ref: 119a847191fdec2ed1118c5cac0a653e20259aa5
dir: /snd_mix.c/
// snd_mix.c -- portable code to mix sounds for snd_dma.c
#include <u.h>
#include <libc.h>
#include "quakedef.h"
#ifdef _WIN32
#include "winquake.h"
#else
#define DWORD u32int
#endif
#define PAINTBUFFER_SIZE 512
portable_samplepair_t paintbuffer[PAINTBUFFER_SIZE];
int snd_scaletable[32][256];
int *snd_p, snd_linear_count, snd_vol;
short *snd_out;
void Snd_WriteLinearBlastStereo16 (void);
#if !id386
void Snd_WriteLinearBlastStereo16 (void)
{
int i;
int val;
for (i=0 ; i<snd_linear_count ; i+=2)
{
val = (snd_p[i]*snd_vol)>>8;
if (val > 0x7fff)
snd_out[i] = 0x7fff;
else if (val < (short)0x8000)
snd_out[i] = (short)0x8000;
else
snd_out[i] = val;
val = (snd_p[i+1]*snd_vol)>>8;
if (val > 0x7fff)
snd_out[i+1] = 0x7fff;
else if (val < (short)0x8000)
snd_out[i+1] = (short)0x8000;
else
snd_out[i+1] = val;
}
}
#endif
void S_TransferStereo16 (int endtime)
{
int lpos;
int lpaintedtime;
DWORD *pbuf;
#ifdef _WIN32
int reps;
DWORD dwSize,dwSize2;
DWORD *pbuf2;
HRESULT hresult;
#endif
snd_vol = volume.value*256;
snd_p = (int *) paintbuffer;
lpaintedtime = paintedtime;
#ifdef _WIN32
if (pDSBuf)
{
reps = 0;
while ((hresult = pDSBuf->lpVtbl->Lock(pDSBuf, 0, gSndBufSize, &pbuf, &dwSize,
&pbuf2, &dwSize2, 0)) != DS_OK)
{
if (hresult != DSERR_BUFFERLOST)
{
Con_Printf ("S_TransferStereo16: DS::Lock Sound Buffer Failed\n");
S_Shutdown ();
S_Startup ();
return;
}
if (++reps > 10000)
{
Con_Printf ("S_TransferStereo16: DS: couldn't restore buffer\n");
S_Shutdown ();
S_Startup ();
return;
}
}
}
else
#endif
{
pbuf = (DWORD *)shm->buffer;
}
while (lpaintedtime < endtime)
{
// handle recirculating buffer issues
lpos = lpaintedtime & ((shm->samples>>1)-1);
snd_out = (short *) pbuf + (lpos<<1);
snd_linear_count = (shm->samples>>1) - lpos;
if (lpaintedtime + snd_linear_count > endtime)
snd_linear_count = endtime - lpaintedtime;
snd_linear_count <<= 1;
// write a linear blast of samples
Snd_WriteLinearBlastStereo16 ();
snd_p += snd_linear_count;
lpaintedtime += (snd_linear_count>>1);
}
#ifdef _WIN32
if (pDSBuf)
pDSBuf->lpVtbl->Unlock(pDSBuf, pbuf, dwSize, NULL, 0);
#endif
}
void S_TransferPaintBuffer(int endtime)
{
int out_idx;
int count;
int out_mask;
int *p;
int step;
int val;
int snd_vol;
DWORD *pbuf;
#ifdef _WIN32
int reps;
DWORD dwSize,dwSize2;
DWORD *pbuf2;
HRESULT hresult;
#endif
if (shm->samplebits == 16 && shm->channels == 2)
{
S_TransferStereo16 (endtime);
return;
}
p = (int *) paintbuffer;
count = (endtime - paintedtime) * shm->channels;
out_mask = shm->samples - 1;
out_idx = paintedtime * shm->channels & out_mask;
step = 3 - shm->channels;
snd_vol = volume.value*256;
#ifdef _WIN32
if (pDSBuf)
{
reps = 0;
while ((hresult = pDSBuf->lpVtbl->Lock(pDSBuf, 0, gSndBufSize, &pbuf, &dwSize,
&pbuf2,&dwSize2, 0)) != DS_OK)
{
if (hresult != DSERR_BUFFERLOST)
{
Con_Printf ("S_TransferPaintBuffer: DS::Lock Sound Buffer Failed\n");
S_Shutdown ();
S_Startup ();
return;
}
if (++reps > 10000)
{
Con_Printf ("S_TransferPaintBuffer: DS: couldn't restore buffer\n");
S_Shutdown ();
S_Startup ();
return;
}
}
}
else
#endif
{
pbuf = (DWORD *)shm->buffer;
}
if (shm->samplebits == 16)
{
short *out = (short *) pbuf;
while (count--)
{
val = (*p * snd_vol) >> 8;
p+= step;
if (val > 0x7fff)
val = 0x7fff;
