (bvirt - t1); |
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u3 = _j + _i; |
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bvirt = u3 - _j; |
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B[2] = _j - (u3 - bvirt) + (_i - bvirt); |
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B[3] = u3; |
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let det = estimate(4, B); |
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let errbound = ccwerrboundB * detsum; |
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if (det >= errbound || -det >= errbound) { |
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return det; |
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} |
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bvirt = ax - acx; |
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acxtail = ax - (acx + bvirt) + (bvirt - cx); |
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bvirt = bx - bcx; |
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bcxtail = bx - (bcx + bvirt) + (bvirt - cx); |
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bvirt = ay - acy; |
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acytail = ay - (acy + bvirt) + (bvirt - cy); |
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bvirt = by - bcy; |
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bcytail = by - (bcy + bvirt) + (bvirt - cy); |
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if (acxtail === 0 && acytail === 0 && bcxtail === 0 && bcytail === 0) { |
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return det; |
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} |
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errbound = ccwerrboundC * detsum + resulterrbound * Math.abs(det); |
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det += (acx * bcytail + bcy * acxtail) - (acy * bcxtail + bcx * acytail); |
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if (det >= errbound || -det >= errbound) return det; |
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s1 = acxtail * bcy; |
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c = splitter * acxtail; |
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ahi = c - (c - acxtail); |
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alo = acxtail - ahi; |
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c = splitter * bcy; |
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bhi = c - (c - bcy); |
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blo = bcy - bhi; |
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s0 = alo * blo - (s1 - ahi * bhi - alo * bhi - ahi * blo); |
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t1 = acytail * bcx; |
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c = splitter * acytail; |
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ahi = c - (c - acytail); |
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alo = acytail - ahi; |
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c = splitter * bcx; |
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bhi = c - (c - bcx); |
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blo = bcx - bhi; |
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t0 = alo * blo - (t1 - ahi * bhi - alo * bhi - ahi * blo); |
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_i = s0 - t0; |
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bvirt = s0 - _i; |
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u[0] = s0 - (_i + bvirt) + (bvirt - t0); |
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_j = s1 + _i; |
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bvirt = _j - s1; |
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_0 = s1 - (_j - bvirt) + (_i - bvirt); |
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_i = _0 - t1; |
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bvirt = _0 - _i; |
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u[1] = _0 - (_i + bvirt) + (bvirt - t1); |
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u3 = _j + _i; |
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bvirt = u3 - _j; |
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u[2] = _j - (u3 - bvirt) + (_i - bvirt); |
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u[3] = u3; |
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const C1len = sum(4, B, 4, u, C1); |
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s1 = acx * bcytail; |
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c = splitter * acx; |
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ahi = c - (c - acx); |
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alo = acx - ahi; |
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c = splitter * bcytail; |
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bhi = c - (c - bcytail); |
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blo = bcytail - bhi; |
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s0 = alo * blo - (s1 - ahi * bhi - alo * bhi - ahi * blo); |
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t1 = acy * bcxtail; |
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c = splitter * acy; |
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ahi = c - (c - acy); |
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alo = acy - ahi; |
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c = splitter * bcxtail; |
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bhi = c - (c - bcxtail); |
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blo = bcxtail - bhi; |
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t0 = alo * blo - (t1 - ahi * bhi - alo * bhi - ahi * blo); |
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_i = s0 - t0; |
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bvirt = s0 - _i; |
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u[0] = s0 - (_i + bvirt) + (bvirt - t0); |
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_j = s1 + _i; |
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bvirt = _j - s1; |
