Mercurial > sdl-ios-xcode
annotate src/audio/SDL_mixer.c @ 1052:68f607298ca9
Some work on using accelerated alpha blits with hardware surfaces.
From Stephane Marchesin's fork, don't know who originally wrote it.
| author | Ryan C. Gordon <icculus@icculus.org> |
|---|---|
| date | Sun, 17 Apr 2005 10:40:41 +0000 |
| parents | b8d311d90021 |
| children | c9b51268668f |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 2 SDL - Simple DirectMedia Layer | |
|
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3 Copyright (C) 1997-2004 Sam Lantinga |
| 0 | 4 |
| 5 This library is free software; you can redistribute it and/or | |
| 6 modify it under the terms of the GNU Library General Public | |
| 7 License as published by the Free Software Foundation; either | |
| 8 version 2 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 Library General Public License for more details. | |
| 14 | |
| 15 You should have received a copy of the GNU Library General Public | |
| 16 License along with this library; if not, write to the Free | |
| 17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
| 18 | |
| 19 Sam Lantinga | |
|
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20 slouken@libsdl.org |
| 0 | 21 */ |
| 22 | |
| 23 #ifdef SAVE_RCSID | |
| 24 static char rcsid = | |
| 25 "@(#) $Id$"; | |
| 26 #endif | |
| 27 | |
| 28 /* This provides the default mixing callback for the SDL audio routines */ | |
| 29 | |
| 30 #include <stdio.h> | |
| 31 #include <stdlib.h> | |
| 32 #include <string.h> | |
| 33 | |
| 34 #include "SDL_audio.h" | |
| 35 #include "SDL_mutex.h" | |
| 36 #include "SDL_timer.h" | |
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37 #include "SDL_cpuinfo.h" |
| 0 | 38 #include "SDL_sysaudio.h" |
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39 #include "SDL_cpuinfo.h" |
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40 #include "SDL_mixer_MMX.h" |
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41 #include "SDL_mixer_MMX_VC.h" |
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42 #include "SDL_mixer_m68k.h" |
| 0 | 43 |
| 44 /* This table is used to add two sound values together and pin | |
| 45 * the value to avoid overflow. (used with permission from ARDI) | |
| 46 * Changed to use 0xFE instead of 0xFF for better sound quality. | |
| 47 */ | |
| 48 static const Uint8 mix8[] = | |
| 49 { | |
| 50 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
| 51 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
| 52 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
| 53 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
| 54 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
| 55 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
| 56 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
| 57 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
| 58 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
| 59 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
| 60 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, | |
| 61 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x02, 0x03, | |
| 62 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, | |
| 63 0x0F, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, | |
| 64 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20, 0x21, 0x22, 0x23, 0x24, | |
| 65 0x25, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F, | |
| 66 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, | |
| 67 0x3B, 0x3C, 0x3D, 0x3E, 0x3F, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, | |
| 68 0x46, 0x47, 0x48, 0x49, 0x4A, 0x4B, 0x4C, 0x4D, 0x4E, 0x4F, 0x50, | |
| 69 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5A, 0x5B, | |
| 70 0x5C, 0x5D, 0x5E, 0x5F, 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, | |
| 71 0x67, 0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x6F, 0x70, 0x71, | |
| 72 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7A, 0x7B, 0x7C, | |
| 73 0x7D, 0x7E, 0x7F, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, | |
| 74 0x88, 0x89, 0x8A, 0x8B, 0x8C, 0x8D, 0x8E, 0x8F, 0x90, 0x91, 0x92, | |
| 75 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9A, 0x9B, 0x9C, 0x9D, | |
| 76 0x9E, 0x9F, 0xA0, 0xA1, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6, 0xA7, 0xA8, | |
| 77 0xA9, 0xAA, 0xAB, 0xAC, 0xAD, 0xAE, 0xAF, 0xB0, 0xB1, 0xB2, 0xB3, | |
| 78 0xB4, 0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xBB, 0xBC, 0xBD, 0xBE, | |
