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- import {epsilon, splitter, resulterrbound, estimate, vec, sum} from './util.js';
-
- const ccwerrboundA = (3 + 16 * epsilon) * epsilon;
- const ccwerrboundB = (2 + 12 * epsilon) * epsilon;
- const ccwerrboundC = (9 + 64 * epsilon) * epsilon * epsilon;
-
- const B = vec(4);
- const C1 = vec(8);
- const C2 = vec(12);
- const D = vec(16);
- const u = vec(4);
-
- function orient2dadapt(ax, ay, bx, by, cx, cy, detsum) {
- let acxtail, acytail, bcxtail, bcytail;
- let bvirt, c, ahi, alo, bhi, blo, _i, _j, _0, s1, s0, t1, t0, u3;
-
- const acx = ax - cx;
- const bcx = bx - cx;
- const acy = ay - cy;
- const bcy = by - cy;
-
- s1 = acx * bcy;
- c = splitter * acx;
- ahi = c - (c - acx);
- alo = acx - ahi;
- c = splitter * bcy;
- bhi = c - (c - bcy);
- blo = bcy - bhi;
- s0 = alo * blo - (s1 - ahi * bhi - alo * bhi - ahi * blo);
- t1 = acy * bcx;
- c = splitter * acy;
- ahi = c - (c - acy);
- alo = acy - ahi;
- c = splitter * bcx;
- bhi = c - (c - bcx);
- blo = bcx - bhi;
- t0 = alo * blo - (t1 - ahi * bhi - alo * bhi - ahi * blo);
- _i = s0 - t0;
- bvirt = s0 - _i;
- B[0] = s0 - (_i + bvirt) + (bvirt - t0);
- _j = s1 + _i;
- bvirt = _j - s1;
- _0 = s1 - (_j - bvirt) + (_i - bvirt);
- _i = _0 - t1;
- bvirt = _0 - _i;
- B[1] = _0 - (_i + bvirt) + (bvirt - t1);
- u3 = _j + _i;
- bvirt = u3 - _j;
- B[2] = _j - (u3 - bvirt) + (_i - bvirt);
- B[3] = u3;
-
- let det = estimate(4, B);
- let errbound = ccwerrboundB * detsum;
- if (det >= errbound || -det >= errbound) {
- return det;
- }
-
- bvirt = ax - acx;
- acxtail = ax - (acx + bvirt) + (bvirt - cx);
- bvirt = bx - bcx;
- bcxtail = bx - (bcx + bvirt) + (bvirt - cx);
- bvirt = ay - acy;
- acytail = ay - (acy + bvirt) + (bvirt - cy);
- bvirt = by - bcy;
- bcytail = by - (bcy + bvirt) + (bvirt - cy);
-
- if (acxtail === 0 && acytail === 0 && bcxtail === 0 && bcytail === 0) {
- return det;
- }
-
- errbound = ccwerrboundC * detsum + resulterrbound * Math.abs(det);
- det += (acx * bcytail + bcy * acxtail) - (acy * bcxtail + bcx * acytail);
- if (det >= errbound || -det >= errbound) return det;
-
- s1 = acxtail * bcy;
- c = splitter * acxtail;
- ahi = c - (c - acxtail);
- alo = acxtail - ahi;
- c = splitter * bcy;
- bhi = c - (c - bcy);
- blo = bcy - bhi;
- s0 = alo * blo - (s1 - ahi * bhi - alo * bhi - ahi * blo);
- t1 = acytail * bcx;
- c = splitter * acytail;
- ahi = c - (c - acytail);
- alo = acytail - ahi;
- c = splitter * bcx;
- bhi = c - (c - bcx);
- blo = bcx - bhi;
- t0 = alo * blo - (t1 - ahi * bhi - alo * bhi - ahi * blo);