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_0 = s1 - (_j - bvirt) + (_i - bvirt); |
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_i = _0 - t1; |
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bvirt = _0 - _i; |
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u[1] = _0 - (_i + bvirt) + (bvirt - t1); |
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u3 = _j + _i; |
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bvirt = u3 - _j; |
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u[2] = _j - (u3 - bvirt) + (_i - bvirt); |
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u[3] = u3; |
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const C2len = sum(C1len, C1, 4, u, C2); |
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s1 = acxtail * bcytail; |
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c = splitter * acxtail; |
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ahi = c - (c - acxtail); |
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alo = acxtail - ahi; |
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c = splitter * bcytail; |
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bhi = c - (c - bcytail); |
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blo = bcytail - bhi; |
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s0 = alo * blo - (s1 - ahi * bhi - alo * bhi - ahi * blo); |
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t1 = acytail * bcxtail; |
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c = splitter * acytail; |
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ahi = c - (c - acytail); |
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alo = acytail - ahi; |
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c = splitter * bcxtail; |
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bhi = c - (c - bcxtail); |
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blo = bcxtail - bhi; |
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t0 = alo * blo - (t1 - ahi * bhi - alo * bhi - ahi * blo); |
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_i = s0 - t0; |
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bvirt = s0 - _i; |
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u[0] = s0 - (_i + bvirt) + (bvirt - t0); |
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_j = s1 + _i; |
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bvirt = _j - s1; |
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_0 = s1 - (_j - bvirt) + (_i - bvirt); |
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_i = _0 - t1; |
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bvirt = _0 - _i; |
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u[1] = _0 - (_i + bvirt) + (bvirt - t1); |
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u3 = _j + _i; |
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bvirt = u3 - _j; |
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u[2] = _j - (u3 - bvirt) + (_i - bvirt); |
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u[3] = u3; |
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const Dlen = sum(C2len, C2, 4, u, D); |
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|
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return D[Dlen - 1]; |
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} |
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function orient2d(ax, ay, bx, by, cx, cy) { |
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const detleft = (ay - cy) * (bx - cx); |
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const detright = (ax - cx) * (by - cy); |
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const det = detleft - detright; |
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const detsum = Math.abs(detleft + detright); |
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if (Math.abs(det) >= ccwerrboundA * detsum) return det; |
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return -orient2dadapt(ax, ay, bx, by, cx, cy, detsum); |
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} |
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const EPSILON = Math.pow(2, -52); |
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const EDGE_STACK = new Uint32Array(512); |
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class Delaunator { |
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static from(points, getX = defaultGetX, getY = defaultGetY) { |
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const n = points.length; |
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const coords = new Float64Array(n * 2); |
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for (let i = 0; i < n; i++) { |
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const p = points[i]; |
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coords[2 * i] = getX(p); |
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coords[2 * i + 1] = getY(p); |
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} |
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return new Delaunator(coords); |
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} |
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constructor(coords) { |
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const n = coords.length >> 1; |
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if (n > 0 && typeof coords[0] !== 'number') throw new Error('Expected coords to contain numbers.'); |
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this.coords = coords; |
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const maxTriangles = Math.max(2 * n - 5, 0); |
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this._triangles = new Uint32Array(maxTriangles * 3); |
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this._halfedges = new Int32Array(maxTriangles * 3); |
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this._hashSize = Math.ceil(Math.sqrt(n)); |
