SDL_mixer.h
author Sam Lantinga <slouken@libsdl.org>
Tue, 21 Dec 2004 17:38:38 +0000
changeset 254 1ad5ff083036
parent 241 503416fca921
child 255 16119b6dc45a
permissions -rw-r--r--
Fixed building mod support on UNIX
We always build in music SDL_RWops support
     1 /*
     2     SDL_mixer:  An audio mixer library based on the SDL library
     3     Copyright (C) 1997-2004 Sam Lantinga
     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
    20     slouken@libsdl.org
    21 */
    22 
    23 /* $Id$ */
    24 
    25 #ifndef _SDL_MIXER_H
    26 #define _SDL_MIXER_H
    27 
    28 #include "SDL_types.h"
    29 #include "SDL_rwops.h"
    30 #include "SDL_audio.h"
    31 #include "SDL_byteorder.h"
    32 #include "SDL_version.h"
    33 #include "begin_code.h"
    34 
    35 /* Set up for C function definitions, even when using C++ */
    36 #ifdef __cplusplus
    37 extern "C" {
    38 #endif
    39 
    40 /* Printable format: "%d.%d.%d", MAJOR, MINOR, PATCHLEVEL
    41 */
    42 #define SDL_MIXER_MAJOR_VERSION	1
    43 #define SDL_MIXER_MINOR_VERSION	2
    44 #define SDL_MIXER_PATCHLEVEL	6
    45 
    46 /* This macro can be used to fill a version structure with the compile-time
    47  * version of the SDL_mixer library.
    48  */
    49 #define SDL_MIXER_VERSION(X)						\
    50 {									\
    51 	(X)->major = SDL_MIXER_MAJOR_VERSION;				\
    52 	(X)->minor = SDL_MIXER_MINOR_VERSION;				\
    53 	(X)->patch = SDL_MIXER_PATCHLEVEL;				\
    54 }
    55 
    56 /* Backwards compatibility */
    57 #define MIX_MAJOR_VERSION	SDL_MIXER_MAJOR_VERSION
    58 #define MIX_MINOR_VERSION	SDL_MIXER_MINOR_VERSION
    59 #define MIX_PATCHLEVEL		SDL_MIXER_PATCHLEVEL
    60 #define MIX_VERSION(X)		SDL_MIXER_VERSION(X)
    61 
    62 /* This function gets the version of the dynamically linked SDL_mixer library.
    63    it should NOT be used to fill a version structure, instead you should
    64    use the SDL_MIXER_VERSION() macro.
    65  */
    66 extern DECLSPEC const SDL_version * SDLCALL Mix_Linked_Version(void);
    67 
    68 
    69 /* The default mixer has 8 simultaneous mixing channels */
    70 #ifndef MIX_CHANNELS
    71 #define MIX_CHANNELS	8
    72 #endif
    73 
    74 /* Good default values for a PC soundcard */
    75 #define MIX_DEFAULT_FREQUENCY	22050
    76 #if SDL_BYTEORDER == SDL_LIL_ENDIAN
    77 #define MIX_DEFAULT_FORMAT	AUDIO_S16LSB
    78 #else
    79 #define MIX_DEFAULT_FORMAT	AUDIO_S16MSB
    80 #endif
    81 #define MIX_DEFAULT_CHANNELS	2
    82 #define MIX_MAX_VOLUME		128	/* Volume of a chunk */
    83 
    84 /* The internal format for an audio chunk */
    85 typedef struct {
    86 	int allocated;
    87 	Uint8 *abuf;
    88 	Uint32 alen;
    89 	Uint8 volume;		/* Per-sample volume, 0-128 */
    90 } Mix_Chunk;
    91 
    92 /* The different fading types supported */
    93 typedef enum {
    94 	MIX_NO_FADING,
    95 	MIX_FADING_OUT,
    96 	MIX_FADING_IN
    97 } Mix_Fading;
    98 
    99 typedef enum {
   100 	MUS_NONE,
   101 	MUS_CMD,
   102 	MUS_WAV,
   103 	MUS_MOD,
   104 	MUS_MID,
   105 	MUS_OGG,
   106 	MUS_MP3
   107 } Mix_MusicType;
   108 
   109 /* The internal format for a music chunk interpreted via mikmod */
   110 typedef struct _Mix_Music Mix_Music;
   111 
   112 /* Open the mixer with a certain audio format */
   113 extern DECLSPEC int SDLCALL Mix_OpenAudio(int frequency, Uint16 format, int channels,
   114 							int chunksize);
   115 
   116 /* Dynamically change the number of channels managed by the mixer.
