/*

Name: MDRIVER.C

Description:

These routines are used to access the available soundcard drivers.

Portability:

All systems - all compilers

*/

#include "mikmod.h"

MDRIVER *firstdriver = NULL, *md_driver = &drv_nos;

extern UNIMOD *pf; /* <- this modfile is being played */

UWORD md_device = 0;

UWORD md_mixfreq = 44100;

UWORD md_mode = DMODE_STEREO | DMODE_16BITS | DMODE_SURROUND;

UWORD md_dmabufsize = 50;

UBYTE md_pansep = 128; /* 128 == 100% (full left/right) */

UBYTE md_reverb = 6; /* Reverb */

UBYTE md_volume = 96; /* Global sound volume (0-128) */

UBYTE md_musicvolume = 128; /* volume of song */

UBYTE md_sndfxvolume = 128; /* volume of sound effects */

UBYTE md_bpm = 125;

/* Do not modify the numchn variables yourself! use MD_SetVoices() */

UBYTE md_numchn = 0, md_sngchn = 0, md_sfxchn = 0;

UBYTE md_hardchn = 0, md_softchn = 0;

void (*md_player)(void) = Player_HandleTick;

static BOOL isplaying = 0, initialized = 0;

static UBYTE *sfxinfo;

static int sfxpool;

static SAMPLE **md_sample = NULL;

/* Backup variables. This way, the end programmer can fiddle with the */

/* main globals without mikmod blowing up. */

static UWORD idevice, imixfreq, imode, idmabufsize;

static void LimitHardVoices(int limit)

/* Limits the number of hardware voices to the specified amount. */

/* This function should only be used by the low-level drivers. */

{

int t = 0;

if(!(md_mode & DMODE_SOFT_SNDFX) && (md_sfxchn > limit)) md_sfxchn = limit;

if(!(md_mode & DMODE_SOFT_MUSIC) && (md_sngchn > limit)) md_sngchn = limit;

if(!(md_mode & DMODE_SOFT_SNDFX))

md_hardchn = md_sfxchn;

else

md_hardchn = 0;

if(!(md_mode & DMODE_SOFT_MUSIC))

md_hardchn += md_sngchn;

while(md_hardchn > limit)

{

if(++t & 1)

if(!(md_mode & DMODE_SOFT_SNDFX) && (md_sfxchn > 4)) md_sfxchn--;

else

if(!(md_mode & DMODE_SOFT_MUSIC) && (md_sngchn > 8)) md_sngchn--;

if(!(md_mode & DMODE_SOFT_SNDFX))

md_hardchn = md_sfxchn;

else

md_hardchn = 0;

if(!(md_mode & DMODE_SOFT_MUSIC))

md_hardchn += md_sngchn;

}

md_numchn = md_hardchn + md_softchn;

}

static void LimitSoftVoices(int limit)

/* Limits the number of hardware voices to the specified amount. */

/* This function should only be used by the low-level drivers. */

{

int t = 0;

if((md_mode & DMODE_SOFT_SNDFX) && (md_sfxchn > limit)) md_sfxchn = limit;

if((md_mode & DMODE_SOFT_MUSIC) && (md_sngchn > limit)) md_sngchn = limit;

if(md_mode & DMODE_SOFT_SNDFX)

md_softchn = md_sfxchn;

else

md_softchn = 0;

if(md_mode & DMODE_SOFT_MUSIC)

md_softchn += md_sngchn;

while(md_softchn > limit)

{

if(++t & 1)

if((md_mode & DMODE_SOFT_SNDFX) && (md_sfxchn > 4)) md_sfxchn--;

else

if((md_mode & DMODE_SOFT_MUSIC) && (md_sngchn > 8)) md_sngchn--;

if(!(md_mode & DMODE_SOFT_SNDFX))

md_softchn = md_sfxchn;

else

md_softchn = 0;

if(!(md_mode & DMODE_SOFT_MUSIC))

md_softchn += md_sngchn;

}

md_numchn = md_hardchn + md_softchn;

