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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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