Alc/hrtf.h

   1 #ifndef ALC_HRTF_H
   2 #define ALC_HRTF_H
   3
   4 #include "AL/al.h"
   5 #include "AL/alc.h"
   6
   7 #include "alstring.h"
   8
   9
  10 struct Hrtf {
  11     ALuint sampleRate;
  12     ALuint irSize;
  13     ALubyte evCount;
  14
  15     const ALubyte *azCount;
  16     const ALushort *evOffset;
  17     const ALshort *coeffs;
  18     const ALubyte *delays;
  19
  20     const char *filename;
  21     struct Hrtf *next;
  22 };
  23
  24 typedef struct HrtfEntry {
  25     al_string name;
  26
  27     const struct Hrtf *hrtf;
  28 } HrtfEntry;
  29 TYPEDEF_VECTOR(HrtfEntry, vector_HrtfEntry)
  30
  31 #define HRIR_BITS        (7)
  32 #define HRIR_LENGTH      (1<<HRIR_BITS)
  33 #define HRIR_MASK        (HRIR_LENGTH-1)
  34 #define HRTFDELAY_BITS    (20)
  35 #define HRTFDELAY_FRACONE (1<<HRTFDELAY_BITS)
  36 #define HRTFDELAY_MASK    (HRTFDELAY_FRACONE-1)
  37
  38 void FreeHrtfs(void);
  39
  40 vector_HrtfEntry EnumerateHrtf(const_al_string devname);
  41 void FreeHrtfList(vector_HrtfEntry *list);
  42
  43 void GetLerpedHrtfCoeffs(const struct Hrtf *Hrtf, ALfloat elevation, ALfloat azimuth, ALfloat spread, ALfloat gain, ALfloat (*coeffs)[2], ALuint *delays);
  44
  45 /* Produces HRTF filter coefficients for decoding B-Format. The result will
  46  * have ACN ordering with N3D normalization. NumChannels must currently be 4,
  47  * for first-order. Returns the maximum impulse-response length of the
  48  * generated coefficients.
  49  */
  50 ALuint BuildBFormatHrtf(const struct Hrtf *Hrtf, ALfloat (*coeffs)[HRIR_LENGTH][2], ALuint NumChannels);
  51
  52 #endif /* ALC_HRTF_H */