}

/* Note: 'type' indicates whether the returned value should be for music */

/* or for sound effects. */

ULONG MD_SampleSpace(int type)

{

if(type==MD_MUSIC)

type = (md_mode & DMODE_SOFT_MUSIC) ? MD_SOFTWARE : MD_HARDWARE;

else if(type==MD_SNDFX)

type = (md_mode & DMODE_SOFT_SNDFX) ? MD_SOFTWARE : MD_HARDWARE;

return md_driver->FreeSampleSpace(type);

}

ULONG MD_SampleLength(int type, SAMPLE *s)

{

if(type==MD_MUSIC)

type = (md_mode & DMODE_SOFT_MUSIC) ? MD_SOFTWARE : MD_HARDWARE;

else if(type==MD_SNDFX)

type = (md_mode & DMODE_SOFT_SNDFX) ? MD_SOFTWARE : MD_HARDWARE;

return md_driver->RealSampleLength(type, s);

}

UWORD MD_SetDMA(int secs)

/* Converts the given number of 1/10th seconds into the number of bytes of */

/* audio that a sample # 1/10th seconds long would require at the current md_* */

/* settings. */

{

ULONG result;

result = (md_mixfreq * ((md_mode & DMODE_STEREO) ? 2 : 1) *

((md_mode & DMODE_16BITS) ? 2 : 1) * secs) * 10;

if(result > 32000) result = 32000;

return(md_dmabufsize = (result & ~3)); /* round it off to an 8 byte boundry */

}

void MD_InfoDriver(void)

{

int t;

MDRIVER *l;

/* list all registered devicedrivers: */

for(t=1,l=firstdriver; l!=NULL; l=l->next, t++)

printf("%d. %s\n",t,l->Version);

}

void MD_RegisterDriver(MDRIVER *drv)

{

MDRIVER *cruise = firstdriver;

if(cruise!=NULL)

{ while(cruise->next!=NULL) cruise = cruise->next;

cruise->next = drv;

} else

firstdriver = drv;

}

SWORD MD_SampleLoad(SAMPLOAD *s, int type, FILE *fp)

/* type - sample type .. MD_MUSIC or MD_SNDFX */

{

SWORD result;

if(type==MD_MUSIC)

type = (md_mode & DMODE_SOFT_MUSIC) ? MD_SOFTWARE : MD_HARDWARE;

else if(type==MD_SNDFX)

type = (md_mode & DMODE_SOFT_SNDFX) ? MD_SOFTWARE : MD_HARDWARE;

SL_Init(s);

result = md_driver->SampleLoad(s, type);

SL_Exit(s);

return result;

}

void MD_SampleUnLoad(SWORD handle)

{

md_driver->SampleUnLoad(handle);

}

void MD_SetBPM(UBYTE bpm)

{

md_bpm = bpm;

}

void MikMod_RegisterPlayer(void (*player)(void))

{

md_player = player;

}

void MikMod_Update(void)

{

if(isplaying && !(pf->forbid)) md_driver->Update();

}

void Voice_SetVolume(int voice, UWORD vol)

{

ULONG tmp;

if((voice<0) || (voice>=md_numchn)) return;

tmp = (ULONG)vol * (ULONG)md_volume * ((voice < md_sngchn) ? (ULONG)md_musicvolume : (ULONG)md_sndfxvolume);

md_driver->VoiceSetVolume(voice,tmp/16384UL);

}

void Voice_SetFrequency(int voice, ULONG frq)

{

if((voice < 0) || (voice >= md_numchn)) return;

if(md_sample[voice]!=NULL && md_sample[voice]->divfactor!=0) frq/=md_sample[voice]->divfactor;

md_driver->VoiceSetFrequency(voice, frq);

}

void Voice_SetPanning(int voice, ULONG pan)

{

if((voice < 0) || (voice >= md_numchn)) return;

if(pan!=PAN_SURROUND)

{ if(md_mode & DMODE_REVERSE) pan = 255-pan;

pan = (((SWORD)(pan-128)*md_pansep) / 128)+128;