   117    If decreasing the number of channels, the upper channels are
   118    stopped.
   119    This function returns the new number of allocated channels.
   120  */
   121 extern DECLSPEC int SDLCALL Mix_AllocateChannels(int numchans);
   122 
   123 /* Find out what the actual audio device parameters are.
   124    This function returns 1 if the audio has been opened, 0 otherwise.
   125  */
   126 extern DECLSPEC int SDLCALL Mix_QuerySpec(int *frequency,Uint16 *format,int *channels);
   127 
   128 /* Load a wave file or a music (.mod .s3m .it .xm) file */
   129 extern DECLSPEC Mix_Chunk * SDLCALL Mix_LoadWAV_RW(SDL_RWops *src, int freesrc);
   130 #define Mix_LoadWAV(file)	Mix_LoadWAV_RW(SDL_RWFromFile(file, "rb"), 1)
   131 extern DECLSPEC Mix_Music * SDLCALL Mix_LoadMUS(const char *file);
   132 
   133 /* Load a music file from an SDL_RWop object (Ogg and MikMod specific currently)
   134    Matt Campbell (matt@campbellhome.dhs.org) April 2000 */
   135 extern DECLSPEC Mix_Music * SDLCALL Mix_LoadMUS_RW(SDL_RWops *rw);
   136 
   137 /* Load a wave file of the mixer format from a memory buffer */
   138 extern DECLSPEC Mix_Chunk * SDLCALL Mix_QuickLoad_WAV(Uint8 *mem);
   139 
   140 /* Load raw audio data of the mixer format from a memory buffer */
   141 extern DECLSPEC Mix_Chunk * SDLCALL Mix_QuickLoad_RAW(Uint8 *mem, Uint32 len);
   142 
   143 /* Free an audio chunk previously loaded */
   144 extern DECLSPEC void SDLCALL Mix_FreeChunk(Mix_Chunk *chunk);
   145 extern DECLSPEC void SDLCALL Mix_FreeMusic(Mix_Music *music);
   146 
   147 /* Find out the music format of a mixer music, or the currently playing
   148    music, if 'music' is NULL.
   149 */
   150 extern DECLSPEC Mix_MusicType SDLCALL Mix_GetMusicType(const Mix_Music *music);
   151 
   152 /* Set a function that is called after all mixing is performed.
   153    This can be used to provide real-time visual display of the audio stream
   154    or add a custom mixer filter for the stream data.
   155 */
   156 extern DECLSPEC void SDLCALL Mix_SetPostMix(void (*mix_func)
   157                              (void *udata, Uint8 *stream, int len), void *arg);
   158 
   159 /* Add your own music player or additional mixer function.
   160    If 'mix_func' is NULL, the default music player is re-enabled.
   161  */
   162 extern DECLSPEC void SDLCALL Mix_HookMusic(void (*mix_func)
   163                           (void *udata, Uint8 *stream, int len), void *arg);
   164 
   165 /* Add your own callback when the music has finished playing.
   166    This callback is only called if the music finishes naturally.
   167  */
   168 extern DECLSPEC void SDLCALL Mix_HookMusicFinished(void (*music_finished)(void));
   169 
   170 /* Get a pointer to the user data for the current music hook */
   171 extern DECLSPEC void * SDLCALL Mix_GetMusicHookData(void);
   172 
   173 /*
   174  * Add your own callback when a channel has finished playing. NULL
   175  *  to disable callback. The callback may be called from the mixer's audio 
   176  *  callback or it could be called as a result of Mix_HaltChannel(), etc.
   177  *  do not call SDL_LockAudio() from this callback; you will either be 
   178  *  inside the audio callback, or SDL_mixer will explicitly lock the audio
   179  *  before calling your callback.
