ref: 421b13439f877ca1b3d9a13c07df10bf16928897
dir: /i_sound.c/
//**************************************************************************
//**
//** i_soundpi.c: unix sound driver using a plugin interface
//**
//** $Revision: 512 $
//** $Date: 2009-06-04 18:00:34 +0300 (Thu, 04 Jun 2009) $
//**
//**************************************************************************
#include "h2stdinc.h"
#include "h2def.h"
#include "sounds.h"
#include "i_sound.h"
#include "audio_plugin.h"
#define SAMPLE_ZERO 0
#define SAMPLE_RATE 11025 /* Hz */
#define SAMPLE_CHANNELS 2
#define TARGET_RATE 44100
#define SAMPLE_TYPE short
/*
* SOUND HEADER & DATA
*/
int snd_Channels;
int snd_MaxVolume, /* maximum volume for sound */
snd_MusicVolume; /* maximum volume for music */
boolean snd_MusicAvail, /* whether music is available */
snd_SfxAvail; /* whether sfx are available */
/*
* SOUND FX API
*/
typedef struct
{
unsigned char *begin; /* pointers into Sample.firstSample */
unsigned char *end;
SAMPLE_TYPE *lvol_table; /* point into vol_lookup */
SAMPLE_TYPE *rvol_table;
unsigned int pitch_step;
unsigned int step_remainder; /* 0.16 bit remainder of last step. */
int pri;
unsigned int time;
} Channel;
#pragma pack on
typedef struct
{
/* Sample data is a lump from a wad: byteswap the a, freq
* and the length fields before using them */
short a; /* always 3 */
short freq; /* always 11025 */
int32_t length; /* sample length */
unsigned char firstSample;
} Sample;
#pragma pack off
static int audio_exit_thread = 1;
//static pthread_t audio_thread;
#define CHAN_COUNT 8
static Channel channel[CHAN_COUNT];
#define MAX_VOL 64 /* 64 keeps our table down to 16Kb */
static SAMPLE_TYPE vol_lookup[MAX_VOL * 256];
static int steptable[256]; /* Pitch to stepping lookup */
#define BUF_LEN (256 * 2 * 4)
static int audiofd;
static QLock audiolk;
boolean mus_paused = false;
static int mpfd[2] = {-1, -1};
static void audioproc(void)
{
Channel* chan;
Channel* cend;
char buf[BUF_LEN];
SAMPLE_TYPE *begin;
SAMPLE_TYPE *end;
unsigned int sample;
register int dl, ml;
register int dr, mr;
int i;
end = (SAMPLE_TYPE *) (buf + BUF_LEN);
cend = channel + CHAN_COUNT;
procsetname("hexen audioproc");
for(;;){
memset(buf, 0, sizeof buf);
if(mpfd[0]>=0 && !mus_paused && readn(mpfd[0], buf, sizeof buf) < 0){
fprint(2, "I_UpdateSound: disabling music: %r\n");
I_ShutdownMusic();
}
begin = (SAMPLE_TYPE *) buf;
while (begin < end){
// Mix all the channels together.
dl = SAMPLE_ZERO;
dr = SAMPLE_ZERO;
qlock(&audiolk);
chan = channel;
for ( ; chan < cend; chan++){
if(!chan->begin)
continue;
// Get the sample from the channel.
sample = *chan->begin;
// Adjust volume accordingly.
dl += chan->lvol_table[sample];
dr += chan->rvol_table[sample];
// Increment sample pointer with pitch adjustment.
chan->step_remainder += chan->pitch_step;
chan->begin += chan->step_remainder >> 16;
chan->step_remainder &= 65535;
// Check whether we are done.
if (chan->begin >= chan->end)
{
chan->begin = NULL;
//printf (" channel done %d\n", chan);
}
}
qunlock(&audiolk);
for(i=0; i < TARGET_RATE/SAMPLE_RATE; i++){
ml = dl + *begin;
if (ml > 0x7fff)
ml = 0x7fff;
else if (ml < -0x8000)
ml = -0x8000;
*begin++ = ml;
mr = dr + *begin;
if (mr > 0x7fff)
mr = 0x7fff;
else if (mr < -0x8000)
mr = -0x8000;
*begin++ = mr;
}
}
write(audiofd, buf, BUF_LEN);
}
}
void I_SetSfxVolume(int volume)
{
USED(volume);
}
// Gets lump nums of the named sound. Returns pointer which will be
// passed to I_StartSound() when you want to start an SFX. Must be
// sure to pass this to UngetSoundEffect() so that they can be
// freed!
int I_GetSfxLumpNum(sfxinfo_t *sound)
{
return W_GetNumForName(sound->lumpname);
}
// Id is unused.