}

md_driver->VoiceSetPanning(voice, pan);

}

void Voice_Play(int voice, SAMPLE *s, ULONG start)

{

ULONG repend;

if((voice < 0) || (voice >= md_numchn) || (start >= s->length)) return;

md_sample[voice] = s;

repend = s->loopend;

if(s->flags&SF_LOOP)

if(repend > s->length) repend = s->length; /* repend can't be bigger than size */

md_driver->VoicePlay(voice,s->handle,start,s->length,s->loopstart,repend,s->flags);

}

void Voice_Stop(int voice)

{

if((voice < 0) || (voice >= md_numchn)) return;

if(voice >= md_sngchn)

{ /* It is a sound effects channel, so flag the voice as non-critical! */

sfxinfo[voice-md_sngchn] = 0;

}

md_driver->VoiceStop(voice);

}

BOOL Voice_Stopped(int voice)

{

if((voice < 0) || (voice >= md_numchn)) return 0;

return(md_driver->VoiceStopped(voice));

}

SLONG Voice_GetPosition(int voice)

{

if((voice < 0) || (voice >= md_numchn)) return 0;

return(md_driver->VoiceGetPosition(voice));

}

ULONG Voice_RealVolume(int voice)

{

if((voice < 0) || (voice >= md_numchn)) return 0;

return(md_driver->VoiceRealVolume(voice));

}

/* ================================ */

/* Functions prefixed with MikMod */

/* ================================ */

BOOL MikMod_Init(void)

{

UWORD t;

_mm_critical = 1;

/* if md_device==0, try to find a device number */

if(md_device==0)

{ for(t=1,md_driver=firstdriver; md_driver!=NULL; md_driver=md_driver->next, t++)

{ if(md_driver->IsPresent()) break;

}

if(md_driver==NULL)

{ _mm_errno = MMERR_DETECTING_DEVICE;

if(_mm_errorhandler!=NULL) _mm_errorhandler();

md_driver = &drv_nos;

return 1;

}

md_device = t;

} else

{ /* if n>0 use that driver */

for(t=1,md_driver=firstdriver; (md_driver!=NULL) && (t!=md_device); md_driver=md_driver->next, t++);

if(md_driver==NULL)

{ _mm_errno = MMERR_INVALID_DEVICE;

if(_mm_errorhandler!=NULL) _mm_errorhandler();

md_driver = &drv_nos;

return 1;

}

if(!md_driver->IsPresent())

{ _mm_errno = MMERR_DETECTING_DEVICE;

if(_mm_errorhandler!=NULL) _mm_errorhandler();

md_driver = &drv_nos;

return 1;

}

}

if(md_driver->Init())

{ MikMod_Exit();

if(_mm_errorhandler!=NULL) _mm_errorhandler();

return 1;

}

idevice = md_device; imode = md_mode;

imixfreq = md_mixfreq; idmabufsize = md_dmabufsize;

initialized = 1;

_mm_critical = 0;

return 0;

}

void MikMod_Exit(void)

{

MikMod_DisableOutput();

md_driver->Exit();

md_numchn = md_sfxchn = md_sngchn = 0;

md_driver = &drv_nos;

initialized = 0;

}

BOOL MikMod_Reset(void)

/* Reset the driver using the new global variable settings. */

/* If the driver has not been initialized, it will be now. */

{

if(!initialized) return MikMod_Init();

if((md_driver->Reset == NULL) || (md_device != idevice))

{ /* md_driver->Reset was NULL, or md_device was changed, */

/* so do a full reset of the driver. */

if(isplaying) md_driver->PlayStop();

md_driver->Exit();

if(MikMod_Init())

{ MikMod_Exit();

if(_mm_errorhandler!=NULL) _mm_errorhandler();

return 1;

}

if(isplaying) md_driver->PlayStart();

} else

{ if(md_driver->Reset())

{ MikMod_Exit();

if(_mm_errorhandler!=NULL) _mm_errorhandler();

return 1;

}

}

return 0;

}

BOOL MikMod_SetNumVoices(int music, int sfx)

