Anton Baskanov : dsound: Preserve freqAccNum value in DSOUND_RecalcFormat().

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 4871cd032f389383798c05178180c0aba8a2c537
URL:    https://gitlab.winehq.org/wine/wine/-/commit/4871cd032f389383798c05178180c0a...

Author: Anton Baskanov <baskanov(a)gmail.com>
Date:   Wed Apr 26 11:59:30 2023 +0700

dsound: Preserve freqAccNum value in DSOUND_RecalcFormat().

Resetting it results in position discontinuity. With frequent
SetFrequency() calls, this produces audible crackling. The issue
affects pedestrian voices in GTA: San Andreas.

---

 dlls/dsound/mixer.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/dlls/dsound/mixer.c b/dlls/dsound/mixer.c
index dbef1bc40fa..4d0c54735cf 100644
--- a/dlls/dsound/mixer.c
+++ b/dlls/dsound/mixer.c
@@ -96,6 +96,7 @@ void DSOUND_RecalcFormat(IDirectSoundBufferImpl *dsb)
 {
 	DWORD ichannels = dsb->pwfx->nChannels;
 	DWORD ochannels = dsb->device->pwfx->nChannels;
+	LONG64 oldFreqAdjustDen = dsb->freqAdjustDen;
 	WAVEFORMATEXTENSIBLE *pwfxe;
 	BOOL ieee = FALSE;
 
@@ -130,7 +131,8 @@ void DSOUND_RecalcFormat(IDirectSoundBufferImpl *dsb)
 	/* calculate the 10ms write lead */
 	dsb->writelead = (dsb->freq / 100) * dsb->pwfx->nBlockAlign;
 
-	dsb->freqAccNum = 0;
+	if (oldFreqAdjustDen)
+		dsb->freqAccNum = (dsb->freqAccNum * dsb->freqAdjustDen + oldFreqAdjustDen / 2) / oldFreqAdjustDen;
 
 	dsb->get_aux = ieee ? getbpp[4] : getbpp[dsb->pwfx->wBitsPerSample/8 - 1];
 	dsb->put_aux = putieee32;