| 1 | /* |
| 2 | SDL - Simple DirectMedia Layer |
| 3 | Copyright (C) 1997-2009 Sam Lantinga |
| 4 | |
| 5 | This library is free software; you can redistribute it and/or |
| 6 | modify it under the terms of the GNU Lesser General Public |
| 7 | License as published by the Free Software Foundation; either |
| 8 | version 2.1 of the License, or (at your option) any later version. |
| 9 | |
| 10 | This library is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | Lesser General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU Lesser General Public |
| 16 | License along with this library; if not, write to the Free Software |
| 17 | Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| 18 | |
| 19 | Sam Lantinga |
| 20 | slouken@libsdl.org |
| 21 | */ |
| 22 | #include "SDL_config.h" |
| 23 | |
| 24 | /* This provides the default mixing callback for the SDL audio routines */ |
| 25 | |
| 26 | #include "SDL_cpuinfo.h" |
| 27 | #include "SDL_timer.h" |
| 28 | #include "SDL_audio.h" |
| 29 | #include "SDL_sysaudio.h" |
| 30 | #include "SDL_mixer_MMX.h" |
| 31 | #include "SDL_mixer_MMX_VC.h" |
| 32 | #include "SDL_mixer_m68k.h" |
| 33 | |
| 34 | /* This table is used to add two sound values together and pin |
| 35 | * the value to avoid overflow. (used with permission from ARDI) |
| 36 | * Changed to use 0xFE instead of 0xFF for better sound quality. |
| 37 | */ |
| 38 | static const Uint8 mix8[] = |
| 39 | { |
| 40 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, |
| 41 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, |
| 42 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, |
| 43 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, |
| 44 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, |
| 45 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, |
| 46 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, |
| 47 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, |
| 48 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, |
| 49 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, |
| 50 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, |
| 51 | 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x02, 0x03, |
| 52 | 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, |
| 53 | 0x0F, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, |
| 54 | 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20, 0x21, 0x22, 0x23, 0x24, |
| 55 | 0x25, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F, |
| 56 | 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, |
| 57 | 0x3B, 0x3C, 0x3D, 0x3E, 0x3F, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, |
| 58 | 0x46, 0x47, 0x48, 0x49, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x4F, 0x50, |
| 59 | 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5A, 0x5B, |
| 60 | 0x5C, 0x5D, 0x5E, 0x5F, 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, |
| 61 | 0x67, 0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x6F, 0x70, 0x71, |
| 62 | 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7A, 0x7B, 0x7C, |
| 63 | 0x7D, 0x7E, 0x7F, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, |
| 64 | 0x88, 0x89, 0x8A, 0x8B, 0x8C, 0x8D, 0x8E, 0x8F, 0x90, 0x91, 0x92, |
| 65 | 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9A, 0x9B, 0x9C, 0x9D, |
| 66 | 0x9E, 0x9F, 0xA0, 0xA1, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6, 0xA7, 0xA8, |
| 67 | 0xA9, 0xAA, 0xAB, 0xAC, 0xAD, 0xAE, 0xAF, 0xB0, 0xB1, 0xB2, 0xB3, |
| 68 | 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB, 0xBC, 0xBD, 0xBE, |
