core/cubic_tables.h

   1 #ifndef CORE_CUBIC_TABLES_H
   2 #define CORE_CUBIC_TABLES_H
   3
   4 #include <array>
   5 #include <cstddef>
   6
   7 #include "cubic_defs.h"
   8 #include "opthelpers.h"
   9
  10
  11 struct SIMDALIGN CubicTable {
  12     std::array<CubicCoefficients,CubicPhaseCount> mTable{};
  13 };
  14
  15 struct GaussianTable : CubicTable { GaussianTable(); };
  16 inline const GaussianTable gGaussianFilter;
  17
  18 struct SplineTable : CubicTable { SplineTable(); };
  19 inline const SplineTable gSplineFilter;
  20
  21
  22 struct CubicFilter {
  23     static constexpr std::size_t sTableBits{8};
  24     static constexpr std::size_t sTableSteps{1 << sTableBits};
  25     static constexpr std::size_t sTableMask{sTableSteps - 1};
  26
  27     std::array<float,sTableSteps*2 + 1> mFilter{};
  28
  29     CubicFilter();
  30
  31     [[nodiscard]] constexpr
  32     auto getCoeff0(std::size_t i) const noexcept -> float { return mFilter[sTableSteps+i]; }
  33     [[nodiscard]] constexpr
  34     auto getCoeff1(std::size_t i) const noexcept -> float { return mFilter[i]; }
  35     [[nodiscard]] constexpr
  36     auto getCoeff2(std::size_t i) const noexcept -> float { return mFilter[sTableSteps-i]; }
  37     [[nodiscard]] constexpr
  38     auto getCoeff3(std::size_t i) const noexcept -> float { return mFilter[sTableSteps*2-i]; }
  39 };
  40 inline const CubicFilter gCubicTable;
  41
  42 #endif /* CORE_CUBIC_TABLES_H */