/*
Copyright (C) 1996-1997 Id Software, Inc.

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

*/
// snd_dma.c -- main control for any streaming sound output device

#include "quakedef.h"

#ifdef USE_DSOUND
#include <windows.h>
#include <dsound.h>
extern DWORD gSndBufSize;
extern LPDIRECTSOUND pDS;
extern LPDIRECTSOUNDBUFFER pDSBuf;
#endif

#include "snd_ogg.h"


void S_Play(void);
void S_PlayVol(void);
void S_Play2(void);
void S_SoundList(void);
void S_Update_();
void S_StopAllSounds(qboolean clear);
void S_StopAllSoundsC(void);

void S_ClearBuffer (void);


// =======================================================================
// Internal sound data & structures
// =======================================================================

channel_t channels[MAX_CHANNELS];
unsigned int total_channels;

int snd_blocked = 0;
cvar_t snd_initialized = { CVAR_READONLY, "snd_initialized", "0"};
cvar_t snd_streaming = { CVAR_SAVE, "snd_streaming", "1"};

// pointer should go away
volatile dma_t *shm = 0;
volatile dma_t sn;

vec3_t listener_origin;
matrix4x4_t listener_matrix;
vec_t sound_nominal_clip_dist=1000.0;
mempool_t *snd_mempool;

// sample PAIRS
int soundtime;
int paintedtime;


//LordHavoc: increased the client sound limit from 512 to 4096 for the Nehahra movie
#define MAX_SFX 4096
sfx_t *known_sfx; // allocated [MAX_SFX]
int num_sfx;

sfx_t *ambient_sfx[NUM_AMBIENTS];

int sound_started = 0;

cvar_t bgmvolume = {CVAR_SAVE, "bgmvolume", "1"};
cvar_t volume = {CVAR_SAVE, "volume", "0.7"};
cvar_t snd_staticvolume = {CVAR_SAVE, "snd_staticvolume", "1"};

cvar_t nosound = {0, "nosound", "0"};
cvar_t snd_precache = {0, "snd_precache", "1"};
cvar_t bgmbuffer = {0, "bgmbuffer", "4096"};
cvar_t ambient_level = {0, "ambient_level", "0.3"};
cvar_t ambient_fade = {0, "ambient_fade", "100"};
cvar_t snd_noextraupdate = {0, "snd_noextraupdate", "0"};
cvar_t snd_show = {0, "snd_show", "0"};
cvar_t _snd_mixahead = {CVAR_SAVE, "_snd_mixahead", "0.1"};
cvar_t snd_swapstereo = {CVAR_SAVE, "snd_swapstereo", "0"};


// ====================================================================
// User-setable variables
// ====================================================================


//
// Fake dma is a synchronous faking of the DMA progress used for
// isolating performance in the renderer.  The fakedma_updates is
// number of times S_Update() is called per second.
//

qboolean fakedma = false;
int fakedma_updates = 15;


void S_SoundInfo_f(void)
{
	if (!sound_started || !shm)
	{
		Con_Print("sound system not started\n");
		return;
	}

	Con_Printf("%5d stereo\n", shm->format.channels - 1);
	Con_Printf("%5d samples\n", shm->samples);
	Con_Printf("%5d samplepos\n", shm->samplepos);
	Con_Printf("%5d samplebits\n", shm->format.width * 8);
	Con_Printf("%5d speed\n", shm->format.speed);
	Con_Printf("%p dma buffer\n", shm->buffer);
	Con_Printf("%5u total_channels\n", total_channels);
}

void S_UnloadSounds(void)
{
	int i;
	for (i = 0;i < num_sfx;i++)
		S_UnloadSound(known_sfx + i);
}

void S_LoadSounds(void)
{
	int i;
	for (i = 0;i < num_sfx;i++)
		S_LoadSound(known_sfx + i, false);
}

void S_Startup(void)
{
	if (!snd_initialized.integer)
		return;

	shm = &sn;
	memset((void *)shm, 0, sizeof(*shm));

