Step mixing gains per-sample for non-HRTF mixing

This fades the dry mixing gains using a logarithmic curve, which should produce
a smoother transition than a linear one. It functions similarly to a linear
fade except that

step = (target - current) / numsteps;
...
gain += step;

becomes

step = powf(target / current, 1.0f / numsteps);
...
gain *= step;

where 'target' and 'current' are clamped to a lower bound that is greater than
0 (which makes no sense on a logarithmic scale).

Consequently, the non-HRTF direct mixers do not do not feed into the click
removal and pending click buffers, as this per-sample fading would do an
adequate job of stopping clicks and pops caused by extreme gain changes. These
buffers should be removed shortly.

1 files changed, 1 insertions, 1 deletions

diff --git a/Alc/mixer_inc.c b/Alc/mixer_inc.c
index 1cb1967d..d27cb979 100644
--- a/Alc/mixer_inc.c
+++ b/Alc/mixer_inc.c
@@ -43,8 +43,8 @@ void MixDirect_Hrtf(DirectParams *params, const ALfloat *restrict data, ALuint s
     const ALuint *restrict TargetDelay = params->Mix.Hrtf.Params.Delay[srcchan];
     ALfloat *restrict History = params->Mix.Hrtf.State.History[srcchan];
     ALfloat (*restrict Values)[2] = params->Mix.Hrtf.State.Values[srcchan];
-    ALuint Offset = params->Mix.Hrtf.State.Offset + OutPos;
     ALint Counter = maxu(params->Counter, OutPos) - OutPos;
+    ALuint Offset = params->Offset + OutPos;
     ALIGN(16) ALfloat Coeffs[HRIR_LENGTH][2];
     ALuint Delay[2];
     ALfloat left, right;