   180  */
   181 extern DECLSPEC void SDLCALL Mix_ChannelFinished(void (*channel_finished)(int channel));
   182 
   183 
   184 /* Special Effects API by ryan c. gordon. (icculus@linuxgames.com) */
   185 
   186 #define MIX_CHANNEL_POST  -2
   187 
   188 /* This is the format of a special effect callback:
   189  *
   190  *   myeffect(int chan, void *stream, int len, void *udata);
   191  *
   192  * (chan) is the channel number that your effect is affecting. (stream) is
   193  *  the buffer of data to work upon. (len) is the size of (stream), and
   194  *  (udata) is a user-defined bit of data, which you pass as the last arg of
   195  *  Mix_RegisterEffect(), and is passed back unmolested to your callback.
   196  *  Your effect changes the contents of (stream) based on whatever parameters
   197  *  are significant, or just leaves it be, if you prefer. You can do whatever
   198  *  you like to the buffer, though, and it will continue in its changed state
   199  *  down the mixing pipeline, through any other effect functions, then finally
   200  *  to be mixed with the rest of the channels and music for the final output
   201  *  stream.
   202  *
   203  * DO NOT EVER call SDL_LockAudio() from your callback function!
   204  */
   205 typedef void (*Mix_EffectFunc_t)(int chan, void *stream, int len, void *udata);
   206 
   207 /*
   208  * This is a callback that signifies that a channel has finished all its
   209  *  loops and has completed playback. This gets called if the buffer
   210  *  plays out normally, or if you call Mix_HaltChannel(), implicitly stop
   211  *  a channel via Mix_AllocateChannels(), or unregister a callback while
   212  *  it's still playing.
   213  *
   214  * DO NOT EVER call SDL_LockAudio() from your callback function!
   215  */
   216 typedef void (*Mix_EffectDone_t)(int chan, void *udata);
   217 
   218 
   219 /* Register a special effect function. At mixing time, the channel data is
   220  *  copied into a buffer and passed through each registered effect function.
   221  *  After it passes through all the functions, it is mixed into the final
   222  *  output stream. The copy to buffer is performed once, then each effect
   223  *  function performs on the output of the previous effect. Understand that
   224  *  this extra copy to a buffer is not performed if there are no effects
   225  *  registered for a given chunk, which saves CPU cycles, and any given
   226  *  effect will be extra cycles, too, so it is crucial that your code run
   227  *  fast. Also note that the data that your function is given is in the
   228  *  format of the sound device, and not the format you gave to Mix_OpenAudio(),
   229  *  although they may in reality be the same. This is an unfortunate but
   230  *  necessary speed concern. Use Mix_QuerySpec() to determine if you can
   231  *  handle the data before you register your effect, and take appropriate
   232  *  actions.
   233  * You may also specify a callback (Mix_EffectDone_t) that is called when
   234  *  the channel finishes playing. This gives you a more fine-grained control
   235  *  than Mix_ChannelFinished(), in case you need to free effect-specific
   236  *  resources, etc. If you don't need this, you can specify NULL.
   237  * You may set the callbacks before or after calling Mix_PlayChannel().
   238  * Things like Mix_SetPanning() are just internal special effect functions,
   239  *  so if you are using that, you've already incurred the overhead of a copy
   240  *  to a separate buffer, and that these effects will be in the queue with
   241  *  any functions you've registered. The list of registered effects for a
   242  *  channel is reset when a chunk finishes playing, so you need to explicitly
   243  *  set them with each call to Mix_PlayChannel*().
   244  * You may also register a special effect function that is to be run after
   245  *  final mixing occurs. The rules for these callbacks are identical to those
   246  *  in Mix_RegisterEffect, but they are run after all the channels and the
   247  *  music have been mixed into a single stream, whereas channel-specific
   248  *  effects run on a given channel before any other mixing occurs. These
   249  *  global effect callbacks are call "posteffects". Posteffects only have
   250  *  their Mix_EffectDone_t function called when they are unregistered (since
   251  *  the main output stream is never "done" in the same sense as a channel).
   252  *  You must unregister them manually when you've had enough. Your callback
   253  *  will be told that the channel being mixed is (MIX_CHANNEL_POST) if the
   254  *  processing is considered a posteffect.
   255  *
   256  * After all these effects have finished processing, the callback registered
   257  *  through Mix_SetPostMix() runs, and then the stream goes to the audio
   258  *  device. 
   259  *
   260  * DO NOT EVER call SDL_LockAudio() from your callback function!
   261  *
   262  * returns zero if error (no such channel), nonzero if added.
   263  *  Error messages can be retrieved from Mix_GetError().