// create a piece of DMA memory

	if (fakedma)
	{
		shm->format.width = 2;
		shm->format.speed = 22050;
		shm->format.channels = 2;
		shm->samples = 32768;
		shm->samplepos = 0;
		shm->buffer = Mem_Alloc(snd_mempool, shm->format.channels * shm->samples * shm->format.width);
	}
	else
	{
		if (!SNDDMA_Init())
		{
			Con_Print("S_Startup: SNDDMA_Init failed.\n");
			sound_started = 0;
			shm = NULL;
			return;
		}
	}

	sound_started = 1;

	Con_DPrintf("Sound sampling rate: %i\n", shm->format.speed);

	//S_LoadSounds();

	S_StopAllSounds(true);
}

void S_Shutdown(void)
{
	if (!sound_started)
		return;

	//S_UnloadSounds();

	if (fakedma)
		Mem_Free(shm->buffer);
	else
		SNDDMA_Shutdown();

	shm = NULL;
	sound_started = 0;
}

void S_Restart_f(void)
{
	S_Shutdown();
	S_Startup();
}

/*
================
S_Init
================
*/
void S_Init(void)
{
	Con_DPrint("\nSound Initialization\n");

	Cvar_RegisterVariable(&volume);
	Cvar_RegisterVariable(&bgmvolume);
	Cvar_RegisterVariable(&snd_staticvolume);

// COMMANDLINEOPTION: -nosound disables sound (including CD audio)
	if (COM_CheckParm("-nosound") || COM_CheckParm("-safe"))
		return;

	snd_mempool = Mem_AllocPool("sound", 0, NULL);

// COMMANDLINEOPTION: -simsound runs sound mixing but with no output
	if (COM_CheckParm("-simsound"))
		fakedma = true;

	Cmd_AddCommand("play", S_Play);
	Cmd_AddCommand("play2", S_Play2);
	Cmd_AddCommand("playvol", S_PlayVol);
	Cmd_AddCommand("stopsound", S_StopAllSoundsC);
	Cmd_AddCommand("soundlist", S_SoundList);
	Cmd_AddCommand("soundinfo", S_SoundInfo_f);
	Cmd_AddCommand("snd_restart", S_Restart_f);

	Cvar_RegisterVariable(&nosound);
	Cvar_RegisterVariable(&snd_precache);
	Cvar_RegisterVariable(&snd_initialized);
	Cvar_RegisterVariable(&snd_streaming);
	Cvar_RegisterVariable(&bgmbuffer);
	Cvar_RegisterVariable(&ambient_level);
	Cvar_RegisterVariable(&ambient_fade);
	Cvar_RegisterVariable(&snd_noextraupdate);
	Cvar_RegisterVariable(&snd_show);
	Cvar_RegisterVariable(&_snd_mixahead);
	Cvar_RegisterVariable(&snd_swapstereo); // LordHavoc: for people with backwards sound wiring

	Cvar_SetValueQuick(&snd_initialized, true);

	known_sfx = Mem_Alloc(snd_mempool, MAX_SFX*sizeof(sfx_t));
	num_sfx = 0;

	SND_InitScaletable ();

	ambient_sfx[AMBIENT_WATER] = S_PrecacheSound ("ambience/water1.wav", false, true);
	ambient_sfx[AMBIENT_SKY] = S_PrecacheSound ("ambience/wind2.wav", false, true);

	total_channels = MAX_DYNAMIC_CHANNELS + NUM_AMBIENTS;	// no statics
	memset(channels, 0, MAX_CHANNELS * sizeof(channel_t));

	OGG_OpenLibrary ();
}


// =======================================================================
// Load a sound
// =======================================================================

/*
=========
S_GetCached

=========
*/
sfx_t *S_GetCached (const char *name, qboolean stdpath)
{
	char namebuffer [MAX_QPATH];
	size_t len;
	int i;

	if (!snd_initialized.integer)
		return NULL;

	if (!name)
		Host_Error("S_GetCached: NULL");

