#ifndef Magnum_Examples_FluidSimulation3D_SPH_DomainBox_h
#define Magnum_Examples_FluidSimulation3D_SPH_DomainBox_h
/*
This file is part of Magnum.
Original authors — credit is appreciated but not required:
2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019,
2020, 2021, 2022, 2023, 2024 — Vladimír Vondruš <mosra@centrum.cz>
2019 — Nghia Truong <nghiatruong.vn@gmail.com>
This is free and unencumbered software released into the public domain.
Anyone is free to copy, modify, publish, use, compile, sell, or distribute
this software, either in source code form or as a compiled binary, for any
purpose, commercial or non-commercial, and by any means.
In jurisdictions that recognize copyright laws, the author or authors of
this software dedicate any and all copyright interest in the software to
the public domain. We make this dedication for the benefit of the public
at large and to the detriment of our heirs and successors. We intend this
dedication to be an overt act of relinquishment in perpetuity of all
present and future rights to this software under copyright law.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include <vector>
#include <Corrade/Utility/Assert.h>
#include <Magnum/Magnum.h>
#include <Magnum/Math/Functions.h>
#include <Magnum/Math/Vector3.h>
namespace Magnum { namespace Examples {
/* A grid data structure to search for indices of particle neighbors within a
given distance. Upon searching for neighbors, the relative positions with
neighbors are also computed. */
class DomainBox {
public:
explicit DomainBox(Float particleRadius, const Vector3& lowerDomainBound, const Vector3& upperDomainBound);
Vector3& lowerDomainBound() { return _lowerDomainBound; }
Vector3& upperDomainBound() { return _upperDomainBound; }
void findNeighbors(const std::vector<Vector3>& positions,
std::vector<std::vector<uint32_t>>& neighbors,
std::vector<std::vector<Vector3>>& relativePositions);
bool enforceBoundary(Vector3& ppos, Vector3& pvel, Float restitution);
private:
void generateBoundaryParticles();
void collectIndices(const std::vector<Vector3>& positions);
void tightenGrid(const std::vector<Vector3>& positions);
template<Int d> bool isValidIndex(int idx) {
return idx >= 0 && static_cast<uint32_t>(idx) < _gridSize[d];
}
Vector3i getCellIndex(const Vector3& ppos) {
Vector3i cellIdx{NoInit};
for(std::size_t i = 0; i != 3; ++i) {
cellIdx[i] = Int((ppos[i] - _lowerGridBound[i]) * _invCellLength);
}
CORRADE_INTERNAL_ASSERT(isValidIndex<0>(cellIdx[0]) &&
isValidIndex<1>(cellIdx[1]) && isValidIndex<2>(cellIdx[2]));
return cellIdx;
}
UnsignedInt getFlatIndex(Int i, Int j, Int k) {
const UnsignedInt flatIndex =
UnsignedInt(i) +
UnsignedInt(j)*_gridSize[0] +
UnsignedInt(k)*_gridSize[0]*_gridSize[1];
CORRADE_INTERNAL_ASSERT(flatIndex < _cells.size());
return flatIndex;
}
std::vector<std::vector<UnsignedInt>> _cells;
std::vector<Vector3> _boundaryParticles;
Vector3 _lowerDomainBound, _upperDomainBound;
Vector3 _lowerGridBound;
Vector3 _upperGridBound;
UnsignedInt _gridSize[3] {1u, 1u, 1u};
Float _cellLength = 1.0f;
Float _maxDistSqr = 1.0f;
Float _invCellLength = 1.0f;
Float _particleRadius = 1.0f;
Float _overlappedDistSqr = 1.0e-4f;
};
}}
#endif