WAVFile Class Reference

A wrapper for opening and playing a WAV file using SDL. More...

#include <sdlwavfile.h>

Collaboration diagram for WAVFile:

[legend]List of all members.

Public Member Functions
	WAVFile (const std::string &file, int volume=SDL_MIX_MAXVOLUME)
	Constructor will load the wav file from disk into sound and initialise the data members.
	~WAVFile ()
	Destructor will free the memory used by the sound buffer.
void	setVolume (int newVol=SDL_MIX_MAXVOLUME)
	Change the volume.
void	play (bool repeat=false)
	Commence playing this WAV file on the audio stream.
void	open ()
	Open a connection to the audio device - only one WAVFile can be connected at once (the most recent connection will preempt any others).
void	stop ()
	Stop playing this WAVFile and close all connections to the audio device.
void	pause ()
	Pause the playing of all WAVFile s (so that they may subsequently be resumed() d.
void	resume ()
	Restart the playing of the WAVFile currently connected to the audio device.
Protected Member Functions
void	fill (Uint8 *stream, int len)
	SDL will [indirectly] call this to fill its audio buffer, and this function will then fill it.
void	lock ()
	Increment the synchronised function call depth, locking if it is the first.
void	unlock ()
	Decrement the synchronised function call depth, unlocking if it is the last.
Protected Attributes
SDL_AudioSpec	spec
	SDL Specification for the WAV.
Uint8 *	sound
	The (entire) WAV file, buffered.
Uint32	slen
	The length of the WAV file buffer.
int	spos
	The current pointer offset in sound.
bool	once
	if false, the playing will repeat/loop
bool	nomore
	if true, the next fill() will call stop()
int	vol
	The current volume in [0, SDL_MIX_MAXVOLUME].
int	locks
	The number of locks (synchronised fn call depth).
Private Member Functions
	WAVFile (const WAVFile &)
	No copying.
Friends
void	fillerup (void *, Uint8 *, int)
	Callback for when the SDL Audio device needs more data.

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Detailed Description

A wrapper for opening and playing a WAV file using SDL.

Any number of WAVFile s may be created, for any number (or the same) WAV files. However, only one can be playing at once (this is a limitation of SDL). When another file starts playing - playback of the other WAV will be stopped. To resume, it must be play() ed again.

Examples:

sdlplay.cc.

Definition at line 34 of file sdlwavfile.h.

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Constructor & Destructor Documentation

WAVFile::WAVFile (  const WAVFile &   )  [private]

No copying.

WAVFile::WAVFile (  const std::string &  file, int  volume = SDL_MIX_MAXVOLUME )

Constructor will load the wav file from disk into sound and initialise the data members. Parameters: file  The wav file to load volume  The initial volume to use Exceptions: SoundException  if SDL could not load the wav file Definition at line 47 of file sdlwavfile.cc. References SDL_AudioSpec::callback, fillerup(), lock(), SDL_LoadWAV, setVolume(), slen, sound, spec, unlock(), and SDL_AudioSpec::userdata.

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WAVFile::~WAVFile (   )

Destructor will free the memory used by the sound buffer. Definition at line 106 of file sdlwavfile.cc. References lock(), SDL_FreeWAV(), sound, and unlock().

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Member Function Documentation

void WAVFile::fill (  Uint8 *  stream, int  len )  [protected]

SDL will [indirectly] call this to fill its audio buffer, and this function will then fill it. Parameters: stream  SDL's audio buffer to fill len  the length of the buffer Definition at line 76 of file sdlwavfile.cc. References nomore, once, SDL_MixAudio(), slen, sound, spos, stop(), and vol.

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void WAVFile::lock (   )  [protected]

Increment the synchronised function call depth, locking if it is the first. Definition at line 63 of file sdlwavfile.cc. References locks, and SDL_LockAudio(). Referenced by open(), pause(), play(), resume(), stop(), WAVFile(), and ~WAVFile().