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this._hullPrev = new Uint32Array(n); |
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this._hullNext = new Uint32Array(n); |
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this._hullTri = new Uint32Array(n); |
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this._hullHash = new Int32Array(this._hashSize); |
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this._ids = new Uint32Array(n); |
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this._dists = new Float64Array(n); |
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this.update(); |
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} |
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update() { |
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const {coords, _hullPrev: hullPrev, _hullNext: hullNext, _hullTri: hullTri, _hullHash: hullHash} = this; |
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const n = coords.length >> 1; |
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let minX = Infinity; |
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let minY = Infinity; |
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let maxX = -Infinity; |
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let maxY = -Infinity; |
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for (let i = 0; i < n; i++) { |
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const x = coords[2 * i]; |
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const y = coords[2 * i + 1]; |
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if (x < minX) minX = x; |
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if (y < minY) minY = y; |
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if (x > maxX) maxX = x; |
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if (y > maxY) maxY = y; |
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this._ids[i] = i; |
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} |
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const cx = (minX + maxX) / 2; |
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const cy = (minY + maxY) / 2; |
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let i0, i1, i2; |
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for (let i = 0, minDist = Infinity; i < n; i++) { |
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const d = dist(cx, cy, coords[2 * i], coords[2 * i + 1]); |
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if (d < minDist) { |
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i0 = i; |
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minDist = d; |
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} |
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} |
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const i0x = coords[2 * i0]; |
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const i0y = coords[2 * i0 + 1]; |
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for (let i = 0, minDist = Infinity; i < n; i++) { |
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if (i === i0) continue; |
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const d = dist(i0x, i0y, coords[2 * i], coords[2 * i + 1]); |
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if (d < minDist && d > 0) { |
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i1 = i; |
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minDist = d; |
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} |
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} |
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let i1x = coords[2 * i1]; |
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let i1y = coords[2 * i1 + 1]; |
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let minRadius = Infinity; |
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for (let i = 0; i < n; i++) { |
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if (i === i0 || i === i1) continue; |
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const r = circumradius(i0x, i0y, i1x, i1y, coords[2 * i], coords[2 * i + 1]); |
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if (r < minRadius) { |
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i2 = i; |
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minRadius = r; |
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} |
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} |
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let i2x = coords[2 * i2]; |
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let i2y = coords[2 * i2 + 1]; |
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if (minRadius === Infinity) { |
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for (let i = 0; i < n; i++) { |
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this._dists[i] = (coords[2 * i] - coords[0]) || (coords[2 * i + 1] - coords[1]); |
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} |
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quicksort(this._ids, this._dists, 0, n - 1); |
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const hull = new Uint32Array(n); |
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let j = 0; |
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for (let i = 0, d0 = -Infinity; i < n; i++) { |
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const id = this._ids[i]; |
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const d = this._dists[id]; |
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if (d > d0) { |
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hull[j++] = id; |
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d0 = d; |
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} |
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} |
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this.hull = hull.subarray(0, j); |
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this.triangles = new Uint32Array(0); |
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this.halfedges = new Uint32Array(0); |