	// Add the default sound directory to the path
	len = snprintf (namebuffer, sizeof (namebuffer), stdpath ? "sound/%s" : "%s", name);
	if (len >= sizeof (namebuffer))
		Host_Error ("S_GetCached: sound name too long (%s)", name);

	for(i = 0;i < num_sfx;i++)
		if(!strcmp(known_sfx[i].name, namebuffer))
			return &known_sfx[i];

	return NULL;
}

/*
==================
S_FindName

==================
*/
sfx_t *S_FindName (const char *name, qboolean stdpath)
{
	sfx_t *sfx;

	if (!snd_initialized.integer)
		return NULL;

	sfx = S_GetCached (name, stdpath);

	// If we haven't allocated a sfx_t struct for it yet
	if (sfx == NULL)
	{
		if (num_sfx == MAX_SFX)
			Sys_Error ("S_FindName: out of sfx_t");

		sfx = &known_sfx[num_sfx++];
		memset (sfx, 0, sizeof(*sfx));
		snprintf (sfx->name, sizeof (sfx->name), stdpath ? "sound/%s" : "%s", name);
	}
	return sfx;
}


/*
==================
S_TouchSound

==================
*/
void S_TouchSound (const char *name, qboolean stdpath)
{
	sfx_t *sfx;

	sfx = S_FindName (name, stdpath);

	// Set the "used" flag for this sound
	if (sfx != NULL)
		sfx->flags |= SFXFLAG_USED;
}


/*
==================
S_ClearUsed

Reset the "used" flag of all precached sounds
==================
*/
void S_ClearUsed (void)
{
	int i;

	for (i = 0; i < num_sfx; i++)
		known_sfx[i].flags &= ~SFXFLAG_USED;
}


/*
==================
S_PurgeUnused

Free all precached sounds without the "used" flag
==================
*/
void S_PurgeUnused (void)
{
	int i;
	sfx_t *sfx;

	for (i = 0; i < num_sfx; i++)
	{
		sfx = &known_sfx[i];
		if (! (sfx->flags & SFXFLAG_USED))
			S_UnloadSound (sfx);
	}
}


/*
==================
S_PrecacheSound

==================
*/
sfx_t *S_PrecacheSound (const char *name, qboolean complain, qboolean stdpath)
{
	sfx_t *sfx;

	if (!snd_initialized.integer)
		return NULL;

	sfx = S_FindName (name, stdpath);

	if (!nosound.integer && snd_precache.integer)
		S_LoadSound(sfx, complain);

	return sfx;
}


//=============================================================================

/*
=================
SND_PickChannel

Picks a channel based on priorities, empty slots, number of channels
=================
*/
channel_t *SND_PickChannel(int entnum, int entchannel)
{
	int ch_idx;
	int first_to_die;
	int life_left;
	channel_t* ch;

// Check for replacement sound, or find the best one to replace
	first_to_die = -1;
	life_left = 0x7fffffff;
	for (ch_idx=NUM_AMBIENTS ; ch_idx < NUM_AMBIENTS + MAX_DYNAMIC_CHANNELS ; ch_idx++)
	{
		ch = &channels[ch_idx];
		if (entchannel != 0		// channel 0 never overrides
		&& ch->entnum == entnum
		&& (ch->entchannel == entchannel || entchannel == -1) )
		{	// always override sound from same entity
			first_to_die = ch_idx;
			break;
		}

		// don't let monster sounds override player sounds
		if (ch->entnum == cl.viewentity && entnum != cl.viewentity && ch->sfx)
			continue;