else if (val < (short)0x8000)
val = (short)0x8000;
out[out_idx] = val;
out_idx = (out_idx + 1) & out_mask;
}
}
else if (shm->samplebits == 8)
{
unsigned char *out = (unsigned char *) pbuf;
while (count--)
{
val = (*p * snd_vol) >> 8;
p+= step;
if (val > 0x7fff)
val = 0x7fff;
else if (val < (short)0x8000)
val = (short)0x8000;
out[out_idx] = (val>>8) + 128;
out_idx = (out_idx + 1) & out_mask;
}
}
#ifdef _WIN32
if (pDSBuf) {
DWORD dwNewpos, dwWrite;
int il = paintedtime;
int ir = endtime - paintedtime;
ir += il;
pDSBuf->lpVtbl->Unlock(pDSBuf, pbuf, dwSize, NULL, 0);
pDSBuf->lpVtbl->GetCurrentPosition(pDSBuf, &dwNewpos, &dwWrite);
// if ((dwNewpos >= il) && (dwNewpos <= ir))
// Con_Printf("%d-%d p %d c\n", il, ir, dwNewpos);
}
#endif
}
/*
===============================================================================
CHANNEL MIXING
===============================================================================
*/
void SND_PaintChannelFrom8 (channel_t *ch, sfxcache_t *sc, int endtime);
void SND_PaintChannelFrom16 (channel_t *ch, sfxcache_t *sc, int endtime);
void S_PaintChannels(int endtime)
{
int i;
int end;
channel_t *ch;
sfxcache_t *sc;
int ltime, count;
while (paintedtime < endtime)
{
// if paintbuffer is smaller than DMA buffer
end = endtime;
if (endtime - paintedtime > PAINTBUFFER_SIZE)
end = paintedtime + PAINTBUFFER_SIZE;
// clear the paint buffer
Q_memset(paintbuffer, 0, (end - paintedtime) * sizeof(portable_samplepair_t));
// paint in the channels.
ch = channels;
for (i=0; i<total_channels ; i++, ch++)
{
if (!ch->sfx)
continue;
if (!ch->leftvol && !ch->rightvol)
continue;
sc = S_LoadSound (ch->sfx);
if (!sc)
continue;
ltime = paintedtime;
while (ltime < end)
{ // paint up to end
if (ch->end < end)
count = ch->end - ltime;
else
count = end - ltime;
if (count > 0)
{
if (sc->width == 1)
SND_PaintChannelFrom8(ch, sc, count);
else
SND_PaintChannelFrom16(ch, sc, count);
ltime += count;
}
// if at end of loop, restart
if (ltime >= ch->end)
{
if (sc->loopstart >= 0)
{
ch->pos = sc->loopstart;
ch->end = ltime + sc->length - ch->pos;
}
else
{ // channel just stopped
ch->sfx = NULL;
break;
}
}
}
}
// transfer out according to DMA format
S_TransferPaintBuffer(end);
paintedtime = end;
}
}
void SND_InitScaletable (void)
{
int i, j;
for (i=0 ; i<32 ; i++)
for (j=0 ; j<256 ; j++)
snd_scaletable[i][j] = ((signed char)j) * i * 8;
}
#if !id386
void SND_PaintChannelFrom8 (channel_t *ch, sfxcache_t *sc, int count)
{
int data;
int *lscale, *rscale;
unsigned char *sfx;
int i;
if (ch->leftvol > 255)
ch->leftvol = 255;
if (ch->rightvol > 255)
ch->rightvol = 255;
lscale = snd_scaletable[ch->leftvol >> 3];
rscale = snd_scaletable[ch->rightvol >> 3];
sfx = (signed char *)sc->data + ch->pos;
for (i=0 ; i<count ; i++)
{
data = sfx[i];
paintbuffer[i].left += lscale[data];
paintbuffer[i].right += rscale[data];
}
ch->pos += count;
}
#endif // !id386
void SND_PaintChannelFrom16 (channel_t *ch, sfxcache_t *sc, int count)
{
int data;
int left, right;
int leftvol, rightvol;
signed short *sfx;
int i;
leftvol = ch->leftvol;
rightvol = ch->rightvol;
sfx = (signed short *)sc->data + ch->pos;
for (i=0 ; i<count ; i++)
{
data = sfx[i];
left = (data * leftvol) >> 8;
right = (data * rightvol) >> 8;
paintbuffer[i].left += left;
paintbuffer[i].right += right;
}
ch->pos += count;
}