| 79 0xBF, 0xC0, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, | |
| 80 0xCA, 0xCB, 0xCC, 0xCD, 0xCE, 0xCF, 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, | |
| 81 0xD5, 0xD6, 0xD7, 0xD8, 0xD9, 0xDA, 0xDB, 0xDC, 0xDD, 0xDE, 0xDF, | |
| 82 0xE0, 0xE1, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8, 0xE9, 0xEA, | |
| 83 0xEB, 0xEC, 0xED, 0xEE, 0xEF, 0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, | |
| 84 0xF6, 0xF7, 0xF8, 0xF9, 0xFA, 0xFB, 0xFC, 0xFD, 0xFE, 0xFE, 0xFE, | |
| 85 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
| 86 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
| 87 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
| 88 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
| 89 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
| 90 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
| 91 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
| 92 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
| 93 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
| 94 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
| 95 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, | |
| 96 0xFE, 0xFE, 0xFE, 0xFE, 0xFE, 0xFE | |
| 97 }; | |
| 98 | |
| 99 /* The volume ranges from 0 - 128 */ | |
| 100 #define ADJUST_VOLUME(s, v) (s = (s*v)/SDL_MIX_MAXVOLUME) | |
| 101 #define ADJUST_VOLUME_U8(s, v) (s = (((s-128)*v)/SDL_MIX_MAXVOLUME)+128) | |
| 102 | |
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103 void SDL_MixAudio (Uint8 *dst, const Uint8 *src, Uint32 len, int volume) |
| 0 | 104 { |
| 105 Uint16 format; | |
| 106 | |
| 107 if ( volume == 0 ) { | |
| 108 return; | |
| 109 } | |
| 110 /* Mix the user-level audio format */ | |
| 111 if ( current_audio ) { | |
| 112 if ( current_audio->convert.needed ) { | |
| 113 format = current_audio->convert.src_format; | |
| 114 } else { | |
| 115 format = current_audio->spec.format; | |
| 116 } | |
| 117 } else { | |
| 118 /* HACK HACK HACK */ | |
| 119 format = AUDIO_S16; | |
| 120 } | |
| 121 switch (format) { | |
| 122 | |
| 123 case AUDIO_U8: { | |
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124 #if defined(__M68000__) && defined(__GNUC__) |
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125 SDL_MixAudio_m68k_U8((char*)dst,(char*)src,(unsigned long)len,(long)volume,(char *)mix8); |
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126 #else |
| 0 | 127 Uint8 src_sample; |
| 128 | |
| 129 while ( len-- ) { | |
| 130 src_sample = *src; | |
| 131 ADJUST_VOLUME_U8(src_sample, volume); | |
| 132 *dst = mix8[*dst+src_sample]; | |
| 133 ++dst; | |
| 134 ++src; | |
| 135 } | |
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136 #endif |
| 0 | 137 } |
| 138 break; | |
| 139 | |
| 140 case AUDIO_S8: { | |
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141 #if defined(i386) && defined(__GNUC__) && defined(USE_ASMBLIT) |
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142 if (SDL_HasMMX()) |
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143 { |
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144 SDL_MixAudio_MMX_S8((char*)dst,(char*)src,(unsigned int)len,(int)volume); |
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145 } |
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146 else |
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147 #endif |
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148 #if defined(USE_ASM_MIXER_VC) |
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149 if (SDL_HasMMX()) |
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150 { |
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151 SDL_MixAudio_MMX_S8_VC((char*)dst,(char*)src,(unsigned int)len,(int)volume); |
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152 } |
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153 else |
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154 #endif |
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155 #if defined(__M68000__) && defined(__GNUC__) |
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156 SDL_MixAudio_m68k_S8((char*)dst,(char*)src,(unsigned long)len,(long)volume); |
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157 #else |
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158 { |
| 0 | 159 Sint8 *dst8, *src8; |
| 160 Sint8 src_sample; | |
| 161 int dst_sample; | |
| 162 const int max_audioval = ((1<<(8-1))-1); | |