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void WAVFile::open (   )

Open a connection to the audio device - only one WAVFile can be connected at once (the most recent connection will preempt any others). This can be used to resume a file, if it was interrupted by playing another wav, otherwise just play() works. Exceptions: SoundException  if the connection failed Definition at line 124 of file sdlwavfile.cc. References lock(), SDL_OpenAudio(), spec, stop(), and unlock(). Referenced by play().

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void WAVFile::pause (   )

Pause the playing of all WAVFile s (so that they may subsequently be resumed() d. Examples: sdlplay.cc. Definition at line 142 of file sdlwavfile.cc. References lock(), SDL_PauseAudio(), and unlock().

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void WAVFile::play (  bool  repeat = false  )

Commence playing this WAV file on the audio stream. Parameters: repeat  if true, the playing will loop indefinitely until a stop() [or pause()] Examples: sdlplay.cc. Definition at line 116 of file sdlwavfile.cc. References lock(), once, open(), resume(), and unlock().

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void WAVFile::resume (   )

Restart the playing of the WAVFile currently connected to the audio device. Examples: sdlplay.cc. Definition at line 148 of file sdlwavfile.cc. References lock(), SDL_PauseAudio(), and unlock(). Referenced by play().

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void WAVFile::setVolume (  int  newVol = SDL_MIX_MAXVOLUME  )

Change the volume. Parameters: newVol  the new volume - will be clipped to the range [0, SDL_MIX_MAXVOLUME] Examples: sdlplay.cc. Definition at line 112 of file sdlwavfile.cc. References SDL_MIX_MAXVOLUME, and vol. Referenced by WAVFile().

void WAVFile::stop (   )

Stop playing this WAVFile and close all connections to the audio device. Examples: sdlplay.cc. Definition at line 134 of file sdlwavfile.cc. References lock(), nomore, SDL_CloseAudio(), spos, and unlock(). Referenced by fill(), and open().

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void WAVFile::unlock (   )  [protected]

Decrement the synchronised function call depth, unlocking if it is the last. Definition at line 69 of file sdlwavfile.cc. References locks, and SDL_UnlockAudio(). Referenced by open(), pause(), play(), resume(), stop(), WAVFile(), and ~WAVFile().

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Friends And Related Function Documentation

void fillerup (  void *  wavfile, Uint8 *  stream, int  len )  [friend]

Callback for when the SDL Audio device needs more data. This is called by SDL automatically. Definition at line 43 of file sdlwavfile.cc.

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Member Data Documentation

int WAVFile::locks [protected]

The number of locks (synchronised fn call depth). Definition at line 46 of file sdlwavfile.h. Referenced by lock(), and unlock().

bool WAVFile::nomore [protected]

if true, the next fill() will call stop() Definition at line 44 of file sdlwavfile.h. Referenced by fill(), and stop().

bool WAVFile::once [protected]

if false, the playing will repeat/loop Definition at line 43 of file sdlwavfile.h. Referenced by fill(), and play().

Uint32 WAVFile::slen [protected]

The length of the WAV file buffer. Definition at line 41 of file sdlwavfile.h. Referenced by fill(), and WAVFile().

Uint8* WAVFile::sound [protected]

The (entire) WAV file, buffered. Definition at line 40 of file sdlwavfile.h. Referenced by fill(), WAVFile(), and ~WAVFile().

SDL_AudioSpec WAVFile::spec [protected]

SDL Specification for the WAV. Definition at line 39 of file sdlwavfile.h. Referenced by open(), and WAVFile().

int WAVFile::spos [protected]

The current pointer offset in sound. Definition at line 42 of file sdlwavfile.h. Referenced by fill(), and stop().

int WAVFile::vol [protected]

The current volume in [0, SDL_MIX_MAXVOLUME]. Definition at line 45 of file sdlwavfile.h. Referenced by fill(), and setVolume().

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The documentation for this class was generated from the following files:

• sdlwavfile.h
• sdlwavfile.cc

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