		// don't override looped sounds
		if ((ch->flags & CHANNELFLAG_FORCELOOP) != 0 ||
			(ch->sfx != NULL && ch->sfx->loopstart >= 0))
			continue;

		if (ch->end - paintedtime < life_left)
		{
			life_left = ch->end - paintedtime;
			first_to_die = ch_idx;
		}
	}

	if (first_to_die == -1)
		return NULL;

	if (channels[first_to_die].sfx)
		channels[first_to_die].sfx = NULL;

	return &channels[first_to_die];
}

/*
=================
SND_Spatialize

Spatializes a channel
=================
*/
void SND_Spatialize(channel_t *ch, int isstatic)
{
	vec_t dist, scale, pan;
	vec3_t source_vec;

	// anything coming from the view entity will always be full volume
	// LordHavoc: make sounds with ATTN_NONE have no spatialization
	if (ch->entnum == cl.viewentity || ch->dist_mult == 0)
	{
		ch->leftvol = ch->master_vol;
		ch->rightvol = ch->master_vol;
	}
	else
	{
		// update sound origin if we know about the entity
		if (ch->entnum > 0 && cls.state == ca_connected && cl_entities[ch->entnum].state_current.active)
		{
			//Con_Printf("-- entnum %i origin %f %f %f neworigin %f %f %f\n", ch->entnum, ch->origin[0], ch->origin[1], ch->origin[2], cl_entities[ch->entnum].state_current.origin[0], cl_entities[ch->entnum].state_current.origin[1], cl_entities[ch->entnum].state_current.origin[2]);
			VectorCopy(cl_entities[ch->entnum].state_current.origin, ch->origin);
			if (cl_entities[ch->entnum].state_current.modelindex && cl.model_precache[cl_entities[ch->entnum].state_current.modelindex]->soundfromcenter)
				VectorMAMAM(1.0f, ch->origin, 0.5f, cl.model_precache[cl_entities[ch->entnum].state_current.modelindex]->normalmins, 0.5f, cl.model_precache[cl_entities[ch->entnum].state_current.modelindex]->normalmaxs, ch->origin);
		}

		// calculate stereo seperation and distance attenuation
		Matrix4x4_Transform(&listener_matrix, ch->origin, source_vec);
		dist = VectorNormalizeLength(source_vec);
		// distance
		scale = ch->master_vol * (1.0 - (dist * ch->dist_mult));
		// panning
		pan = scale * source_vec[1];
		// calculate the volumes
		ch->leftvol = (int) (scale + pan);
		ch->rightvol = (int) (scale - pan);
	}

	// LordHavoc: allow adjusting volume of static sounds
	if (isstatic)
	{
		ch->leftvol *= snd_staticvolume.value;
		ch->rightvol *= snd_staticvolume.value;
	}

	// clamp volumes
	ch->leftvol = bound(0, ch->leftvol, 255);
	ch->rightvol = bound(0, ch->rightvol, 255);
}


// =======================================================================
// Start a sound effect
// =======================================================================

int S_StartSound(int entnum, int entchannel, sfx_t *sfx, vec3_t origin, float fvol, float attenuation)
{
	channel_t *target_chan, *check;
	int		vol;
	int		ch_idx;
	size_t	skip;

	if (!sound_started || !sfx || !sfx->fetcher || nosound.integer)
		return -1;

	vol = fvol*255;

// pick a channel to play on
	target_chan = SND_PickChannel(entnum, entchannel);
	if (!target_chan)
		return -1;

// spatialize
	memset (target_chan, 0, sizeof(*target_chan));
	VectorCopy(origin, target_chan->origin);
	target_chan->dist_mult = attenuation / sound_nominal_clip_dist;
	target_chan->master_vol = vol;
	target_chan->entnum = entnum;
	target_chan->entchannel = entchannel;
	SND_Spatialize(target_chan, false);

	// LordHavoc: spawn the sound anyway because the player might teleport to it
	//if (!target_chan->leftvol && !target_chan->rightvol)
	//	return;		// not audible at all

