diff options
Diffstat (limited to 'OpenAL32')
| -rw-r--r-- | OpenAL32/Include/alFilter.h | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/OpenAL32/Include/alFilter.h b/OpenAL32/Include/alFilter.h index 40fff4fd..c0a05d6a 100644 --- a/OpenAL32/Include/alFilter.h +++ b/OpenAL32/Include/alFilter.h @@ -13,6 +13,39 @@ typedef struct { ALfloat history[0]; } FILTER; +static __inline ALfloat lpFilter4P(FILTER *iir, ALuint offset, ALfloat input) +{ + ALfloat *history = &iir->history[offset]; + ALfloat a = iir->coeff; + ALfloat output = input; + + output = output + (history[0]-output)*a; + history[0] = output; + output = output + (history[1]-output)*a; + history[1] = output; + output = output + (history[2]-output)*a; + history[2] = output; + output = output + (history[3]-output)*a; + history[3] = output; + + return output; +} + +static __inline ALfloat lpFilter2P(FILTER *iir, ALuint offset, ALfloat input) +{ + ALfloat *history = &iir->history[offset]; + ALfloat a = iir->coeff; + ALfloat output = input; + + output = output + (history[0]-output)*a; + history[0] = output; + output = output + (history[1]-output)*a; + history[1] = output; + + return output; +} + + #define AL_FILTER_TYPE 0x8001 #define AL_FILTER_NULL 0x0000 |