Function evalQSum

js/decimation.js:563–565

(q, v1, v2, x, y, z)

      const d = -(px*positions[va*3] + py*positions[va*3+1] + pz*positions[va*3+2]);
      // Scale by sqrtW: addPlaneQ accumulates (a²,ab,…) so scaling inputs by √w yields w×(a²,ab,…)
      addPlaneQ(quadrics, va, px*sqrtW, py*sqrtW, pz*sqrtW, d*sqrtW);
      addPlaneQ(quadrics, vb, px*sqrtW, py*sqrtW, pz*sqrtW, d*sqrtW);
    }
  }
}