- _i = s0 - t0;
- bvirt = s0 - _i;
- u[0] = s0 - (_i + bvirt) + (bvirt - t0);
- _j = s1 + _i;
- bvirt = _j - s1;
- _0 = s1 - (_j - bvirt) + (_i - bvirt);
- _i = _0 - t1;
- bvirt = _0 - _i;
- u[1] = _0 - (_i + bvirt) + (bvirt - t1);
- u3 = _j + _i;
- bvirt = u3 - _j;
- u[2] = _j - (u3 - bvirt) + (_i - bvirt);
- u[3] = u3;
- const C1len = sum(4, B, 4, u, C1);
-
- s1 = acx * bcytail;
- c = splitter * acx;
- ahi = c - (c - acx);
- alo = acx - ahi;
- c = splitter * bcytail;
- bhi = c - (c - bcytail);
- blo = bcytail - bhi;
- s0 = alo * blo - (s1 - ahi * bhi - alo * bhi - ahi * blo);
- t1 = acy * bcxtail;
- c = splitter * acy;
- ahi = c - (c - acy);
- alo = acy - ahi;
- c = splitter * bcxtail;
- bhi = c - (c - bcxtail);
- blo = bcxtail - bhi;
- t0 = alo * blo - (t1 - ahi * bhi - alo * bhi - ahi * blo);
- _i = s0 - t0;
- bvirt = s0 - _i;
- u[0] = s0 - (_i + bvirt) + (bvirt - t0);
- _j = s1 + _i;
- bvirt = _j - s1;
- _0 = s1 - (_j - bvirt) + (_i - bvirt);
- _i = _0 - t1;
- bvirt = _0 - _i;
- u[1] = _0 - (_i + bvirt) + (bvirt - t1);
- u3 = _j + _i;
- bvirt = u3 - _j;
- u[2] = _j - (u3 - bvirt) + (_i - bvirt);
- u[3] = u3;
- const C2len = sum(C1len, C1, 4, u, C2);
-
- s1 = acxtail * bcytail;
- c = splitter * acxtail;
- ahi = c - (c - acxtail);
- alo = acxtail - ahi;
- c = splitter * bcytail;
- bhi = c - (c - bcytail);
- blo = bcytail - bhi;
- s0 = alo * blo - (s1 - ahi * bhi - alo * bhi - ahi * blo);
- t1 = acytail * bcxtail;
- c = splitter * acytail;
- ahi = c - (c - acytail);
- alo = acytail - ahi;
- c = splitter * bcxtail;
- bhi = c - (c - bcxtail);
- blo = bcxtail - bhi;
- t0 = alo * blo - (t1 - ahi * bhi - alo * bhi - ahi * blo);
- _i = s0 - t0;
- bvirt = s0 - _i;
- u[0] = s0 - (_i + bvirt) + (bvirt - t0);
- _j = s1 + _i;
- bvirt = _j - s1;
- _0 = s1 - (_j - bvirt) + (_i - bvirt);
- _i = _0 - t1;
- bvirt = _0 - _i;
- u[1] = _0 - (_i + bvirt) + (bvirt - t1);
- u3 = _j + _i;
- bvirt = u3 - _j;
- u[2] = _j - (u3 - bvirt) + (_i - bvirt);
- u[3] = u3;
- const Dlen = sum(C2len, C2, 4, u, D);
-
- return D[Dlen - 1];
- }
-
- export function orient2d(ax, ay, bx, by, cx, cy) {
- const detleft = (ay - cy) * (bx - cx);
- const detright = (ax - cx) * (by - cy);
- const det = detleft - detright;
-
- const detsum = Math.abs(detleft + detright);
- if (Math.abs(det) >= ccwerrboundA * detsum) return det;
-
- return -orient2dadapt(ax, ay, bx, by, cx, cy, detsum);
- }
-
- export function orient2dfast(ax, ay, bx, by, cx, cy) {
- return (ay - cy) * (bx - cx) - (ax - cx) * (by - cy);
- }
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