// Data is a pointer to a Sample structure.
// Volume ranges from 0 to 127.
// Separation (orientation/stereo) ranges from 0 to 255. 128 is balanced.
// Pitch ranges from 0 to 255. Normal is 128.
// Priority looks to be unused (always 0).
int I_StartSound(int id, void *data, int vol, int sep, int pitch, int priority)
{
// Relative time order to find oldest sound.
static unsigned int soundTime = 0;
int chanId;
Sample *sample;
Channel *chan;
int oldest;
int i;
USED(id);
// Find an empty channel, the oldest playing channel, or default to 0.
// Currently ignoring priority.
chanId = 0;
oldest = soundTime;
for (i = 0; i < CHAN_COUNT; i++)
{
if (! channel[ i ].begin)
{
chanId = i;
break;
}
if (channel[ i ].time < oldest)
{
chanId = i;
oldest = channel[ i ].time;
}
}
sample = (Sample *) data;
chan = &channel[chanId];
I_UpdateSoundParams(chanId + 1, vol, sep, pitch);
// begin must be set last because the audio thread will access the channel
// once it is non-zero. Perhaps this should be protected by a mutex.
chan->pri = priority;
chan->time = soundTime;
chan->end = &sample->firstSample + LONG(sample->length);
chan->begin = &sample->firstSample;
soundTime++;
#if 0
printf ("I_StartSound %d: v:%d s:%d p:%d pri:%d | %d %d %d %d\n",
id, vol, sep, pitch, priority,
chanId, chan->pitch_step, SHORT(sample->a), SHORT(sample->freq));
#endif
return chanId + 1;
}
void I_StopSound(int handle)
{
handle--;
handle &= 7;
channel[handle].begin = NULL;
}
int I_SoundIsPlaying(int handle)
{
handle--;
handle &= 7;
return (channel[ handle ].begin != NULL);
}
void I_UpdateSoundParams(int handle, int vol, int sep, int pitch)
{
int lvol, rvol;
Channel *chan;
qlock(&audiolk);
// Set left/right channel volume based on seperation.
sep += 1; // range 1 - 256
lvol = vol - ((vol * sep * sep) >> 16); // (256*256);
sep = sep - 257;
rvol = vol - ((vol * sep * sep) >> 16);
// Sanity check, clamp volume.
if (rvol < 0)
{
// printf ("rvol out of bounds %d, id %d\n", rvol, handle);
rvol = 0;
}
else if (rvol > 127)
{
// printf ("rvol out of bounds %d, id %d\n", rvol, handle);
rvol = 127;
}
if (lvol < 0)
{
// printf ("lvol out of bounds %d, id %d\n", lvol, handle);
lvol = 0;
}
else if (lvol > 127)
{
// printf ("lvol out of bounds %d, id %d\n", lvol, handle);
lvol = 127;
}
// Limit to MAX_VOL (64)
lvol >>= 1;
rvol >>= 1;
handle--;
handle &= 7;
chan = &channel[handle];
chan->pitch_step = steptable[pitch];
chan->step_remainder = 0;
chan->lvol_table = &vol_lookup[lvol * 256];
chan->rvol_table = &vol_lookup[rvol * 256];
qunlock(&audiolk);
}
/*
* SOUND STARTUP STUFF
*/
// inits all sound stuff
void I_StartupSound (void)
{
snd_SfxAvail = false;
if (M_CheckParm("--nosound") || M_CheckParm("-s") || M_CheckParm("-nosound"))
{
ST_Message("I_StartupSound: Sound Disabled.\n");
return;
}
audiofd = open("/dev/audio", OWRITE);
if(audiofd < 0){
ST_Message("I_StartupSound: /dev/audio could not be opened\n");
return;
}
snd_SfxAvail = true;
if(rfork(RFPROC|RFMEM) == 0){
audioproc();
exits(nil);
}
}
// shuts down all sound stuff
void I_ShutdownSound (void)
{
snd_SfxAvail = false;
I_ShutdownMusic();
}
void I_SetChannels(int channels)
{
int v, j;
int *steptablemid;
// We always have CHAN_COUNT channels.