	// new channel
	if (!S_LoadSound (sfx, true))
	{
		target_chan->sfx = NULL;
		return -1;		// couldn't load the sound's data
	}

	target_chan->sfx = sfx;
	target_chan->flags = CHANNELFLAG_NONE;
	target_chan->pos = 0.0;
	target_chan->end = paintedtime + sfx->total_length;
	target_chan->lastptime = paintedtime;

// if an identical sound has also been started this frame, offset the pos
// a bit to keep it from just making the first one louder
	check = &channels[NUM_AMBIENTS];
	for (ch_idx=NUM_AMBIENTS ; ch_idx < NUM_AMBIENTS + MAX_DYNAMIC_CHANNELS ; ch_idx++, check++)
	{
		if (check == target_chan)
			continue;
		if (check->sfx == sfx && !check->pos)
		{
			// LordHavoc: fixed skip calculations
			skip = 0.1 * sfx->format.speed;
			if (skip > sfx->total_length)
				skip = sfx->total_length;
			if (skip > 0)
				skip = rand() % skip;
			target_chan->pos += skip;
			target_chan->end -= skip;
			break;
		}
	}

	return (target_chan - channels);
}

void S_StopChannel (unsigned int channel_ind)
{
	channel_t *ch;

	if (channel_ind >= total_channels)
		return;

	ch = &channels[channel_ind];
	if (ch->sfx != NULL)
	{
		if (ch->sfx->fetcher != NULL)
		{
			snd_fetcher_end_t fetcher_end = ch->sfx->fetcher->end;
			if (fetcher_end != NULL)
				fetcher_end (ch);
		}
		ch->sfx = NULL;
	}
	ch->end = 0;
}

void S_PauseChannel (unsigned int channel_ind, qboolean toggle)
{
	if (toggle)
		channels[channel_ind].flags |= CHANNELFLAG_PAUSED;
	else
		channels[channel_ind].flags &= ~CHANNELFLAG_PAUSED;
}

void S_LoopChannel (unsigned int channel_ind, qboolean toggle)
{
	if (toggle)
		channels[channel_ind].flags |= CHANNELFLAG_FORCELOOP;
	else
		channels[channel_ind].flags &= ~CHANNELFLAG_FORCELOOP;
}

void S_StopSound(int entnum, int entchannel)
{
	unsigned int i;

	for (i = 0; i < MAX_DYNAMIC_CHANNELS; i++)
		if (channels[i].entnum == entnum && channels[i].entchannel == entchannel)
		{
			S_StopChannel (i);
			return;
		}
}

void S_StopAllSounds(qboolean clear)
{
	unsigned int i;

	for (i = 0; i < total_channels; i++)
		S_StopChannel (i);

	total_channels = MAX_DYNAMIC_CHANNELS + NUM_AMBIENTS;	// no statics
	memset(channels, 0, MAX_CHANNELS * sizeof(channel_t));

	if (clear)
		S_ClearBuffer();
}

void S_StopAllSoundsC(void)
{
	S_StopAllSounds(true);
}

void S_PauseGameSounds (void)
{
	unsigned int i;

	for (i = 0; i < total_channels; i++)
	{
		channel_t *ch;

		ch = &channels[i];
		if (ch->sfx != NULL && ! (ch->flags & CHANNELFLAG_LOCALSOUND))
			ch->flags |= CHANNELFLAG_PAUSED;
	}
}

void S_ResumeGameSounds (void)
{
	unsigned int i;

	for (i = 0; i < total_channels; i++)
	{
		channel_t *ch;

		ch = &channels[i];
		if (ch->sfx != NULL && ! (ch->flags & CHANNELFLAG_LOCALSOUND))
			ch->flags &= ~CHANNELFLAG_PAUSED;
	}
}

void S_SetChannelVolume (unsigned int ch_ind, float fvol)
{
	channels[ch_ind].master_vol = fvol * 255;
}


void S_ClearBuffer(void)
{
	int		clear;

	if (!sound_started || !shm)
		return;

	if (shm->format.width == 1)
		clear = 0x80;
	else
		clear = 0;

