al/filter.h

   1 #ifndef AL_FILTER_H
   2 #define AL_FILTER_H
   3
   4 #include <array>
   5 #include <cstdint>
   6 #include <string_view>
   7 #include <utility>
   8 #include <variant>
   9
  10 #include "AL/al.h"
  11 #include "AL/alc.h"
  12 #include "AL/efx.h"
  13
  14 #include "almalloc.h"
  15 #include "alnumeric.h"
  16
  17
  18 inline constexpr float LowPassFreqRef{5000.0f};
  19 inline constexpr float HighPassFreqRef{250.0f};
  20
  21 template<typename T>
  22 struct FilterTable {
  23     static void setParami(struct ALfilter*, ALenum, int);
  24     static void setParamiv(struct ALfilter*, ALenum, const int*);
  25     static void setParamf(struct ALfilter*, ALenum, float);
  26     static void setParamfv(struct ALfilter*, ALenum, const float*);
  27
  28     static void getParami(const struct ALfilter*, ALenum, int*);
  29     static void getParamiv(const struct ALfilter*, ALenum, int*);
  30     static void getParamf(const struct ALfilter*, ALenum, float*);
  31     static void getParamfv(const struct ALfilter*, ALenum, float*);
  32
  33 private:
  34     FilterTable() = default;
  35     friend T;
  36 };
  37
  38 struct NullFilterTable : public FilterTable<NullFilterTable> { };
  39 struct LowpassFilterTable : public FilterTable<LowpassFilterTable> { };
  40 struct HighpassFilterTable : public FilterTable<HighpassFilterTable> { };
  41 struct BandpassFilterTable : public FilterTable<BandpassFilterTable> { };
  42
  43
  44 struct ALfilter {
  45     ALenum type{AL_FILTER_NULL};
  46
  47     float Gain{1.0f};
  48     float GainHF{1.0f};
  49     float HFReference{LowPassFreqRef};
  50     float GainLF{1.0f};
  51     float LFReference{HighPassFreqRef};
  52
  53     using TableTypes = std::variant<NullFilterTable,LowpassFilterTable,HighpassFilterTable,
  54         BandpassFilterTable>;
  55     TableTypes mTypeVariant;
  56
  57     /* Self ID */
  58     ALuint id{0};
  59
  60     static void SetName(ALCcontext *context, ALuint id, std::string_view name);
  61
  62     DISABLE_ALLOC
  63 };
  64
  65 struct FilterSubList {
  66     uint64_t FreeMask{~0_u64};
  67     gsl::owner<std::array<ALfilter,64>*> Filters{nullptr};
  68
  69     FilterSubList() noexcept = default;
  70     FilterSubList(const FilterSubList&) = delete;
  71     FilterSubList(FilterSubList&& rhs) noexcept : FreeMask{rhs.FreeMask}, Filters{rhs.Filters}
  72     { rhs.FreeMask = ~0_u64; rhs.Filters = nullptr; }
  73     ~FilterSubList();
  74
  75     FilterSubList& operator=(const FilterSubList&) = delete;
  76     FilterSubList& operator=(FilterSubList&& rhs) noexcept
  77     { std::swap(FreeMask, rhs.FreeMask); std::swap(Filters, rhs.Filters); return *this; }
  78 };
  79
  80 #endif