BambuStudio/libslic3r/Arachne/utils/SparsePointGrid.hpp

91 lines
3.1 KiB
C++

// Copyright (c) 2016 Scott Lenser
// Copyright (c) 2020 Ultimaker B.V.
// CuraEngine is released under the terms of the AGPLv3 or higher.
#ifndef UTILS_SPARSE_POINT_GRID_H
#define UTILS_SPARSE_POINT_GRID_H
#include <cassert>
#include <unordered_map>
#include <vector>
#include "SparseGrid.hpp"
namespace Slic3r::Arachne {
/*! \brief Sparse grid which can locate spatially nearby elements efficiently.
*
* \tparam ElemT The element type to store.
* \tparam Locator The functor to get the location from ElemT. Locator
* must have: Point operator()(const ElemT &elem) const
* which returns the location associated with val.
*/
template<class ElemT, class Locator> class SparsePointGrid : public SparseGrid<ElemT>
{
public:
using Elem = ElemT;
/*! \brief Constructs a sparse grid with the specified cell size.
*
* \param[in] cell_size The size to use for a cell (square) in the grid.
* Typical values would be around 0.5-2x of expected query radius.
* \param[in] elem_reserve Number of elements to research space for.
* \param[in] max_load_factor Maximum average load factor before rehashing.
*/
SparsePointGrid(coord_t cell_size, size_t elem_reserve = 0U, float max_load_factor = 1.0f);
/*! \brief Inserts elem into the sparse grid.
*
* \param[in] elem The element to be inserted.
*/
void insert(const Elem &elem);
/*!
* Get just any element that's within a certain radius of a point.
*
* Rather than giving a vector of nearby elements, this function just gives
* a single element, any element, in no particular order.
* \param query_pt The point to query for an object nearby.
* \param radius The radius of what is considered "nearby".
*/
const ElemT *getAnyNearby(const Point &query_pt, coord_t radius);
protected:
using GridPoint = typename SparseGrid<ElemT>::GridPoint;
/*! \brief Accessor for getting locations from elements. */
Locator m_locator;
};
template<class ElemT, class Locator>
SparsePointGrid<ElemT, Locator>::SparsePointGrid(coord_t cell_size, size_t elem_reserve, float max_load_factor) : SparseGrid<ElemT>(cell_size, elem_reserve, max_load_factor) {}
template<class ElemT, class Locator>
void SparsePointGrid<ElemT, Locator>::insert(const Elem &elem)
{
Point loc = m_locator(elem);
GridPoint grid_loc = SparseGrid<ElemT>::toGridPoint(loc.template cast<int64_t>());
SparseGrid<ElemT>::m_grid.emplace(grid_loc, elem);
}
template<class ElemT, class Locator>
const ElemT *SparsePointGrid<ElemT, Locator>::getAnyNearby(const Point &query_pt, coord_t radius)
{
const ElemT *ret = nullptr;
const std::function<bool(const ElemT &)> &process_func = [&ret, query_pt, radius, this](const ElemT &maybe_nearby) {
if (shorter_then(m_locator(maybe_nearby) - query_pt, radius)) {
ret = &maybe_nearby;
return false;
}
return true;
};
SparseGrid<ElemT>::processNearby(query_pt, radius, process_func);
return ret;
}
} // namespace Slic3r::Arachne
#endif // UTILS_SPARSE_POINT_GRID_H