#ifdef USE_DSOUND
	if (pDSBuf)
	{
		DWORD	dwSize;
		DWORD	*pData;
		int		reps;
		HRESULT	hresult;

		reps = 0;

		while ((hresult = pDSBuf->lpVtbl->Lock(pDSBuf, 0, gSndBufSize, (LPVOID*)&pData, &dwSize, NULL, NULL, 0)) != DS_OK)
		{
			if (hresult != DSERR_BUFFERLOST)
			{
				Con_Print("S_ClearBuffer: DS::Lock Sound Buffer Failed\n");
				S_Shutdown ();
				return;
			}

			if (++reps > 10000)
			{
				Con_Print("S_ClearBuffer: DS: couldn't restore buffer\n");
				S_Shutdown ();
				return;
			}
		}

		memset(pData, clear, shm->samples * shm->format.width);

		pDSBuf->lpVtbl->Unlock(pDSBuf, pData, dwSize, NULL, 0);

	}
	else
#endif
	if (shm->buffer)
	{
		int		setsize = shm->samples * shm->format.width;
		char	*buf = shm->buffer;

		while (setsize--)
			*buf++ = clear;

// on i586/i686 optimized versions of glibc, glibc *wrongly* IMO,
// reads the memory area before writing to it causing a seg fault
// since the memory is PROT_WRITE only and not PROT_READ|PROT_WRITE
//		memset(shm->buffer, clear, shm->samples * shm->samplebits/8);
	}
}


/*
=================
S_StaticSound
=================
*/
void S_StaticSound (sfx_t *sfx, vec3_t origin, float vol, float attenuation)
{
	channel_t	*ss;

	if (!sfx)
		return;

	if (total_channels == MAX_CHANNELS)
	{
		Con_Print("total_channels == MAX_CHANNELS\n");
		return;
	}

	if (!S_LoadSound (sfx, true))
		return;

	if (sfx->loopstart == -1)
		Con_DPrintf("Quake compatibility warning: Static sound \"%s\" is not looped\n", sfx->name);

	ss = &channels[total_channels++];
	memset(ss, 0, sizeof(*ss));
	ss->flags = CHANNELFLAG_FORCELOOP;
	ss->sfx = sfx;
	VectorCopy (origin, ss->origin);
	ss->master_vol = vol;
	ss->dist_mult = (attenuation/64) / sound_nominal_clip_dist;
	ss->end = paintedtime + sfx->total_length;
	ss->lastptime = paintedtime;

	SND_Spatialize (ss, true);
}


//=============================================================================

/*
===================
S_UpdateAmbientSounds
===================
*/
void S_UpdateAmbientSounds (void)
{
	float		vol;
	int			ambient_channel;
	channel_t	*chan;
	qbyte		ambientlevels[NUM_AMBIENTS];

	// LordHavoc: kill ambient sounds until proven otherwise
	for (ambient_channel = 0 ; ambient_channel < NUM_AMBIENTS;ambient_channel++)
		channels[ambient_channel].sfx = NULL;

	if (ambient_level.value <= 0 || !cl.worldmodel || !cl.worldmodel->brush.AmbientSoundLevelsForPoint)
		return;

	cl.worldmodel->brush.AmbientSoundLevelsForPoint(cl.worldmodel, listener_origin, ambientlevels, sizeof(ambientlevels));

// calc ambient sound levels
	for (ambient_channel = 0 ; ambient_channel< NUM_AMBIENTS ; ambient_channel++)
	{
		if (ambient_sfx[ambient_channel] &&
			(ambient_sfx[ambient_channel]->flags & SFXFLAG_SILENTLYMISSING))
			continue;
		chan = &channels[ambient_channel];
		chan->flags |= CHANNELFLAG_FORCELOOP;
		chan->sfx = ambient_sfx[ambient_channel];

		vol = ambient_level.value * ambientlevels[ambient_channel];
		if (vol < 8)
			vol = 0;

