diff options
Diffstat (limited to 'Alc/effects/echo.c')
| -rw-r--r-- | Alc/effects/echo.c | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/Alc/effects/echo.c b/Alc/effects/echo.c index 163b6ecb..4d2fd6f4 100644 --- a/Alc/effects/echo.c +++ b/Alc/effects/echo.c @@ -124,10 +124,14 @@ static ALvoid ALechoState_process(ALechoState *state, ALuint SamplesToDo, const const ALuint tap1 = state->Tap[0].delay; const ALuint tap2 = state->Tap[1].delay; ALuint offset = state->Offset; - ALfloat smp; + ALfloat x[2], y[2], in, out; ALuint base; ALuint i, k; + x[0] = state->Filter.x[0]; + x[1] = state->Filter.x[1]; + y[0] = state->Filter.y[0]; + y[1] = state->Filter.y[1]; for(base = 0;base < SamplesToDo;) { ALfloat temps[128][2]; @@ -142,8 +146,14 @@ static ALvoid ALechoState_process(ALechoState *state, ALuint SamplesToDo, const // Apply damping and feedback gain to the second tap, and mix in the // new sample - smp = ALfilterState_processSingle(&state->Filter, temps[i][1]+SamplesIn[0][i+base]); - state->SampleBuffer[offset&mask] = smp * state->FeedGain; + in = temps[i][1] + SamplesIn[0][i+base]; + out = in*state->Filter.b0 + + x[0]*state->Filter.b1 + x[1]*state->Filter.b2 - + y[0]*state->Filter.a1 - y[1]*state->Filter.a2; + x[1] = x[0]; x[0] = in; + y[1] = y[0]; y[0] = out; + + state->SampleBuffer[offset&mask] = out * state->FeedGain; offset++; } @@ -166,6 +176,10 @@ static ALvoid ALechoState_process(ALechoState *state, ALuint SamplesToDo, const base += td; } + state->Filter.x[0] = x[0]; + state->Filter.x[1] = x[1]; + state->Filter.y[0] = y[0]; + state->Filter.y[1] = y[1]; state->Offset = offset; } |