| 69 | 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, |
| 70 | 0xCA, 0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, |
| 71 | 0xD5, 0xD6, 0xD7, 0xD8, 0xD9, 0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF, |
| 72 | 0xE0, 0xE1, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8, 0xE9, 0xEA, |
| 73 | 0xEB, 0xEC, 0xED, 0xEE, 0xEF, 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, |
| 74 | 0xF6, 0xF7, 0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFE, 0xFE, |
| 75 | 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, |
| 76 | 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, |
| 77 | 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, |
| 78 | 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, |
| 79 | 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, |
| 80 | 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, |
| 81 | 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, |
| 82 | 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, |
| 83 | 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, |
| 84 | 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, |
| 85 | 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, |
| 86 | 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE |
| 87 | }; |
| 88 | |
| 89 | /* The volume ranges from 0 - 128 */ |
| 90 | #define ADJUST_VOLUME(s, v) (s = (s*v)/SDL_MIX_MAXVOLUME) |
| 91 | #define ADJUST_VOLUME_U8(s, v) (s = (((s-128)*v)/SDL_MIX_MAXVOLUME)+128) |
| 92 | |
| 93 | void SDL_MixAudio (Uint8 *dst, const Uint8 *src, Uint32 len, int volume) |
| 94 | { |
| 95 | Uint16 format; |
| 96 | |
| 97 | if ( volume == 0 ) { |
| 98 | return; |
| 99 | } |
| 100 | /* Mix the user-level audio format */ |
| 101 | if ( current_audio ) { |
| 102 | if ( current_audio->convert.needed ) { |
| 103 | format = current_audio->convert.src_format; |
| 104 | } else { |
| 105 | format = current_audio->spec.format; |
| 106 | } |
| 107 | } else { |
| 108 | /* HACK HACK HACK */ |
| 109 | format = AUDIO_S16; |
| 110 | } |
| 111 | switch (format) { |
| 112 | |
| 113 | case AUDIO_U8: { |
| 114 | #if defined(__GNUC__) && defined(__M68000__) && defined(SDL_ASSEMBLY_ROUTINES) |
| 115 | SDL_MixAudio_m68k_U8((char*)dst,(char*)src,(unsigned long)len,(long)volume,(char *)mix8); |
| 116 | #else |
| 117 | Uint8 src_sample; |
| 118 | |
| 119 | while ( len-- ) { |
| 120 | src_sample = *src; |
| 121 | ADJUST_VOLUME_U8(src_sample, volume); |
| 122 | *dst = mix8[*dst+src_sample]; |
| 123 | ++dst; |
| 124 | ++src; |
| 125 | } |
| 126 | #endif |
| 127 | } |
| 128 | break; |
| 129 | |
| 130 | case AUDIO_S8: { |
| 131 | #if defined(SDL_BUGGY_MMX_MIXERS) /* buggy, so we're disabling them. --ryan. */ |
| 132 | #if defined(__GNUC__) && defined(__i386__) && defined(SDL_ASSEMBLY_ROUTINES) |
| 133 | if (SDL_HasMMX()) |
| 134 | { |
| 135 | SDL_MixAudio_MMX_S8((char*)dst,(char*)src,(unsigned int)len,(int)volume); |
| 136 | } |
| 137 | else |
| 138 | #elif ((defined(_MSC_VER) && defined(_M_IX86)) || defined(__WATCOMC__)) && defined(SDL_ASSEMBLY_ROUTINES) |
| 139 | if (SDL_HasMMX()) |
| 140 | { |
| 141 | SDL_MixAudio_MMX_S8_VC((char*)dst,(char*)src,(unsigned int)len,(int)volume); |
| 142 | } |
| 143 | else |
| 144 | #endif |
| 145 | #endif |
| 146 | |
| 147 | #if defined(__GNUC__) && defined(__M68000__) && defined(SDL_ASSEMBLY_ROUTINES) |
| 148 | SDL_MixAudio_m68k_S8((char*)dst,(char*)src,(unsigned long)len,(long)volume); |
| 149 | #else |
| 150 | { |
| 151 | Sint8 *dst8, *src8; |
