Mercurial > SDL_sound_CoreAudio
diff mixer/converters.c @ 486:859dd2ef3197
Added some seriously INCOMPLETE mixer code.
author | Ryan C. Gordon <icculus@icculus.org> |
---|---|
date | Sun, 27 Feb 2005 19:55:29 +0000 |
parents | |
children | 2df1f5c62d38 |
line wrap: on
line diff
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mixer/converters.c Sun Feb 27 19:55:29 2005 +0000 @@ -0,0 +1,208 @@ +/* + * SDL_sound -- An sound processing toolkit. + * Copyright (C) 2001 Ryan C. Gordon. + * + * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +/** + * This file implements the mixer itself. Largely, this is handled in the + * SDL audio callback. + * + * Documentation is in SDL_sound.h ... It's verbose, honest. :) + * + * Please see the file COPYING in the source's root directory. + * + * This file written by Ryan C. Gordon. (icculus@clutteredmind.org) + */ + +#if HAVE_CONFIG_H +# include <config.h> +#endif + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "SDL.h" +#include "SDL_thread.h" +#include "SDL_sound.h" + +#define __SDL_SOUND_INTERNAL__ +#include "SDL_sound_internal.h" + + +static void conv_mix_buf_u8_mono(void *userdata, Uint8 *_stream, int len) +{ + register Uint8 *stream = _stream; + register Uint32 i; + register Uint32 max = len * 2; + for (i = 0; i < max; i += 2) + { + *stream = (Uint8) ((((mixbuf[i]+mixbuf[i+1])*0.5f) * 127.0f) + 128.0f); + stream++; + } /* for */ +} /* conv_mix_buf_s8s */ + +static void conv_mix_buf_s8_mono(void *userdata, Uint8 *_stream, int len) +{ + register Uint32 i; + register Sint8 *stream = (Sint8 *) _stream; + register Uint32 max = len * 2; + for (i = 0; i < max; i += 2) + { + *stream = (Sint8) (((mixbuf[i] + mixbuf[i+1]) * 0.5f) * 127.0f); + stream++; + } /* for */ +} /* conv_mix_buf_s8s */ + +static void conv_mix_buf_s16_lsb_mono(void *userdata, Uint8 *_stream, int len) +{ + register Uint32 i; + register Sint16 *stream = (Sint16 *) _stream; + register Sint16 val; + register Uint32 max = len / 2; + for (i = 0; i < max; i += 2) + { + val = (Sint16) (((mixbuf[i] + mixbuf[i+1]) * 0.5f) * 32767.0f); + *stream = SDL_SwapLE16(val); + stream++; + } /* for */ +} /* conv_mix_buf_s16_lsb_mono */ + +static void conv_mix_buf_s16_msb_mono(void *userdata, Uint8 *_stream, int len) +{ + register Uint32 i; + register Sint16 *stream = (Sint16 *) _stream; + register Sint16 val; + register Uint32 max = len / 2; + for (i = 0; i < max; i += 2) + { + val = (Sint16) (((mixbuf[i] + mixbuf[i+1]) * 0.5f) * 32767.0f); + *stream = SDL_SwapBE16(val); + stream++; + } /* for */ +} /* conv_mix_buf_s16_msb_mono */ + +static void conv_mix_buf_u16_lsb_mono(void *userdata, Uint8 *_stream, int len) +{ + register Uint32 i; + register Uint16 *stream = (Uint16 *) _stream; + register Uint16 val; + register Uint32 max = len / 2; + for (i = 0; i < max; i += 2) + { + val = (Uint16)((((mixbuf[i]+mixbuf[i+1])*0.5f) * 32767.0f) + 32768.0f); + *stream = SDL_SwapLE16(val); + stream++; + } /* for */ +} /* conv_mix_buf_s16_lsb_mono */ + +static void conv_mix_buf_u16_msb_mono(void *userdata, Uint8 *_stream, int len) +{ + register Uint32 i; + register Uint16 *stream = (Uint16 *) _stream; + register Uint16 val; + register Uint32 max = len / 2; + for (i = 0; i < max; i += 2) + { + val = (Uint16)((((mixbuf[i]+mixbuf[i+1])*0.5f) * 32767.0f) + 32768.0f); + *stream = SDL_SwapBE16(val); + stream++; + } /* for */ +} /* conv_mix_buf_s16_lsb_mono */ + +static void conv_mix_buf_u8_stereo(void *userdata, Uint8 *_stream, int len) +{ + register Uint32 i; + register Uint8 *stream = _stream; + register Uint32 max = len; + for (i = 0; i < max; i++) + { + *stream = (Uint8) ((mixbuf[i] * 127.0f) + 128.0f); + stream++; + } /* for */ +} /* conv_mix_buf_s8s */ + +static void conv_mix_buf_s8_stereo(void *userdata, Uint8 *_stream, int len) +{ + register Uint32 i; + register Sint8 *stream = (Sint8 *) _stream; + register Uint32 max = len; + for (i = 0; i < max; i++) + { + *stream = (Sint8) (mixbuf[i] * 127.0f); + stream++; + } /* for */ +} /* conv_mix_buf_s8s */ + +static void conv_mix_buf_s16lsb_stereo(void *userdata, Uint8 *_stream, int len) +{ + register Uint32 i; + register Sint16 *stream = (Sint16 *) _stream; + register Sint16 val; + register Uint32 max = len / 2; + for (i = 0; i < max; i++) + { + val = (Sint16) (mixbuf[i] * 32767.0f); + *stream = SDL_SwapLE16(val); + stream++; + } /* for */ +} /* conv_mix_buf_s16_lsb_stereo */ + +static void conv_mix_buf_s16msb_stereo(void *userdata, Uint8 *_stream, int len) +{ + register Uint32 i; + register Sint16 *stream = (Sint16 *) _stream; + register Sint16 val; + register Uint32 max = len / 2; + for (i = 0; i < max; i++) + { + val = (Sint16) (mixbuf[i] * 32767.0f); + *stream = SDL_SwapBE16(val); + stream++; + } /* for */ +} /* conv_mix_buf_s16_msb_stereo */ + +static void conv_mix_buf_u16lsb_stereo(void *userdata, Uint8 *_stream, int len) +{ + register Uint32 i; + register Uint16 *stream = (Uint16 *) _stream; + register Uint16 val; + register Uint32 max = len / 2; + for (i = 0; i < max; i++) + { + val = (Uint16) ((mixbuf[i] * 32767.0f) + 32768.0f); + *stream = SDL_SwapLE16(val); + stream++; + } /* for */ +} /* conv_mix_buf_s16_lsb_stereo */ + +static void conv_mix_buf_u16msb_stereo(void *userdata, Uint8 *_stream, int len) +{ + register Uint32 i; + register Uint16 *stream = (Uint16 *) _stream; + register Uint16 val; + register Uint32 max = len / 2; + for (i = 0; i < max; i++) + { + val = (Uint16) ((mixbuf[i] * 32767.0f) + 32768.0f); + *stream = SDL_SwapBE16(val); + stream++; + } /* for */ +} /* conv_mix_buf_s16_msb_stereo */ + +/* end of converters.c ... */ +