   264  */
   265 extern DECLSPEC int SDLCALL Mix_RegisterEffect(int chan, Mix_EffectFunc_t f,
   266 					Mix_EffectDone_t d, void *arg);
   267 
   268 
   269 /* You may not need to call this explicitly, unless you need to stop an
   270  *  effect from processing in the middle of a chunk's playback.
   271  * Posteffects are never implicitly unregistered as they are for channels,
   272  *  but they may be explicitly unregistered through this function by
   273  *  specifying MIX_CHANNEL_POST for a channel.
   274  * returns zero if error (no such channel or effect), nonzero if removed.
   275  *  Error messages can be retrieved from Mix_GetError().
   276  */
   277 extern DECLSPEC int SDLCALL Mix_UnregisterEffect(int channel, Mix_EffectFunc_t f);
   278 
   279 
   280 /* You may not need to call this explicitly, unless you need to stop all
   281  *  effects from processing in the middle of a chunk's playback. Note that
   282  *  this will also shut off some internal effect processing, since
   283  *  Mix_SetPanning() and others may use this API under the hood. This is
   284  *  called internally when a channel completes playback.
   285  * Posteffects are never implicitly unregistered as they are for channels,
   286  *  but they may be explicitly unregistered through this function by
   287  *  specifying MIX_CHANNEL_POST for a channel.
   288  * returns zero if error (no such channel), nonzero if all effects removed.
   289  *  Error messages can be retrieved from Mix_GetError().
   290  */
   291 extern DECLSPEC int SDLCALL Mix_UnregisterAllEffects(int channel);
   292 
   293 
   294 #define MIX_EFFECTSMAXSPEED  "MIX_EFFECTSMAXSPEED"
   295 
   296 /*
   297  * These are the internally-defined mixing effects. They use the same API that
   298  *  effects defined in the application use, but are provided here as a
   299  *  convenience. Some effects can reduce their quality or use more memory in
   300  *  the name of speed; to enable this, make sure the environment variable
   301  *  MIX_EFFECTSMAXSPEED (see above) is defined before you call
   302  *  Mix_OpenAudio().
   303  */
   304 
   305 
   306 /* Set the panning of a channel. The left and right channels are specified
   307  *  as integers between 0 and 255, quietest to loudest, respectively.
   308  *
   309  * Technically, this is just individual volume control for a sample with
   310  *  two (stereo) channels, so it can be used for more than just panning.
   311  *  If you want real panning, call it like this:
   312  *
   313  *   Mix_SetPanning(channel, left, 255 - left);
   314  *
   315  * ...which isn't so hard.
   316  *
   317  * Setting (channel) to MIX_CHANNEL_POST registers this as a posteffect, and
   318  *  the panning will be done to the final mixed stream before passing it on
   319  *  to the audio device.
   320  *
   321  * This uses the Mix_RegisterEffect() API internally, and returns without
   322  *  registering the effect function if the audio device is not configured
   323  *  for stereo output. Setting both (left) and (right) to 255 causes this
   324  *  effect to be unregistered, since that is the data's normal state.
   325  *
   326  * returns zero if error (no such channel or Mix_RegisterEffect() fails),
   327  *  nonzero if panning effect enabled. Note that an audio device in mono
   328  *  mode is a no-op, but this call will return successful in that case.
   329  *  Error messages can be retrieved from Mix_GetError().
   330  */
   331 extern DECLSPEC int SDLCALL Mix_SetPanning(int channel, Uint8 left, Uint8 right);
   332 
   333 
   334 /* Set the position of a channel. (angle) is an integer from 0 to 360, that
   335  *  specifies the location of the sound in relation to the listener. (angle)
   336  *  will be reduced as neccesary (540 becomes 180 degrees, -100 becomes 260).
   337  *  Angle 0 is due north, and rotates clockwise as the value increases.
   338  *  For efficiency, the precision of this effect may be limited (angles 1
   339  *  through 7 might all produce the same effect, 8 through 15 are equal, etc).
   340  *  (distance) is an integer between 0 and 255 that specifies the space
   341  *  between the sound and the listener. The larger the number, the further
   342  *  away the sound is. Using 255 does not guarantee that the channel will be
   343  *  culled from the mixing process or be completely silent. For efficiency,
   344  *  the precision of this effect may be limited (distance 0 through 5 might
   345  *  all produce the same effect, 6 through 10 are equal, etc). Setting (angle)
   346  *  and (distance) to 0 unregisters this effect, since the data would be
   347  *  unchanged.