/* If either parameter is -1, the current set value will be retained. */

{

BOOL resume = 0;

int t, oldchn = 0;

if((music==0) && (sfx==0)) return 0;

_mm_critical = 1;

if(isplaying)

{ MikMod_DisableOutput();

oldchn = md_numchn;

resume = 1;

}

if(sfxinfo!=NULL) free(sfxinfo);

if(md_sample!=NULL) free(md_sample);

md_sample = NULL;

sfxinfo = NULL;

/*md_softchn = md_hardchn = 0;

if(md_mode & DMODE_SOFT_SNDFX)

md_softchn = sfx; else md_hardchn = sfx;

if(md_mode & DMODE_SOFT_MUSIC)

md_softchn += music; else md_hardchn += music;

*/

if(music != -1) md_sngchn = music;

if(sfx != -1) md_sfxchn = sfx;

md_numchn = md_sngchn + md_sfxchn;

LimitHardVoices(md_driver->HardVoiceLimit);

LimitSoftVoices(md_driver->SoftVoiceLimit);

if(md_driver->SetNumVoices())

{ MikMod_Exit();

md_numchn = md_softchn = md_hardchn = md_sfxchn = md_sngchn = 0;

if(_mm_errorhandler!=NULL) _mm_errorhandler();

return 1;

}

if(md_sngchn || md_sfxchn)

md_sample = (SAMPLE **)_mm_calloc(md_sngchn+md_sfxchn, sizeof(SAMPLE *));

if(md_sfxchn)

sfxinfo = (UBYTE *)_mm_calloc(md_sfxchn, sizeof(UBYTE));

/* make sure the player doesn't start with garbage */

for(t=oldchn; t<md_numchn; t++) Voice_Stop(t);

sfxpool = 0;

if(resume) MikMod_EnableOutput();

_mm_critical = 0;

return 0;

}

BOOL MikMod_EnableOutput(void)

{

/* safety valve, prevents entering */

/* playstart twice: */

_mm_critical = 1;

if(!isplaying)

{ if(md_driver->PlayStart()) return 1;

isplaying = 1;

}

_mm_critical = 0;

return 0;

}

void MikMod_DisableOutput(void)

{

/* safety valve, prevents calling playStop when playstart */

/* hasn't been called: */

if(isplaying && md_driver!=NULL)

{ isplaying = 0;

md_driver->PlayStop();

}

}

BOOL MikMod_Active(void)

{

return isplaying;

}

int MikMod_PlaySample(SAMPLE *s, ULONG start, UBYTE flags)

/* Plays a sound effects sample. Picks a voice from the number of voices */

/* allocated for use as sound effects (loops through voices, skipping all */

/* active criticals). */

/* */

/* Returns the voice that the sound is being played on. */

{

int orig = sfxpool; /* for cases where all channels are critical */

int c;

if(md_sfxchn==0) return -1;

if(s->volume > 64) s->volume = 64;

/* check the first location after sfxpool */

do

{ if(sfxinfo[sfxpool] & SFX_CRITICAL)

{ if(md_driver->VoiceStopped(c=sfxpool+md_sngchn))

{ sfxinfo[sfxpool] = flags;

Voice_Play(c, s, start);

md_driver->VoiceSetVolume(c,s->volume<<2);

md_driver->VoiceSetPanning(c,s->panning);

md_driver->VoiceSetFrequency(c,s->speed);

sfxpool++;

if(sfxpool >= md_sfxchn) sfxpool = 0;

return c;

}

} else

{ sfxinfo[sfxpool] = flags;

Voice_Play(c=sfxpool+md_sngchn, s, start);

md_driver->VoiceSetVolume(c,s->volume<<2);

md_driver->VoiceSetPanning(c,s->panning);

md_driver->VoiceSetFrequency(c,s->speed);

sfxpool++;

if(sfxpool >= md_sfxchn) sfxpool = 0;

return c;

}

sfxpool++;

if(sfxpool >= md_sfxchn) sfxpool = 0;

} while(sfxpool!=orig);

return -1;

}