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/**************************************************************************
* *
* Regina - A Normal Surface Theory Calculator *
* Computational Engine *
* *
* Copyright (c) 1999-2025, Ben Burton *
* For further details contact Ben Burton (bab@debian.org). *
* *
* This program is free software; you can redistribute it and/or *
* modify it under the terms of the GNU General Public License as *
* published by the Free Software Foundation; either version 2 of the *
* License, or (at your option) any later version. *
* *
* As an exception, when this program is distributed through (i) the *
* App Store by Apple Inc.; (ii) the Mac App Store by Apple Inc.; or *
* (iii) Google Play by Google Inc., then that store may impose any *
* digital rights management, device limits and/or redistribution *
* restrictions that are required by its terms of service. *
* *
* This program is distributed in the hope that it will be useful, but *
* WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU *
* General Public License for more details. *
* *
* You should have received a copy of the GNU General Public License *
* along with this program. If not, see <https://www.gnu.org/licenses/>. *
* *
**************************************************************************/
#include "algebra/abeliangroup.h"
#include "manifold/handlebody.h"
#include "triangulation/dim3.h"
#include "subcomplex/snappedball.h"
namespace regina {
std::unique_ptr<SnappedBall> SnappedBall::recognise(Tetrahedron<3>* tet) {
int inFace1, inFace2;
Perm<4> perm;
for (inFace1 = 0; inFace1 < 3; inFace1++)
if (tet->adjacentTetrahedron(inFace1) == tet) {
perm = tet->adjacentGluing(inFace1);
inFace2 = perm[inFace1];
if (perm == Perm<4>(inFace1, inFace2)) {
// This is it!
return std::unique_ptr<SnappedBall>(new SnappedBall(
tet, Edge<3>::edgeNumber[inFace1][inFace2]));
}
}
return nullptr;
}
std::unique_ptr<Manifold> SnappedBall::manifold() const {
return std::make_unique<Handlebody>(0);
}
AbelianGroup SnappedBall::homology() const {
return AbelianGroup();
}
} // namespace regina
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