   348  *
   349  * If you need more precise positional audio, consider using OpenAL for
   350  *  spatialized effects instead of SDL_mixer. This is only meant to be a
   351  *  basic effect for simple "3D" games.
   352  *
   353  * If the audio device is configured for mono output, then you won't get
   354  *  any effectiveness from the angle; however, distance attenuation on the
   355  *  channel will still occur. While this effect will function with stereo
   356  *  voices, it makes more sense to use voices with only one channel of sound,
   357  *  so when they are mixed through this effect, the positioning will sound
   358  *  correct. You can convert them to mono through SDL before giving them to
   359  *  the mixer in the first place if you like.
   360  *
   361  * Setting (channel) to MIX_CHANNEL_POST registers this as a posteffect, and
   362  *  the positioning will be done to the final mixed stream before passing it
   363  *  on to the audio device.
   364  *
   365  * This is a convenience wrapper over Mix_SetDistance() and Mix_SetPanning().
   366  *
   367  * returns zero if error (no such channel or Mix_RegisterEffect() fails),
   368  *  nonzero if position effect is enabled.
   369  *  Error messages can be retrieved from Mix_GetError().
   370  */
   371 extern DECLSPEC int SDLCALL Mix_SetPosition(int channel, Sint16 angle, Uint8 distance);
   372 
   373 
   374 /* Set the "distance" of a channel. (distance) is an integer from 0 to 255
   375  *  that specifies the location of the sound in relation to the listener.
   376  *  Distance 0 is overlapping the listener, and 255 is as far away as possible
   377  *  A distance of 255 does not guarantee silence; in such a case, you might
   378  *  want to try changing the chunk's volume, or just cull the sample from the
   379  *  mixing process with Mix_HaltChannel().
   380  * For efficiency, the precision of this effect may be limited (distances 1
   381  *  through 7 might all produce the same effect, 8 through 15 are equal, etc).
   382  *  (distance) is an integer between 0 and 255 that specifies the space
   383  *  between the sound and the listener. The larger the number, the further
   384  *  away the sound is.
   385  * Setting (distance) to 0 unregisters this effect, since the data would be
   386  *  unchanged.
   387  * If you need more precise positional audio, consider using OpenAL for
   388  *  spatialized effects instead of SDL_mixer. This is only meant to be a
   389  *  basic effect for simple "3D" games.
   390  *
   391  * Setting (channel) to MIX_CHANNEL_POST registers this as a posteffect, and
   392  *  the distance attenuation will be done to the final mixed stream before
   393  *  passing it on to the audio device.
   394  *
   395  * This uses the Mix_RegisterEffect() API internally.
   396  *
   397  * returns zero if error (no such channel or Mix_RegisterEffect() fails),
   398  *  nonzero if position effect is enabled.
   399  *  Error messages can be retrieved from Mix_GetError().
   400  */
   401 extern DECLSPEC int SDLCALL Mix_SetDistance(int channel, Uint8 distance);
   402 
   403 
   404 /*
   405  * !!! FIXME : Haven't implemented, since the effect goes past the
   406  *              end of the sound buffer. Will have to think about this.
   407  *               --ryan.
   408  */
   409 #if 0
   410 /* Causes an echo effect to be mixed into a sound. (echo) is the amount
   411  *  of echo to mix. 0 is no echo, 255 is infinite (and probably not
   412  *  what you want).
   413  *
   414  * Setting (channel) to MIX_CHANNEL_POST registers this as a posteffect, and
   415  *  the reverbing will be done to the final mixed stream before passing it on
   416  *  to the audio device.
   417  *
   418  * This uses the Mix_RegisterEffect() API internally. If you specify an echo
   419  *  of zero, the effect is unregistered, as the data is already in that state.
   420  *
   421  * returns zero if error (no such channel or Mix_RegisterEffect() fails),
   422  *  nonzero if reversing effect is enabled.
   423  *  Error messages can be retrieved from Mix_GetError().
   424  */
   425 extern no_parse_DECLSPEC int SDLCALL Mix_SetReverb(int channel, Uint8 echo);
   426 #endif
   427 
   428 /* Causes a channel to reverse its stereo. This is handy if the user has his
   429  *  speakers hooked up backwards, or you would like to have a minor bit of
   430  *  psychedelia in your sound code.  :)  Calling this function with (flip)
   431  *  set to non-zero reverses the chunks's usual channels. If (flip) is zero,
   432  *  the effect is unregistered.
