ref: 2053768a9251cbd4c731681a3e1e04c800ad21f4
dir: /src/i_pcsound.c/
//
// Copyright(C) 2005-2014 Simon Howard
//
// 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.
//
// DESCRIPTION:
// System interface for PC speaker sound.
//
#include "SDL.h"
#include <string.h>
#include "doomtype.h"
#include "deh_str.h"
#include "i_sound.h"
#include "m_misc.h"
#include "w_wad.h"
#include "z_zone.h"
#include "pcsound.h"
#define TIMER_FREQ 1193181 /* hz */
static boolean pcs_initialized = false;
static SDL_mutex *sound_lock;
static boolean use_sfx_prefix;
static uint8_t *current_sound_lump = NULL;
static uint8_t *current_sound_pos = NULL;
static unsigned int current_sound_remaining = 0;
static int current_sound_handle = 0;
static int current_sound_lump_num = -1;
static const uint16_t divisors[] = {
0,
6818, 6628, 6449, 6279, 6087, 5906, 5736, 5575,
5423, 5279, 5120, 4971, 4830, 4697, 4554, 4435,
4307, 4186, 4058, 3950, 3836, 3728, 3615, 3519,
3418, 3323, 3224, 3131, 3043, 2960, 2875, 2794,
2711, 2633, 2560, 2485, 2415, 2348, 2281, 2213,
2153, 2089, 2032, 1975, 1918, 1864, 1810, 1757,
1709, 1659, 1612, 1565, 1521, 1478, 1435, 1395,
1355, 1316, 1280, 1242, 1207, 1173, 1140, 1107,
1075, 1045, 1015, 986, 959, 931, 905, 879,
854, 829, 806, 783, 760, 739, 718, 697,
677, 658, 640, 621, 604, 586, 570, 553,
538, 522, 507, 493, 479, 465, 452, 439,
427, 415, 403, 391, 380, 369, 359, 348,
339, 329, 319, 310, 302, 293, 285, 276,
269, 261, 253, 246, 239, 232, 226, 219,
213, 207, 201, 195, 190, 184, 179,
};
static void PCSCallbackFunc(int *duration, int *freq)
{
unsigned int tone;
*duration = 1000 / 140;
if (SDL_LockMutex(sound_lock) < 0)
{
*freq = 0;
return;
}
if (current_sound_lump != NULL && current_sound_remaining > 0)
{
// Read the next tone
tone = *current_sound_pos;
// Use the tone -> frequency lookup table. See pcspkr10.zip
// for a full discussion of this.
// Check we don't overflow the frequency table.
if (tone < arrlen(divisors) && divisors[tone] != 0)
{
*freq = (int) (TIMER_FREQ / divisors[tone]);
}
else
{
*freq = 0;
}
++current_sound_pos;
--current_sound_remaining;
}
else
{
*freq = 0;
}
SDL_UnlockMutex(sound_lock);
}
static boolean CachePCSLump(sfxinfo_t *sfxinfo)
{
int lumplen;
int headerlen;
// Free the current sound lump back to the cache
if (current_sound_lump != NULL)
{
W_ReleaseLumpNum(current_sound_lump_num);
current_sound_lump = NULL;
}
// Load from WAD
current_sound_lump = W_CacheLumpNum(sfxinfo->lumpnum, PU_STATIC);
lumplen = W_LumpLength(sfxinfo->lumpnum);
// Read header
if (current_sound_lump[0] != 0x00 || current_sound_lump[1] != 0x00)
{
return false;
}
headerlen = (current_sound_lump[3] << 8) | current_sound_lump[2];
if (headerlen > lumplen - 4)
{
return false;
}
// Header checks out ok
current_sound_remaining = headerlen;
current_sound_pos = current_sound_lump + 4;
current_sound_lump_num = sfxinfo->lumpnum;
return true;
}
// These Doom PC speaker sounds are not played - this can be seen in the
// Heretic source code, where there are remnants of this left over
// from Doom.
static boolean IsDisabledSound(sfxinfo_t *sfxinfo)
{
int i;
const char *disabled_sounds[] = {
"posact",
"bgact",
"dmact",
"dmpain",
"popain",
"sawidl",
};
for (i=0; i<arrlen(disabled_sounds); ++i)
{
if (!strcmp(sfxinfo->name, disabled_sounds[i]))
{
return true;
}
}
return false;
}
static int I_PCS_StartSound(sfxinfo_t *sfxinfo,
int channel,
int vol,
int sep,
int pitch)
{
int result;
if (!pcs_initialized)
{
return -1;
}
if (IsDisabledSound(sfxinfo))
{
return -1;
}
if (SDL_LockMutex(sound_lock) < 0)
{
return -1;
}
result = CachePCSLump(sfxinfo);
if (result)
{
current_sound_handle = channel;
}
SDL_UnlockMutex(sound_lock);
if (result)
{
return channel;
}
else
{
return -1;
}
}
static void I_PCS_StopSound(int handle)
{
if (!pcs_initialized)
{
return;
}
if (SDL_LockMutex(sound_lock) < 0)
{
return;
}
// If this is the channel currently playing, immediately end it.
if (current_sound_handle == handle)
{
current_sound_remaining = 0;
}
SDL_UnlockMutex(sound_lock);
}
//
// Retrieve the raw data lump index
// for a given SFX name.
//
static int I_PCS_GetSfxLumpNum(sfxinfo_t* sfx)
{
char namebuf[9];
if (use_sfx_prefix)
{
M_snprintf(namebuf, sizeof(namebuf), "dp%s", DEH_String(sfx->name));
}
else
{
M_StringCopy(namebuf, DEH_String(sfx->name), sizeof(namebuf));
}
return W_GetNumForName(namebuf);
}
static boolean I_PCS_SoundIsPlaying(int handle)
{
if (!pcs_initialized)
{
return false;
}
if (handle != current_sound_handle)
{
return false;
}
return current_sound_lump != NULL && current_sound_remaining > 0;
}
static boolean I_PCS_InitSound(boolean _use_sfx_prefix)
{
use_sfx_prefix = _use_sfx_prefix;
// Use the sample rate from the configuration file
PCSound_SetSampleRate(snd_samplerate);
// Initialize the PC speaker subsystem.
pcs_initialized = PCSound_Init(PCSCallbackFunc);
if (pcs_initialized)
{
sound_lock = SDL_CreateMutex();
}
return pcs_initialized;
}
static void I_PCS_ShutdownSound(void)
{
if (pcs_initialized)
{
PCSound_Shutdown();
}
}
static void I_PCS_UpdateSound(void)
{
// no-op.
}
void I_PCS_UpdateSoundParams(int channel, int vol, int sep)
{
// no-op.
}
static snddevice_t sound_pcsound_devices[] =
{
SNDDEVICE_PCSPEAKER,
};
sound_module_t sound_pcsound_module =
{
sound_pcsound_devices,
arrlen(sound_pcsound_devices),
I_PCS_InitSound,
I_PCS_ShutdownSound,
I_PCS_GetSfxLumpNum,
I_PCS_UpdateSound,
I_PCS_UpdateSoundParams,
I_PCS_StartSound,
I_PCS_StopSound,
I_PCS_SoundIsPlaying,
};