USED(channels);
for (j = 0; j < CHAN_COUNT; j++)
{
channel[j].begin = NULL;
channel[j].end = NULL;
channel[j].time = 0;
}
// This table provides step widths for pitch parameters.
steptablemid = steptable + 128;
for (j = -128; j < 128; j++)
{
steptablemid[j] = (int) (pow(2.0, (j/64.0)) * 65536.0);
}
// Generate the volume lookup tables.
for (v = 0; v < MAX_VOL; v++)
{
for (j = 0; j < 256; j++)
{
// vol_lookup[v*256+j] = 128 + ((v * (j-128)) / (MAX_VOL-1));
// Turn the unsigned samples into signed samples.
vol_lookup[v*256+j] = (v * (j-128) * 256) / (MAX_VOL-1);
// printf ("vol_lookup[%d*256+%d] = %d\n", v, j, vol_lookup[v*256+j]);
}
}
}
/*
* SONG API
*/
static int didgen = 0;
static void genmidi(void)
{
int fd, n, sz;
char name[64];
uchar *gm;
n = W_GetNumForName("GENMIDI");
sz = W_LumpLength(n);
gm = (uchar *)W_CacheLumpNum(n, PU_STATIC);
snprint(name, sizeof(name), "/tmp/genmidi.%d", getpid());
if((fd = create(name, ORDWR|ORCLOSE, 0666)) < 0)
sysfatal("create: %r");
if(write(fd, gm, sz) != sz)
sysfatal("write: %r");
Z_Free(gm);
}
void I_ShutdownMusic(void)
{
if(mpfd[0] >= 0){
close(mpfd[0]);
mpfd[0] = -1;
waitpid();
}
}
/* In theory this allows register step allows
* the use of external files in place of internal ones. */
static void *currentsong = nil;
static int currentsize = 0;
int I_RegisterSong(void *data, int siz)
{
if(!didgen){
genmidi();
didgen++;
}
if(currentsong != nil)
return 0;
currentsong = data;
currentsize = siz;
return 1;
}
int I_RegisterExternalSong(const char *nm)
{
USED(nm);
return 0;
}
void I_UnRegisterSong(int handle)
{
USED(handle);
currentsong = nil;
}
void I_PauseSong(int handle)
{
if(handle <= 0)
return;
mus_paused = true;
}
void I_ResumeSong(int handle)
{
if(handle <= 0)
return;
mus_paused = false;
}
void I_SetMusicVolume(int volume)
{
USED(volume);
}
int I_QrySongPlaying(int handle)
{
USED(handle);
return 0;
}
// Stops a song. MUST be called before I_UnregisterSong().
void I_StopSong(int handle)
{
if(handle <= 0)
return;
I_ShutdownMusic();
}
void I_PlaySong(int handle, boolean loop)
{
char name[64];
int n;
if(M_CheckParm("-nomusic") || audiofd < 0 || handle <= 0)
return;
I_ShutdownMusic();
if(pipe(mpfd) < 0)
return;
switch(rfork(RFPROC|RFFDG|RFNAMEG)){
case -1:
fprint(2, "I_PlaySong: %r\n");
break;
case 0:
dup(mpfd[1], 1);
for(n=3; n<20; n++) close(n);
close(0);
snprint(name, sizeof(name), "/tmp/hexen.%d", getpid());
if(create(name, ORDWR|ORCLOSE, 0666) != 0)
sysfatal("create: %r");
if(write(0, currentsong, currentsize) != currentsize)
sysfatal("write: %r");
if(seek(0, 0, 0) != 0)
sysfatal("seek: %r");
if(bind("/fd/1", "/dev/audio", MREPL) == -1)
sysfatal("bind: %r");
while(loop && fork() > 0){
if(waitpid() < 0 || write(1, "", 0) < 0)
exits(nil);
}
execl("/bin/dmus", "dmus", name, nil);
execl("/bin/play", "play", name, nil);
sysfatal("execl: %r");
default:
close(mpfd[1]);
}
}