/* Copyright (C) 1996-2001 Id Software, Inc. Copyright (C) 2002-2005 John Fitzgibbons and others Copyright (C) 2007-2008 Kristian Duske 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. */ // stolen from http://www.libsdl.org/projects/quake/ -- apologies, I don't know the author's name #include #include "quakedef.h" static dma_t the_shm; static int snd_inited; #define BUF_SIZE 512 static void paint_audio(void *unused, Uint8 *stream, int len) { if ( shm ) { shm->buffer = stream; shm->samplepos += len/(shm->samplebits/8)/2; // Check for samplepos overflow? S_PaintChannels (shm->samplepos); } } qboolean SNDDMA_Init(void) { SDL_AudioSpec desired, obtained; snd_inited = 0; /* Set up the desired format */ desired.freq = sndspeed.value; if (loadas8bit.value) { desired.format = AUDIO_U8; } else { if (SDL_BYTEORDER == SDL_BIG_ENDIAN) desired.format = AUDIO_S16MSB; else desired.format = AUDIO_S16LSB; } desired.channels = 2; desired.samples = BUF_SIZE; desired.callback = paint_audio; /* Open the audio device */ if ( SDL_OpenAudio(&desired, &obtained) < 0 ) { Con_Printf("Couldn't open SDL audio: %s\n", SDL_GetError()); return 0; } /* Make sure we can support the audio format */ switch (obtained.format) { case AUDIO_U8: /* Supported */ break; case AUDIO_S16LSB: case AUDIO_S16MSB: if ( ((obtained.format == AUDIO_S16LSB) && (SDL_BYTEORDER == SDL_LIL_ENDIAN)) || ((obtained.format == AUDIO_S16MSB) && (SDL_BYTEORDER == SDL_BIG_ENDIAN)) ) { /* Supported */ break; } /* Unsupported, fall through */; default: /* Not supported -- force SDL to do our bidding */ SDL_CloseAudio(); if ( SDL_OpenAudio(&desired, NULL) < 0 ) { Con_Printf("Couldn't open SDL audio: %s\n", SDL_GetError()); return 0; } memcpy(&obtained, &desired, sizeof(desired)); break; } SDL_PauseAudio(0); /* Fill the audio DMA information block */ shm = &the_shm; shm->splitbuffer = 0; shm->samplebits = (obtained.format & 0xFF); shm->speed = obtained.freq; shm->channels = obtained.channels; shm->samples = obtained.samples*shm->channels; shm->samplepos = 0; shm->submission_chunk = 1; shm->buffer = NULL; snd_inited = 1; return 1; } int SNDDMA_GetDMAPos(void) { return shm->samplepos; } void SNDDMA_Shutdown(void) { if (snd_inited) { SDL_CloseAudio(); snd_inited = 0; } }