| 152 | Sint8 src_sample; |
| 153 | int dst_sample; |
| 154 | const int max_audioval = ((1<<(8-1))-1); |
| 155 | const int min_audioval = -(1<<(8-1)); |
| 156 | |
| 157 | src8 = (Sint8 *)src; |
| 158 | dst8 = (Sint8 *)dst; |
| 159 | while ( len-- ) { |
| 160 | src_sample = *src8; |
| 161 | ADJUST_VOLUME(src_sample, volume); |
| 162 | dst_sample = *dst8 + src_sample; |
| 163 | if ( dst_sample > max_audioval ) { |
| 164 | *dst8 = max_audioval; |
| 165 | } else |
| 166 | if ( dst_sample < min_audioval ) { |
| 167 | *dst8 = min_audioval; |
| 168 | } else { |
| 169 | *dst8 = dst_sample; |
| 170 | } |
| 171 | ++dst8; |
| 172 | ++src8; |
| 173 | } |
| 174 | } |
| 175 | #endif |
| 176 | } |
| 177 | break; |
| 178 | |
| 179 | case AUDIO_S16LSB: { |
| 180 | #if defined(SDL_BUGGY_MMX_MIXERS) /* buggy, so we're disabling them. --ryan. */ |
| 181 | #if defined(__GNUC__) && defined(__i386__) && defined(SDL_ASSEMBLY_ROUTINES) |
| 182 | if (SDL_HasMMX()) |
| 183 | { |
| 184 | SDL_MixAudio_MMX_S16((char*)dst,(char*)src,(unsigned int)len,(int)volume); |
| 185 | } |
| 186 | else |
| 187 | #elif ((defined(_MSC_VER) && defined(_M_IX86)) || defined(__WATCOMC__)) && defined(SDL_ASSEMBLY_ROUTINES) |
| 188 | if (SDL_HasMMX()) |
| 189 | { |
| 190 | SDL_MixAudio_MMX_S16_VC((char*)dst,(char*)src,(unsigned int)len,(int)volume); |
| 191 | } |
| 192 | else |
| 193 | #endif |
| 194 | #endif |
| 195 | |
| 196 | #if defined(__GNUC__) && defined(__M68000__) && defined(SDL_ASSEMBLY_ROUTINES) |
| 197 | SDL_MixAudio_m68k_S16LSB((short*)dst,(short*)src,(unsigned long)len,(long)volume); |
| 198 | #else |
| 199 | { |
| 200 | Sint16 src1, src2; |
| 201 | int dst_sample; |
| 202 | const int max_audioval = ((1<<(16-1))-1); |
| 203 | const int min_audioval = -(1<<(16-1)); |
| 204 | |
| 205 | len /= 2; |
| 206 | while ( len-- ) { |
| 207 | src1 = ((src[1])<<8|src[0]); |
| 208 | ADJUST_VOLUME(src1, volume); |
| 209 | src2 = ((dst[1])<<8|dst[0]); |
| 210 | src += 2; |
| 211 | dst_sample = src1+src2; |
| 212 | if ( dst_sample > max_audioval ) { |
| 213 | dst_sample = max_audioval; |
| 214 | } else |
| 215 | if ( dst_sample < min_audioval ) { |
| 216 | dst_sample = min_audioval; |
| 217 | } |
| 218 | dst[0] = dst_sample&0xFF; |
| 219 | dst_sample >>= 8; |
| 220 | dst[1] = dst_sample&0xFF; |
| 221 | dst += 2; |
| 222 | } |
| 223 | } |
| 224 | #endif |
| 225 | } |
| 226 | break; |
| 227 | |
| 228 | case AUDIO_S16MSB: { |
| 229 | #if defined(__GNUC__) && defined(__M68000__) && defined(SDL_ASSEMBLY_ROUTINES) |
| 230 | SDL_MixAudio_m68k_S16MSB((short*)dst,(short*)src,(unsigned long)len,(long)volume); |
| 231 | #else |
| 232 | Sint16 src1, src2; |
| 233 | int dst_sample; |
| 234 | const int max_audioval = ((1<<(16-1))-1); |
| 235 | const int min_audioval = -(1<<(16-1)); |
| 236 | |
| 237 | len /= 2; |
| 238 | while ( len-- ) { |
| 239 | src1 = ((src[0])<<8|src[1]); |
| 240 | ADJUST_VOLUME(src1, volume); |
| 241 | src2 = ((dst[0])<<8|dst[1]); |
| 242 | src += 2; |
| 243 | dst_sample = src1+src2; |
| 244 | if ( dst_sample > max_audioval ) { |
| 245 | dst_sample = max_audioval; |
| 246 | } else |
| 247 | if ( dst_sample < min_audioval ) { |
| 248 | dst_sample = min_audioval; |
| 249 | } |
| 250 | dst[1] = dst_sample&0xFF; |
| 251 | dst_sample >>= 8; |
| 252 | dst[0] = dst_sample&0xFF; |
| 253 | dst += 2; |
| 254 | } |
| 255 | #endif |
| 256 | } |
| 257 | break; |
| 258 | |
| 259 | default: /* If this happens... FIXME! */ |
| 260 | SDL_SetError("SDL_MixAudio(): unknown audio format"); |
| 261 | return; |
| 262 | } |
| 263 | } |
| 264 | |