Quake-2

snd_mem.c (6844B)

---

 /*
 Copyright (C) 1997-2001 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_mem.c: sound caching
 
 #include "client.h"
 #include "snd_loc.h"
 
 int			cache_full_cycle;
 
 byte *S_Alloc (int size);
 
 /*
 ================
 ResampleSfx
 ================
 */
 void ResampleSfx (sfx_t *sfx, int inrate, int inwidth, byte *data)
 {
 	int		outcount;
 	int		srcsample;
 	float	stepscale;
 	int		i;
 	int		sample, samplefrac, fracstep;
 	sfxcache_t	*sc;
 	
 	sc = sfx->cache;
 	if (!sc)
 		return;
 
 	stepscale = (float)inrate / dma.speed;	// this is usually 0.5, 1, or 2
 
 	outcount = sc->length / stepscale;
 	sc->length = outcount;
 	if (sc->loopstart != -1)
 		sc->loopstart = sc->loopstart / stepscale;
 
 	sc->speed = dma.speed;
 	if (s_loadas8bit->value)
 		sc->width = 1;
 	else
 		sc->width = inwidth;
 	sc->stereo = 0;
 
 // resample / decimate to the current source rate
 
 	if (stepscale == 1 && inwidth == 1 && sc->width == 1)
 	{
 // fast special case
 		for (i=0 ; i<outcount ; i++)
 			((signed char *)sc->data)[i]
 			= (int)( (unsigned char)(data[i]) - 128);
 	}
 	else
 	{
 // general case
 		samplefrac = 0;
 		fracstep = stepscale*256;
 		for (i=0 ; i<outcount ; i++)
 		{
 			srcsample = samplefrac >> 8;
 			samplefrac += fracstep;
 			if (inwidth == 2)
 				sample = LittleShort ( ((short *)data)[srcsample] );
 			else
 				sample = (int)( (unsigned char)(data[srcsample]) - 128) << 8;
 			if (sc->width == 2)
 				((short *)sc->data)[i] = sample;
 			else
 				((signed char *)sc->data)[i] = sample >> 8;
 		}
 	}
 }
 
 //=============================================================================
 
 /*
 ==============
 S_LoadSound
 ==============
 */
 sfxcache_t *S_LoadSound (sfx_t *s)
 {
     char	namebuffer[MAX_QPATH];
 	byte	*data;
 	wavinfo_t	info;
 	int		len;
 	float	stepscale;
 	sfxcache_t	*sc;
 	int		size;
 	char	*name;
 
 	if (s->name[0] == '*')
 		return NULL;
 
 // see if still in memory
 	sc = s->cache;
 	if (sc)
 		return sc;
 
 //Com_Printf ("S_LoadSound: %x\n", (int)stackbuf);
 // load it in
 	if (s->truename)
 		name = s->truename;
 	else
 		name = s->name;
 
 	if (name[0] == '#')
 		strcpy(namebuffer, &name[1]);
 	else
 		Com_sprintf (namebuffer, sizeof(namebuffer), "sound/%s", name);
 
 //	Com_Printf ("loading %s\n",namebuffer);
 
 	size = FS_LoadFile (namebuffer, (void **)&data);
 
 	if (!data)
 	{
 		Com_DPrintf ("Couldn't load %s\n", namebuffer);
 		return NULL;
 	}
 
 	info = GetWavinfo (s->name, data, size);
 	if (info.channels != 1)
 	{
 		Com_Printf ("%s is a stereo sample\n",s->name);
 		FS_FreeFile (data);
 		return NULL;
 	}
 
 	stepscale = (float)info.rate / dma.speed;	
 	len = info.samples / stepscale;
 
 	len = len * info.width * info.channels;
 
 	sc = s->cache = Z_Malloc (len + sizeof(sfxcache_t));
 	if (!sc)
 	{
 		FS_FreeFile (data);
 		return NULL;
 	}
 	
 	sc->length = info.samples;
 	sc->loopstart = info.loopstart;
 	sc->speed = info.rate;
 	sc->width = info.width;
 	sc->stereo = info.channels;
 
 	ResampleSfx (s, sc->speed, sc->width, data + info.dataofs);
 
 	FS_FreeFile (data);
 
 	return sc;
 }
 
 
 
 /*
 ===============================================================================
 