| 163 const int min_audioval = -(1<<(8-1)); | |
| 164 | |
| 165 src8 = (Sint8 *)src; | |
| 166 dst8 = (Sint8 *)dst; | |
| 167 while ( len-- ) { | |
| 168 src_sample = *src8; | |
| 169 ADJUST_VOLUME(src_sample, volume); | |
| 170 dst_sample = *dst8 + src_sample; | |
| 171 if ( dst_sample > max_audioval ) { | |
| 172 *dst8 = max_audioval; | |
| 173 } else | |
| 174 if ( dst_sample < min_audioval ) { | |
| 175 *dst8 = min_audioval; | |
| 176 } else { | |
| 177 *dst8 = dst_sample; | |
| 178 } | |
| 179 ++dst8; | |
| 180 ++src8; | |
| 181 } | |
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182 } |
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183 #endif |
| 0 | 184 } |
| 185 break; | |
| 186 | |
| 187 case AUDIO_S16LSB: { | |
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188 #if defined(i386) && defined(__GNUC__) && defined(USE_ASMBLIT) |
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189 if (SDL_HasMMX()) |
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190 { |
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191 SDL_MixAudio_MMX_S16((char*)dst,(char*)src,(unsigned int)len,(int)volume); |
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192 } |
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193 else |
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194 #elif defined(USE_ASM_MIXER_VC) |
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195 if (SDL_HasMMX()) |
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196 { |
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197 SDL_MixAudio_MMX_S16_VC((char*)dst,(char*)src,(unsigned int)len,(int)volume); |
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198 } |
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199 else |
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200 #endif |
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201 #if defined(__M68000__) && defined(__GNUC__) |
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202 SDL_MixAudio_m68k_S16LSB((short*)dst,(short*)src,(unsigned long)len,(long)volume); |
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203 #else |
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204 { |
| 0 | 205 Sint16 src1, src2; |
| 206 int dst_sample; | |
| 207 const int max_audioval = ((1<<(16-1))-1); | |
| 208 const int min_audioval = -(1<<(16-1)); | |
| 209 | |
| 210 len /= 2; | |
| 211 while ( len-- ) { | |
| 212 src1 = ((src[1])<<8|src[0]); | |
| 213 ADJUST_VOLUME(src1, volume); | |
| 214 src2 = ((dst[1])<<8|dst[0]); | |
| 215 src += 2; | |
| 216 dst_sample = src1+src2; | |
| 217 if ( dst_sample > max_audioval ) { | |
| 218 dst_sample = max_audioval; | |
| 219 } else | |
| 220 if ( dst_sample < min_audioval ) { | |
| 221 dst_sample = min_audioval; | |
| 222 } | |
| 223 dst[0] = dst_sample&0xFF; | |
| 224 dst_sample >>= 8; | |
| 225 dst[1] = dst_sample&0xFF; | |
| 226 dst += 2; | |
| 227 } | |
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228 } |
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229 #endif |
| 0 | 230 } |
| 231 break; | |
| 232 | |
| 233 case AUDIO_S16MSB: { | |
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234 #if defined(__M68000__) && defined(__GNUC__) |
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235 SDL_MixAudio_m68k_S16MSB((short*)dst,(short*)src,(unsigned long)len,(long)volume); |
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236 #else |
| 0 | 237 Sint16 src1, src2; |
| 238 int dst_sample; | |
| 239 const int max_audioval = ((1<<(16-1))-1); | |
| 240 const int min_audioval = -(1<<(16-1)); | |
| 241 | |
| 242 len /= 2; | |
| 243 while ( len-- ) { | |
| 244 src1 = ((src[0])<<8|src[1]); | |
| 245 ADJUST_VOLUME(src1, volume); | |
| 246 src2 = ((dst[0])<<8|dst[1]); | |
| 247 src += 2; | |
| 248 dst_sample = src1+src2; | |
| 249 if ( dst_sample > max_audioval ) { | |
| 250 dst_sample = max_audioval; | |
| 251 } else | |
| 252 if ( dst_sample < min_audioval ) { | |
| 253 dst_sample = min_audioval; | |
| 254 } | |
| 255 dst[1] = dst_sample&0xFF; | |
| 256 dst_sample >>= 8; | |
| 257 dst[0] = dst_sample&0xFF; | |
| 258 dst += 2; | |
| 259 } | |
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260 #endif |
| 0 | 261 } |
| 262 break; | |
| 263 | |
| 264 default: /* If this happens... FIXME! */ | |
| 265 SDL_SetError("SDL_MixAudio(): unknown audio format"); | |
| 266 return; | |
| 267 } | |
| 268 } | |
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269 |