	// don't adjust volume too fast
		if (chan->master_vol < vol)
		{
			chan->master_vol += host_realframetime * ambient_fade.value;
			if (chan->master_vol > vol)
				chan->master_vol = vol;
		}
		else if (chan->master_vol > vol)
		{
			chan->master_vol -= host_realframetime * ambient_fade.value;
			if (chan->master_vol < vol)
				chan->master_vol = vol;
		}

		chan->leftvol = chan->rightvol = chan->master_vol;
	}
}


/*
============
S_Update

Called once each time through the main loop
============
*/
void S_Update(const matrix4x4_t *listenermatrix)
{
	unsigned int i, j, total;
	channel_t *ch, *combine;

	if (!snd_initialized.integer || (snd_blocked > 0))
		return;

	Matrix4x4_Invert_Simple(&listener_matrix, listenermatrix);
	Matrix4x4_OriginFromMatrix(listenermatrix, listener_origin);

// update general area ambient sound sources
	S_UpdateAmbientSounds ();

	combine = NULL;

// update spatialization for static and dynamic sounds
	ch = channels+NUM_AMBIENTS;
	for (i=NUM_AMBIENTS ; i<total_channels; i++, ch++)
	{
		if (!ch->sfx)
			continue;
		SND_Spatialize(ch, i >= MAX_DYNAMIC_CHANNELS + NUM_AMBIENTS);         // respatialize channel
		if (!ch->leftvol && !ch->rightvol)
			continue;

	// try to combine static sounds with a previous channel of the same
	// sound effect so we don't mix five torches every frame

		if (i > MAX_DYNAMIC_CHANNELS + NUM_AMBIENTS)
		{
		// see if it can just use the last one
			if (combine && combine->sfx == ch->sfx)
			{
				combine->leftvol += ch->leftvol;
				combine->rightvol += ch->rightvol;
				ch->leftvol = ch->rightvol = 0;
				continue;
			}
		// search for one
			combine = channels+MAX_DYNAMIC_CHANNELS + NUM_AMBIENTS;
			for (j=MAX_DYNAMIC_CHANNELS + NUM_AMBIENTS ; j<i; j++, combine++)
				if (combine->sfx == ch->sfx)
					break;

			if (j == total_channels)
				combine = NULL;
			else
			{
				if (combine != ch)
				{
					combine->leftvol += ch->leftvol;
					combine->rightvol += ch->rightvol;
					ch->leftvol = ch->rightvol = 0;
				}
				continue;
			}
		}
	}

//
// debugging output
//
	if (snd_show.integer)
	{
		total = 0;
		ch = channels;
		for (i=0 ; i<total_channels; i++, ch++)
			if (ch->sfx && (ch->leftvol || ch->rightvol) )
				total++;

		Con_Printf("----(%u)----\n", total);
	}

// mix some sound
	S_Update_();
}

void GetSoundtime(void)
{
	int		samplepos;
	static	int		buffers;
	static	int		oldsamplepos;
	int		fullsamples;

	fullsamples = shm->samples / shm->format.channels;

// it is possible to miscount buffers if it has wrapped twice between
// calls to S_Update.  Oh well.
	samplepos = SNDDMA_GetDMAPos();

	if (samplepos < oldsamplepos)
	{
		buffers++;					// buffer wrapped

		if (paintedtime > 0x40000000)
		{	// time to chop things off to avoid 32 bit limits
			buffers = 0;
			paintedtime = fullsamples;
			S_StopAllSounds (true);
		}
	}
	oldsamplepos = samplepos;

	soundtime = buffers * fullsamples + samplepos / shm->format.channels;
}

void IN_Accumulate (void);

void S_ExtraUpdate (void)
{

#ifdef USE_DSOUND
	IN_Accumulate ();
#endif

	if (snd_noextraupdate.integer)
		return;		// don't pollute timings
	S_Update_();
}

void S_Update_(void)
{
	unsigned        endtime;
	int				samps;

	if (!sound_started || (snd_blocked > 0))
		return;