   433  *
   434  * This uses the Mix_RegisterEffect() API internally, and thus is probably
   435  *  more CPU intensive than having the user just plug in his speakers
   436  *  correctly. Mix_SetReverseStereo() returns without registering the effect
   437  *  function if the audio device is not configured for stereo output.
   438  *
   439  * If you specify MIX_CHANNEL_POST for (channel), then this the effect is used
   440  *  on the final mixed stream before sending it on to the audio device (a
   441  *  posteffect).
   442  *
   443  * returns zero if error (no such channel or Mix_RegisterEffect() fails),
   444  *  nonzero if reversing effect is enabled. Note that an audio device in mono
   445  *  mode is a no-op, but this call will return successful in that case.
   446  *  Error messages can be retrieved from Mix_GetError().
   447  */
   448 extern DECLSPEC int SDLCALL Mix_SetReverseStereo(int channel, int flip);
   449 
   450 /* end of effects API. --ryan. */
   451 
   452 
   453 /* Reserve the first channels (0 -> n-1) for the application, i.e. don't allocate
   454    them dynamically to the next sample if requested with a -1 value below.
   455    Returns the number of reserved channels.
   456  */
   457 extern DECLSPEC int SDLCALL Mix_ReserveChannels(int num);
   458 
   459 /* Channel grouping functions */
   460 
   461 /* Attach a tag to a channel. A tag can be assigned to several mixer
   462    channels, to form groups of channels.
   463    If 'tag' is -1, the tag is removed (actually -1 is the tag used to
   464    represent the group of all the channels).
   465    Returns true if everything was OK.
   466  */
   467 extern DECLSPEC int SDLCALL Mix_GroupChannel(int which, int tag);
   468 /* Assign several consecutive channels to a group */
   469 extern DECLSPEC int SDLCALL Mix_GroupChannels(int from, int to, int tag);
   470 /* Finds the first available channel in a group of channels,
   471    returning -1 if none are available.
   472  */
   473 extern DECLSPEC int SDLCALL Mix_GroupAvailable(int tag);
   474 /* Returns the number of channels in a group. This is also a subtle
   475    way to get the total number of channels when 'tag' is -1
   476  */
   477 extern DECLSPEC int SDLCALL Mix_GroupCount(int tag);
   478 /* Finds the "oldest" sample playing in a group of channels */
   479 extern DECLSPEC int SDLCALL Mix_GroupOldest(int tag);
   480 /* Finds the "most recent" (i.e. last) sample playing in a group of channels */
   481 extern DECLSPEC int SDLCALL Mix_GroupNewer(int tag);
   482 
   483 /* Play an audio chunk on a specific channel.
   484    If the specified channel is -1, play on the first free channel.
   485    If 'loops' is greater than zero, loop the sound that many times.
   486    If 'loops' is -1, loop inifinitely (~65000 times).
   487    Returns which channel was used to play the sound.
   488 */
   489 #define Mix_PlayChannel(channel,chunk,loops) Mix_PlayChannelTimed(channel,chunk,loops,-1)
   490 /* The same as above, but the sound is played at most 'ticks' milliseconds */
   491 extern DECLSPEC int SDLCALL Mix_PlayChannelTimed(int channel, Mix_Chunk *chunk, int loops, int ticks);
   492 extern DECLSPEC int SDLCALL Mix_PlayMusic(Mix_Music *music, int loops);
   493 
   494 /* Fade in music or a channel over "ms" milliseconds, same semantics as the "Play" functions */
   495 extern DECLSPEC int SDLCALL Mix_FadeInMusic(Mix_Music *music, int loops, int ms);
   496 extern DECLSPEC int SDLCALL Mix_FadeInMusicPos(Mix_Music *music, int loops, int ms, double position);
   497 #define Mix_FadeInChannel(channel,chunk,loops,ms) Mix_FadeInChannelTimed(channel,chunk,loops,ms,-1)
   498 extern DECLSPEC int SDLCALL Mix_FadeInChannelTimed(int channel, Mix_Chunk *chunk, int loops, int ms, int ticks);
   499 
   500 /* Set the volume in the range of 0-128 of a specific channel or chunk.
