diff options
Diffstat (limited to 'distrib/sdl-1.2.15/src/audio/SDL_mixer.c')
-rw-r--r-- | distrib/sdl-1.2.15/src/audio/SDL_mixer.c | 264 |
1 files changed, 264 insertions, 0 deletions
diff --git a/distrib/sdl-1.2.15/src/audio/SDL_mixer.c b/distrib/sdl-1.2.15/src/audio/SDL_mixer.c new file mode 100644 index 0000000..b5d4d8b --- /dev/null +++ b/distrib/sdl-1.2.15/src/audio/SDL_mixer.c @@ -0,0 +1,264 @@ +/* + SDL - Simple DirectMedia Layer + Copyright (C) 1997-2012 Sam Lantinga + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + This library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library; if not, write to the Free Software + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + + Sam Lantinga + slouken@libsdl.org +*/ +#include "SDL_config.h" + +/* This provides the default mixing callback for the SDL audio routines */ + +#include "SDL_cpuinfo.h" +#include "SDL_timer.h" +#include "SDL_audio.h" +#include "SDL_sysaudio.h" +#include "SDL_mixer_MMX.h" +#include "SDL_mixer_MMX_VC.h" +#include "SDL_mixer_m68k.h" + +/* This table is used to add two sound values together and pin + * the value to avoid overflow. (used with permission from ARDI) + * Changed to use 0xFE instead of 0xFF for better sound quality. + */ +static const Uint8 mix8[] = +{ + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x02, 0x03, + 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, + 0x0F, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, + 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20, 0x21, 0x22, 0x23, 0x24, + 0x25, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F, + 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, + 0x3B, 0x3C, 0x3D, 0x3E, 0x3F, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, + 0x46, 0x47, 0x48, 0x49, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x4F, 0x50, + 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5A, 0x5B, + 0x5C, 0x5D, 0x5E, 0x5F, 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, + 0x67, 0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x6F, 0x70, 0x71, + 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7A, 0x7B, 0x7C, + 0x7D, 0x7E, 0x7F, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, + 0x88, 0x89, 0x8A, 0x8B, 0x8C, 0x8D, 0x8E, 0x8F, 0x90, 0x91, 0x92, + 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9A, 0x9B, 0x9C, 0x9D, + 0x9E, 0x9F, 0xA0, 0xA1, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6, 0xA7, 0xA8, + 0xA9, 0xAA, 0xAB, 0xAC, 0xAD, 0xAE, 0xAF, 0xB0, 0xB1, 0xB2, 0xB3, + 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB, 0xBC, 0xBD, 0xBE, + 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, + 0xCA, 0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, + 0xD5, 0xD6, 0xD7, 0xD8, 0xD9, 0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF, + 0xE0, 0xE1, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8, 0xE9, 0xEA, + 0xEB, 0xEC, 0xED, 0xEE, 0xEF, 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, + 0xF6, 0xF7, 0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFE, 0xFE, + 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, + 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, + 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, + 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, + 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, + 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, + 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, + 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, + 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, + 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, + 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, + 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE +}; + +/* The volume ranges from 0 - 128 */ +#define ADJUST_VOLUME(s, v) (s = (s*v)/SDL_MIX_MAXVOLUME) +#define ADJUST_VOLUME_U8(s, v) (s = (((s-128)*v)/SDL_MIX_MAXVOLUME)+128) + +void SDL_MixAudio (Uint8 *dst, const Uint8 *src, Uint32 len, int volume) +{ + Uint16 format; + + if ( volume == 0 ) { + return; + } + /* Mix the user-level audio format */ + if ( current_audio ) { + if ( current_audio->convert.needed ) { + format = current_audio->convert.src_format; + } else { + format = current_audio->spec.format; + } + } else { + /* HACK HACK HACK */ + format = AUDIO_S16; + } + switch (format) { + + case AUDIO_U8: { +#if defined(__GNUC__) && (defined(__m68k__) && !defined(__mcoldfire__)) && defined(SDL_ASSEMBLY_ROUTINES) + SDL_MixAudio_m68k_U8((char*)dst,(char*)src,(unsigned long)len,(long)volume,(char *)mix8); +#else + Uint8 src_sample; + + while ( len-- ) { + src_sample = *src; + ADJUST_VOLUME_U8(src_sample, volume); + *dst = mix8[*dst+src_sample]; + ++dst; + ++src; + } +#endif + } + break; + + case AUDIO_S8: { +#if defined(SDL_BUGGY_MMX_MIXERS) /* buggy, so we're disabling them. --ryan. */ +#if defined(__GNUC__) && defined(__i386__) && defined(SDL_ASSEMBLY_ROUTINES) + if (SDL_HasMMX()) + { + SDL_MixAudio_MMX_S8((char*)dst,(char*)src,(unsigned int)len,(int)volume); + } + else +#elif ((defined(_MSC_VER) && defined(_M_IX86)) || defined(__WATCOMC__)) && defined(SDL_ASSEMBLY_ROUTINES) + if (SDL_HasMMX()) + { + SDL_MixAudio_MMX_S8_VC((char*)dst,(char*)src,(unsigned int)len,(int)volume); + } + else +#endif +#endif + +#if defined(__GNUC__) && (defined(__m68k__) && !defined(__mcoldfire__)) && defined(SDL_ASSEMBLY_ROUTINES) + SDL_MixAudio_m68k_S8((char*)dst,(char*)src,(unsigned long)len,(long)volume); +#else + { + Sint8 *dst8, *src8; + Sint8 src_sample; + int dst_sample; + const int max_audioval = ((1<<(8-1))-1); + const int min_audioval = -(1<<(8-1)); + + src8 = (Sint8 *)src; + dst8 = (Sint8 *)dst; + while ( len-- ) { + src_sample = *src8; + ADJUST_VOLUME(src_sample, volume); + dst_sample = *dst8 + src_sample; + if ( dst_sample > max_audioval ) { + *dst8 = max_audioval; + } else + if ( dst_sample < min_audioval ) { + *dst8 = min_audioval; + } else { + *dst8 = dst_sample; + } + ++dst8; + ++src8; + } + } +#endif + } + break; + + case AUDIO_S16LSB: { +#if defined(SDL_BUGGY_MMX_MIXERS) /* buggy, so we're disabling them. --ryan. */ +#if defined(__GNUC__) && defined(__i386__) && defined(SDL_ASSEMBLY_ROUTINES) + if (SDL_HasMMX()) + { + SDL_MixAudio_MMX_S16((char*)dst,(char*)src,(unsigned int)len,(int)volume); + } + else +#elif ((defined(_MSC_VER) && defined(_M_IX86)) || defined(__WATCOMC__)) && defined(SDL_ASSEMBLY_ROUTINES) + if (SDL_HasMMX()) + { + SDL_MixAudio_MMX_S16_VC((char*)dst,(char*)src,(unsigned int)len,(int)volume); + } + else +#endif +#endif + +#if defined(__GNUC__) && (defined(__m68k__) && !defined(__mcoldfire__)) && defined(SDL_ASSEMBLY_ROUTINES) + SDL_MixAudio_m68k_S16LSB((short*)dst,(short*)src,(unsigned long)len,(long)volume); +#else + { + Sint16 src1, src2; + int dst_sample; + const int max_audioval = ((1<<(16-1))-1); + const int min_audioval = -(1<<(16-1)); + + len /= 2; + while ( len-- ) { + src1 = ((src[1])<<8|src[0]); + ADJUST_VOLUME(src1, volume); + src2 = ((dst[1])<<8|dst[0]); + src += 2; + dst_sample = src1+src2; + if ( dst_sample > max_audioval ) { + dst_sample = max_audioval; + } else + if ( dst_sample < min_audioval ) { + dst_sample = min_audioval; + } + dst[0] = dst_sample&0xFF; + dst_sample >>= 8; + dst[1] = dst_sample&0xFF; + dst += 2; + } + } +#endif + } + break; + + case AUDIO_S16MSB: { +#if defined(__GNUC__) && (defined(__m68k__) && !defined(__mcoldfire__)) && defined(SDL_ASSEMBLY_ROUTINES) + SDL_MixAudio_m68k_S16MSB((short*)dst,(short*)src,(unsigned long)len,(long)volume); +#else + Sint16 src1, src2; + int dst_sample; + const int max_audioval = ((1<<(16-1))-1); + const int min_audioval = -(1<<(16-1)); + + len /= 2; + while ( len-- ) { + src1 = ((src[0])<<8|src[1]); + ADJUST_VOLUME(src1, volume); + src2 = ((dst[0])<<8|dst[1]); + src += 2; + dst_sample = src1+src2; + if ( dst_sample > max_audioval ) { + dst_sample = max_audioval; + } else + if ( dst_sample < min_audioval ) { + dst_sample = min_audioval; + } + dst[1] = dst_sample&0xFF; + dst_sample >>= 8; + dst[0] = dst_sample&0xFF; + dst += 2; + } +#endif + } + break; + + default: /* If this happens... FIXME! */ + SDL_SetError("SDL_MixAudio(): unknown audio format"); + return; + } +} + |