// Updates DMA time
	GetSoundtime();

// check to make sure that we haven't overshot
	if (paintedtime < soundtime)
		paintedtime = soundtime;

// mix ahead of current position
	endtime = soundtime + _snd_mixahead.value * shm->format.speed;
	samps = shm->samples >> (shm->format.channels - 1);
	if (endtime > (unsigned int)(soundtime + samps))
		endtime = soundtime + samps;

#ifdef USE_DSOUND
// if the buffer was lost or stopped, restore it and/or restart it
	{
		DWORD	dwStatus;

		if (pDSBuf)
		{
			if (pDSBuf->lpVtbl->GetStatus (pDSBuf, &dwStatus) != DS_OK)
				Con_Print("Couldn't get sound buffer status\n");

			if (dwStatus & DSBSTATUS_BUFFERLOST)
				pDSBuf->lpVtbl->Restore (pDSBuf);

			if (!(dwStatus & DSBSTATUS_PLAYING))
				pDSBuf->lpVtbl->Play(pDSBuf, 0, 0, DSBPLAY_LOOPING);
		}
	}
#endif

	S_PaintChannels (endtime);

	SNDDMA_Submit ();
}

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

console functions

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

static void S_Play_Common(float fvol, float attenuation)
{
	int 	i, ch_ind;
	char name[256];
	sfx_t	*sfx;

	i = 1;
	while (i<Cmd_Argc())
	{
		if (!strrchr(Cmd_Argv(i), '.'))
			snprintf(name, sizeof(name), "%s.wav", Cmd_Argv(i));
		else
			strlcpy(name, Cmd_Argv(i), sizeof(name));
		sfx = S_PrecacheSound(name, true, true);

		// If we need to get the volume from the command line
		if (fvol == -1.0f)
		{
			fvol = atof(Cmd_Argv(i+1));
			i += 2;
		}
		else
			i++;

		ch_ind = S_StartSound(-1, 0, sfx, listener_origin, fvol, attenuation);
		if (ch_ind >= 0)
			channels[ch_ind].flags |= CHANNELFLAG_LOCALSOUND;
	}
}

void S_Play(void)
{
	S_Play_Common (1.0f, 1.0f);
}

void S_Play2(void)
{
	S_Play_Common (1.0f, 0.0f);
}

void S_PlayVol(void)
{
	S_Play_Common (-1.0f, 0.0f);
}

void S_SoundList(void)
{
	int		i;
	sfx_t	*sfx;
	int		size, total;

	total = 0;
	for (sfx=known_sfx, i=0 ; i<num_sfx ; i++, sfx++)
	{
		if (sfx->fetcher != NULL)
		{
			size = sfx->mempool->totalsize;
			total += size;
			Con_Printf ("%c%c(%2db, %6s) %8i : %s\n",
						(sfx->loopstart >= 0) ? 'L' : ' ',
						(sfx->flags & SFXFLAG_STREAMED) ? 'S' : ' ',
						sfx->format.width * 8,
						(sfx->format.channels == 2) ? "stereo" : "mono",
						size,
						sfx->name);
		}
	}
	Con_Printf("Total resident: %i\n", total);
}


void S_LocalSound (const char *sound, qboolean stdpath)
{
	sfx_t	*sfx;
	int		ch_ind;

	if (!snd_initialized.integer || nosound.integer)
		return;

	sfx = S_PrecacheSound (sound, true, stdpath);
	if (!sfx)
	{
		Con_Printf("S_LocalSound: can't precache %s\n", sound);
		return;
	}

	ch_ind = S_StartSound (cl.viewentity, 0, sfx, vec3_origin, 1, 1);
	if (ch_ind >= 0)
		channels[ch_ind].flags |= CHANNELFLAG_LOCALSOUND;
}