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return; |
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} |
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if (orient2d(i0x, i0y, i1x, i1y, i2x, i2y) < 0) { |
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const i = i1; |
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const x = i1x; |
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const y = i1y; |
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i1 = i2; |
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i1x = i2x; |
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i1y = i2y; |
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i2 = i; |
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i2x = x; |
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i2y = y; |
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} |
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const center = circumcenter(i0x, i0y, i1x, i1y, i2x, i2y); |
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this._cx = center.x; |
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this._cy = center.y; |
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for (let i = 0; i < n; i++) { |
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this._dists[i] = dist(coords[2 * i], coords[2 * i + 1], center.x, center.y); |
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} |
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quicksort(this._ids, this._dists, 0, n - 1); |
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this._hullStart = i0; |
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let hullSize = 3; |
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hullNext[i0] = hullPrev[i2] = i1; |
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hullNext[i1] = hullPrev[i0] = i2; |
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hullNext[i2] = hullPrev[i1] = i0; |
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hullTri[i0] = 0; |
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hullTri[i1] = 1; |
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hullTri[i2] = 2; |
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|
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hullHash.fill(-1); |
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hullHash[this._hashKey(i0x, i0y)] = i0; |
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hullHash[this._hashKey(i1x, i1y)] = i1; |
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hullHash[this._hashKey(i2x, i2y)] = i2; |
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this.trianglesLen = 0; |
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this._addTriangle(i0, i1, i2, -1, -1, -1); |
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for (let k = 0, xp, yp; k < this._ids.length; k++) { |
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const i = this._ids[k]; |
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const x = coords[2 * i]; |
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const y = coords[2 * i + 1]; |
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if (k > 0 && Math.abs(x - xp) <= EPSILON && Math.abs(y - yp) <= EPSILON) continue; |
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xp = x; |
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yp = y; |
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if (i === i0 || i === i1 || i === i2) continue; |
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|
|
let start = 0; |
|
for (let j = 0, key = this._hashKey(x, y); j < this._hashSize; j++) { |
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start = hullHash[(key + j) % this._hashSize]; |
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if (start !== -1 && start !== hullNext[start]) break; |
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} |
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|
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start = hullPrev[start]; |
|
let e = start, q; |
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while (q = hullNext[e], orient2d(x, y, coords[2 * e], coords[2 * e + 1], coords[2 * q], coords[2 * q + 1]) >= 0) { |
|
e = q; |
|
if (e === start) { |
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e = -1; |
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break; |
|
} |
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} |
|
if (e === -1) continue; |
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|
|
|
|
let t = this._addTriangle(e, i, hullNext[e], -1, -1, hullTri[e]); |
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|
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hullTri[i] = this._legalize(t + 2); |
|
hullTri[e] = t; |
|
hullSize++; |
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|
|
|
let n = hullNext[e]; |
|
while (q = hullNext[n], orient2d(x, y, coords[2 * n], coords[2 * n + 1], coords[2 * q], coords[2 * q + 1]) < 0) { |
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t = this._addTriangle(n, i, q, hullTri[i], -1, hullTri[n]); |
|
hullTri[i] = this._legalize(t + 2); |
|
hullNext[n] = n; |
|
hullSize--; |
|
n = q; |
|
} |
|
|
|
|
|
if (e === start) { |
|
while (q = hullPrev[e], orient2d(x, y, coords[2 * q], coords[2 * q + 1], coords[2 * e], coords[2 * e + 1]) < 0) { |
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t = this._addTriangle(q, i, e, -1, hullTri[e], hullTri[q]); |
|
this._legalize(t + 2); |
|
hullTri[q] = t; |
|
hullNext[e] = e; |
|
hullSize--; |
|
e = q; |
|
} |
|
} |
|
|
|
|
|
this._hullStart = hullPrev[i] = e; |
|
hullNext[e] = hullPrev[n] = i; |
|
hullNext[i] = n; |
|
|
|
|
|
hullHash[this._hashKey(x, y)] = i; |
|
hullHash[this._hashKey(coords[2 * e], coords[2 * e + 1])] = e; |
|
} |
|
|
|
this.hull = new Uint32Array(hullSize); |
|
for (let i = 0, e = this._hullStart; i < hullSize; i++) { |
|
this.hull[i] = e; |
|
e = hullNext[e]; |
|
} |
|
|
|
|
|
this.triangles = this._triangles.subarray(0, this.trianglesLen); |
|
this.halfedges = this._halfedges.subarray(0, this.trianglesLen); |
