Xash3D FWGS engine.
 
 
 
 

269 lines
5.7 KiB

/*
s_backend.c - sound hardware output
Copyright (C) 2009 Uncle Mike
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 3 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.
*/
#include "common.h"
#include "platform/platform.h"
#if XASH_SOUND == SOUND_SDL
#include "sound.h"
#include <SDL.h>
#define SAMPLE_16BIT_SHIFT 1
#define SECONDARY_BUFFER_SIZE 0x10000
#if ! SDL_VERSION_ATLEAST( 2, 0, 0 )
#include <stdlib.h>
#define SDL_setenv setenv
#define SDL_GetCurrentAudioDriver() "legacysdl"
#define SDL_OpenAudioDevice( a, b, c, d, e ) SDL_OpenAudio( ( c ), ( d ) )
#define SDL_CloseAudioDevice( a ) SDL_CloseAudio()
#define SDL_PauseAudioDevice( a, b ) SDL_PauseAudio( ( b ) )
#define SDLash_IsAudioError( x ) ( x ) != 0
#else
#define SDLash_IsAudioError( x ) ( x ) == 0
#endif
/*
=======================================================================
Global variables. Must be visible to window-procedure function
so it can unlock and free the data block after it has been played.
=======================================================================
*/
static int sdl_dev;
//static qboolean snd_firsttime = true;
//static qboolean primary_format_set;
void SDL_SoundCallback( void *userdata, Uint8 *stream, int len )
{
int size = dma.samples << 1;
int pos = dma.samplepos << 1;
int wrapped = pos + len - size;
#if ! SDL_VERSION_ATLEAST( 2, 0, 0 )
if( !dma.buffer )
return;
#endif
if( wrapped < 0 )
{
memcpy( stream, dma.buffer + pos, len );
dma.samplepos += len >> 1;
}
else
{
int remaining = size - pos;
memcpy( stream, dma.buffer + pos, remaining );
memcpy( stream + remaining, dma.buffer, wrapped );
dma.samplepos = wrapped >> 1;
}
}
/*
==================
SNDDMA_Init
Try to find a sound device to mix for.
Returns false if nothing is found.
==================
*/
qboolean SNDDMA_Init( void )
{
SDL_AudioSpec desired, obtained;
int samplecount;
if( SDL_Init( SDL_INIT_AUDIO ) )
{
Con_Reportf( S_ERROR "Audio: SDL: %s \n", SDL_GetError( ) );
return false;
}
// even if we don't have PA
// we still can safely set env variables
SDL_setenv( "PULSE_PROP_application.name", GI->title, 1 );
SDL_setenv( "PULSE_PROP_media.role", "game", 1 );
memset( &desired, 0, sizeof( desired ) );
desired.freq = SOUND_DMA_SPEED;
desired.format = AUDIO_S16LSB;
desired.samples = 1024;
desired.channels = 2;
desired.callback = SDL_SoundCallback;
sdl_dev = SDL_OpenAudioDevice( NULL, 0, &desired, &obtained, 0 );
if( SDLash_IsAudioError( sdl_dev ))
{
Con_Printf( "Couldn't open SDL audio: %s\n", SDL_GetError( ) );
return false;
}
if( obtained.format != AUDIO_S16LSB )
{
Con_Printf( "SDL audio format %d unsupported.\n", obtained.format );
goto fail;
}
if( obtained.channels != 1 && obtained.channels != 2 )
{
Con_Printf( "SDL audio channels %d unsupported.\n", obtained.channels );
goto fail;
}
dma.format.speed = obtained.freq;
dma.format.channels = obtained.channels;
dma.format.width = 2;
samplecount = s_samplecount->value;
if( !samplecount )
samplecount = 0x8000;
dma.samples = samplecount * obtained.channels;
dma.buffer = Z_Calloc( dma.samples * 2 );
dma.samplepos = 0;
Con_Printf( "Using SDL audio driver: %s @ %d Hz\n", SDL_GetCurrentAudioDriver( ), obtained.freq );
SNDDMA_Activate( true );
dma.initialized = true;
return true;
fail:
SNDDMA_Shutdown( );
return false;
}
/*
==============
SNDDMA_GetDMAPos
return the current sample position (in mono samples read)
inside the recirculating dma buffer, so the mixing code will know
how many sample are required to fill it up.
===============
*/
int SNDDMA_GetDMAPos( void )
{
return dma.samplepos;
}
/*
==============
SNDDMA_GetSoundtime
update global soundtime
===============
*/
int SNDDMA_GetSoundtime( void )
{
static int buffers, oldsamplepos;
int samplepos, fullsamples;
fullsamples = dma.samples / 2;
// 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;
return ( buffers * fullsamples + samplepos / 2 );
}
/*
==============
SNDDMA_BeginPainting
Makes sure dma.buffer is valid
===============
*/
void SNDDMA_BeginPainting( void )
{
SDL_LockAudio( );
}
/*
==============
SNDDMA_Submit
Send sound to device if buffer isn't really the dma buffer
Also unlocks the dsound buffer
===============
*/
void SNDDMA_Submit( void )
{
SDL_UnlockAudio( );
}
/*
==============
SNDDMA_Shutdown
Reset the sound device for exiting
===============
*/
void SNDDMA_Shutdown( void )
{
Con_Printf( "Shutting down audio.\n" );
dma.initialized = false;
if( sdl_dev )
{
SNDDMA_Activate( false );
#if !XASH_EMSCRIPTEN
SDL_CloseAudioDevice( sdl_dev );
#endif
}
#if !XASH_EMSCRIPTEN
if( SDL_WasInit( SDL_INIT_AUDIO ) )
SDL_QuitSubSystem( SDL_INIT_AUDIO );
#endif
if( dma.buffer )
{
Mem_Free( dma.buffer );
dma.buffer = NULL;
}
}
/*
===========
SNDDMA_Activate
Called when the main window gains or loses focus.
The window have been destroyed and recreated
between a deactivate and an activate.
===========
*/
void SNDDMA_Activate( qboolean active )
{
SDL_PauseAudioDevice( sdl_dev, !active );
}
#endif // XASH_SOUND == SOUND_SDL