 WAV loading
 
 ===============================================================================
 */
 
 
 byte	*data_p;
 byte 	*iff_end;
 byte 	*last_chunk;
 byte 	*iff_data;
 int 	iff_chunk_len;
 
 
 short GetLittleShort(void)
 {
 	short val = 0;
 	val = *data_p;
 	val = val + (*(data_p+1)<<8);
 	data_p += 2;
 	return val;
 }
 
 int GetLittleLong(void)
 {
 	int val = 0;
 	val = *data_p;
 	val = val + (*(data_p+1)<<8);
 	val = val + (*(data_p+2)<<16);
 	val = val + (*(data_p+3)<<24);
 	data_p += 4;
 	return val;
 }
 
 void FindNextChunk(char *name)
 {
 	while (1)
 	{
 		data_p=last_chunk;
 
 		if (data_p >= iff_end)
 		{	// didn't find the chunk
 			data_p = NULL;
 			return;
 		}
 		
 		data_p += 4;
 		iff_chunk_len = GetLittleLong();
 		if (iff_chunk_len < 0)
 		{
 			data_p = NULL;
 			return;
 		}
 //		if (iff_chunk_len > 1024*1024)
 //			Sys_Error ("FindNextChunk: %i length is past the 1 meg sanity limit", iff_chunk_len);
 		data_p -= 8;
 		last_chunk = data_p + 8 + ( (iff_chunk_len + 1) & ~1 );
 		if (!strncmp(data_p, name, 4))
 			return;
 	}
 }
 
 void FindChunk(char *name)
 {
 	last_chunk = iff_data;
 	FindNextChunk (name);
 }
 
 
 void DumpChunks(void)
 {
 	char	str[5];
 	
 	str[4] = 0;
 	data_p=iff_data;
 	do
 	{
 		memcpy (str, data_p, 4);
 		data_p += 4;
 		iff_chunk_len = GetLittleLong();
 		Com_Printf ("0x%x : %s (%d)\n", (int)(data_p - 4), str, iff_chunk_len);
 		data_p += (iff_chunk_len + 1) & ~1;
 	} while (data_p < iff_end);
 }
 
 /*
 ============
 GetWavinfo
 ============
 */
 wavinfo_t GetWavinfo (char *name, byte *wav, int wavlength)
 {
 	wavinfo_t	info;
 	int     i;
 	int     format;
 	int		samples;
 
 	memset (&info, 0, sizeof(info));
 
 	if (!wav)
 		return info;
 		
 	iff_data = wav;
 	iff_end = wav + wavlength;
 
 // find "RIFF" chunk
 	FindChunk("RIFF");
 	if (!(data_p && !strncmp(data_p+8, "WAVE", 4)))
 	{
 		Com_Printf("Missing RIFF/WAVE chunks\n");
 		return info;
 	}
 
 // get "fmt " chunk
 	iff_data = data_p + 12;
 // DumpChunks ();
 
 	FindChunk("fmt ");
 	if (!data_p)
 	{
 		Com_Printf("Missing fmt chunk\n");
 		return info;
 	}
 	data_p += 8;
 	format = GetLittleShort();
 	if (format != 1)
 	{
 		Com_Printf("Microsoft PCM format only\n");
 		return info;
 	}
 
 	info.channels = GetLittleShort();
 	info.rate = GetLittleLong();
 	data_p += 4+2;
 	info.width = GetLittleShort() / 8;
 
 // get cue chunk
 	FindChunk("cue ");
 	if (data_p)
 	{
 		data_p += 32;
 		info.loopstart = GetLittleLong();
 //		Com_Printf("loopstart=%d\n", sfx->loopstart);
 
 	// if the next chunk is a LIST chunk, look for a cue length marker
 		FindNextChunk ("LIST");
 		if (data_p)
 		{
 			if (!strncmp (data_p + 28, "mark", 4))
 			{	// this is not a proper parse, but it works with cooledit...
 				data_p += 24;
 				i = GetLittleLong ();	// samples in loop
 				info.samples = info.loopstart + i;
 //				Com_Printf("looped length: %i\n", i);
 			}
 		}
 	}
 	else
 		info.loopstart = -1;
 
 // find data chunk
 	FindChunk("data");
 	if (!data_p)
 	{
 		Com_Printf("Missing data chunk\n");
 		return info;
 	}
 
 	data_p += 4;
 	samples = GetLittleLong () / info.width;
 
 	if (info.samples)
 	{
 		if (samples < info.samples)
 			Com_Error (ERR_DROP, "Sound %s has a bad loop length", name);
 	}
 	else
 		info.samples = samples;
 
 	info.dataofs = data_p - wav;
 	
 	return info;
 }