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} |
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|
|
_hashKey(x, y) { |
|
return Math.floor(pseudoAngle(x - this._cx, y - this._cy) * this._hashSize) % this._hashSize; |
|
} |
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|
|
_legalize(a) { |
|
const {_triangles: triangles, _halfedges: halfedges, coords} = this; |
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|
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let i = 0; |
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let ar = 0; |
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|
|
|
|
while (true) { |
|
const b = halfedges[a]; |
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
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|
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|
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|
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const a0 = a - a % 3; |
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ar = a0 + (a + 2) % 3; |
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|
|
if (b === -1) { |
|
if (i === 0) break; |
|
a = EDGE_STACK[--i]; |
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continue; |
|
} |
|
|
|
const b0 = b - b % 3; |
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const al = a0 + (a + 1) % 3; |
|
const bl = b0 + (b + 2) % 3; |
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|
|
const p0 = triangles[ar]; |
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const pr = triangles[a]; |
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const pl = triangles[al]; |
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const p1 = triangles[bl]; |
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|
|
const illegal = inCircle( |
|
coords[2 * p0], coords[2 * p0 + 1], |
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coords[2 * pr], coords[2 * pr + 1], |
|
coords[2 * pl], coords[2 * pl + 1], |
|
coords[2 * p1], coords[2 * p1 + 1]); |
|
|
|
if (illegal) { |
|
triangles[a] = p1; |
|
triangles[b] = p0; |
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|
|
const hbl = halfedges[bl]; |
|
|
|
|
|
if (hbl === -1) { |
|
let e = this._hullStart; |
|
do { |
|
if (this._hullTri[e] === bl) { |
|
this._hullTri[e] = a; |
|
break; |
|
} |
|
e = this._hullPrev[e]; |
|
} while (e !== this._hullStart); |
|
} |
|
this._link(a, hbl); |
|
this._link(b, halfedges[ar]); |
|
this._link(ar, bl); |
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|
|
const br = b0 + (b + 1) % 3; |
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|
|
|
|
if (i < EDGE_STACK.length) { |
|
EDGE_STACK[i++] = br; |
|
} |
|
} else { |
|
if (i === 0) break; |
|
a = EDGE_STACK[--i]; |
|
} |
|
} |
|
|
|
return ar; |
|
} |
|
|
|
_link(a, b) { |
|
this._halfedges[a] = b; |
|
if (b !== -1) this._halfedges[b] = a; |
|
} |
|
|
|
|
|
_addTriangle(i0, i1, i2, a, b, c) { |
|
const t = this.trianglesLen; |
|
|
|
this._triangles[t] = i0; |
|
this._triangles[t + 1] = i1; |
|
this._triangles[t + 2] = i2; |
|
|
|
this._link(t, a); |
|
this._link(t + 1, b); |
|
this._link(t + 2, c); |
|
|
|
this.trianglesLen += 3; |
|
|
|
return t; |
|
} |
|
} |
|
|
|
|
|
function pseudoAngle(dx, dy) { |
|
const p = dx / (Math.abs(dx) + Math.abs(dy)); |
|
return (dy > 0 ? 3 - p : 1 + p) / 4; |
|
} |
|
|
|
function dist(ax, ay, bx, by) { |
|
const dx = ax - bx; |
|
const dy = ay - by; |
|
return dx * dx + dy * dy; |
|
} |
|
|
|
function inCircle(ax, ay, bx, by, cx, cy, px, py) { |
|
const dx = ax - px; |
|
const dy = ay - py; |
|
const ex = bx - px; |
|
const ey = by - py; |
|
const fx = cx - px; |
|
const fy = cy - py; |
|
|
|
const ap = dx * dx + dy * dy; |
|
const bp = ex * ex + ey * ey; |
|
const cp = fx * fx + fy * fy; |
|
|
|
return dx * (ey * cp - bp * fy) - |
|
dy * (ex * cp - bp * fx) + |
|
ap * (ex * fy - ey * fx) < 0; |
|
} |
|
|
|
function circumradius(ax, ay, bx, by, cx, cy) { |
|
const dx = bx - ax; |
|
const dy = by - ay; |
|
const ex = cx - ax; |
|
const ey = cy - ay; |
|
|
|
const bl = dx * dx + dy * dy; |
|
const cl = ex * ex + ey * ey; |
|
const d = 0.5 / (dx * ey - dy * ex); |
|
|
|
const x = (ey * bl - dy * cl) * d; |
|
const y = (dx * cl - ex * bl) * d; |
|
|
|
return x * x + y * y; |
|
} |
|
|
|
function circumcenter(ax, ay, bx, by, cx, cy) { |
|
const dx = bx - ax; |
|
const dy = by - ay; |
|
const ex = cx - ax; |
|
const ey = cy - ay; |
|
|
|
const bl = dx * dx + dy * dy; |
|
const cl = ex * ex + ey * ey; |
|
const d = 0.5 / (dx * ey - dy * ex); |
|
|
|
const x = ax + (ey * bl - dy * cl) * d; |
|
const y = ay + (dx * cl - ex * bl) * d; |
|
|
|
return {x, y}; |
|
} |
|
|
|
function quicksort(ids, dists, left, right) { |
|
if (right - left <= 20) { |
|
for (let i = left + 1; i <= right; i++) { |
|
const temp = ids[i]; |
|
const tempDist = dists[temp]; |
|
let j = i - 1; |
|
while (j >= left && dists[ids[j]] > tempDist) ids[j + 1] = ids[j--]; |
|
ids[j + 1] = temp; |
|
} |
|
} else { |
|
const median = (left + right) >> 1; |
|
let i = left + 1; |
|
let j = right; |
|
swap(ids, median, i); |
|
if (dists[ids[left]] > dists[ids[right]]) swap(ids, left, right); |
|
if (dists[ids[i]] > dists[ids[right]]) swap(ids, i, right); |
|
if (dists[ids[left]] > dists[ids[i]]) swap(ids, left, i); |
|
|
|
const temp = ids[i]; |
|
const tempDist = dists[temp]; |
|
while (true) { |
|
do i++; while (dists[ids[i]] < tempDist); |
|
do j--; while (dists[ids[j]] > tempDist); |
|
if (j < i) break; |
|
swap(ids, i, j); |
|
} |
|
ids[left + 1] = ids[j]; |
|
ids[j] = temp; |
|
|
|
if (right - i + 1 >= j - left) { |
|
quicksort(ids, dists, i, right); |
|
quicksort(ids, dists, left, j - 1); |
|
} else { |
|
quicksort(ids, dists, left, j - 1); |
|
quicksort(ids, dists, i, right); |
|
} |
|
} |
|
} |
|
|
|
function swap(arr, i, j) { |
|
const tmp = arr[i]; |
|
arr[i] = arr[j]; |
|
arr[j] = tmp; |
|
} |
|
|
|
function defaultGetX(p) { |
|
return p[0]; |
|
} |
|
function defaultGetY(p) { |
|
return p[1]; |
|
} |
|
|
|
return Delaunator; |
|
|
|
})); |
|
|