   501    If the specified channel is -1, set volume for all channels.
   502    Returns the original volume.
   503    If the specified volume is -1, just return the current volume.
   504 */
   505 extern DECLSPEC int SDLCALL Mix_Volume(int channel, int volume);
   506 extern DECLSPEC int SDLCALL Mix_VolumeChunk(Mix_Chunk *chunk, int volume);
   507 extern DECLSPEC int SDLCALL Mix_VolumeMusic(int volume);
   508 
   509 /* Halt playing of a particular channel */
   510 extern DECLSPEC int SDLCALL Mix_HaltChannel(int channel);
   511 extern DECLSPEC int SDLCALL Mix_HaltGroup(int tag);
   512 extern DECLSPEC int SDLCALL Mix_HaltMusic(void);
   513 
   514 /* Change the expiration delay for a particular channel.
   515    The sample will stop playing after the 'ticks' milliseconds have elapsed,
   516    or remove the expiration if 'ticks' is -1
   517 */
   518 extern DECLSPEC int SDLCALL Mix_ExpireChannel(int channel, int ticks);
   519 
   520 /* Halt a channel, fading it out progressively till it's silent
   521    The ms parameter indicates the number of milliseconds the fading
   522    will take.
   523  */
   524 extern DECLSPEC int SDLCALL Mix_FadeOutChannel(int which, int ms);
   525 extern DECLSPEC int SDLCALL Mix_FadeOutGroup(int tag, int ms);
   526 extern DECLSPEC int SDLCALL Mix_FadeOutMusic(int ms);
   527 
   528 /* Query the fading status of a channel */
   529 extern DECLSPEC Mix_Fading SDLCALL Mix_FadingMusic(void);
   530 extern DECLSPEC Mix_Fading SDLCALL Mix_FadingChannel(int which);
   531 
   532 /* Pause/Resume a particular channel */
   533 extern DECLSPEC void SDLCALL Mix_Pause(int channel);
   534 extern DECLSPEC void SDLCALL Mix_Resume(int channel);
   535 extern DECLSPEC int SDLCALL Mix_Paused(int channel);
   536 
   537 /* Pause/Resume the music stream */
   538 extern DECLSPEC void SDLCALL Mix_PauseMusic(void);
   539 extern DECLSPEC void SDLCALL Mix_ResumeMusic(void);
   540 extern DECLSPEC void SDLCALL Mix_RewindMusic(void);
   541 extern DECLSPEC int SDLCALL Mix_PausedMusic(void);
   542 
   543 /* Set the current position in the music stream.
   544    This returns 0 if successful, or -1 if it failed or isn't implemented.
   545    This function is only implemented for MOD music formats (set pattern
   546    order number) and for OGG music (set position in seconds), at the
   547    moment.
   548 */
   549 extern DECLSPEC int SDLCALL Mix_SetMusicPosition(double position);
   550 
   551 /* Check the status of a specific channel.
   552    If the specified channel is -1, check all channels.
   553 */
   554 extern DECLSPEC int SDLCALL Mix_Playing(int channel);
   555 extern DECLSPEC int SDLCALL Mix_PlayingMusic(void);
   556 
   557 /* Stop music and set external music playback command */
   558 extern DECLSPEC int SDLCALL Mix_SetMusicCMD(const char *command);
   559 
   560 /* Synchro value is set by MikMod from modules while playing */
   561 extern DECLSPEC int SDLCALL Mix_SetSynchroValue(int value);
   562 extern DECLSPEC int SDLCALL Mix_GetSynchroValue(void);
   563 
   564 /* Get the Mix_Chunk currently associated with a mixer channel
   565     Returns NULL if it's an invalid channel, or there's no chunk associated.
   566 */
   567 extern DECLSPEC Mix_Chunk * SDLCALL Mix_GetChunk(int channel);
   568 
   569 /* Close the mixer, halting all playing audio */
   570 extern DECLSPEC void SDLCALL Mix_CloseAudio(void);
   571 
   572 /* We'll use SDL for reporting errors */
   573 #define Mix_SetError	SDL_SetError
   574 #define Mix_GetError	SDL_GetError
   575 
   576 /* Ends C function definitions when using C++ */
   577 #ifdef __cplusplus
   578 }
   579 #endif
   580 #include "close_code.h"
   581 
   582 #endif /* _SDL_MIXER_H */