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AudioToFile Class Reference

Mixes each active channel and writes it to a file descriptor. More...

#include <AudioToFile.h>

Inheritance diagram for AudioToFile

[legend]Collaboration diagram for AudioToFile:

[legend]List of all members.

Public Methods
	AudioToFile (bool threaded = true)
virtual	~AudioToFile ()
virtual Result	Play (Sample& sample)
	play the sample, without waiting for it to finish.
virtual Result	PlayNoWait (Sample& sample, int& NewChanelID, int& NewVoice)
	Play the sample and return without waiting for it to finish.
virtual Result	WaitForVoiceToFinish (int voice, int ChannelID)
	do as it says.
virtual int	AllocateVoice (const Sample& sample, int voice = -1)
	Allocates a voice for a sound which will be mixed into the buffer. More...
virtual Result	DeleteVoice (int voice)
	Remove the given voice from the Audio manager.
virtual Channel*	AllocateChannel ()
	Create a new Channel.
virtual void	DeleteChannel (Channel*& channel)
	Delete the given Channel.
virtual int	VoicesAllocated () const
	Return the number of current voices allocated.
virtual Result	SetLocation (int x, int y, int z, int channel)
virtual Result	SetX (int x, int channel)
virtual Result	SetY (int y, int channel)
virtual Result	SetZ (int z, int channel)
virtual Result	GetLocation (int& x, int& y, int& z, int channel)
virtual Result	GetX (int& x, int channel)
virtual Result	GetY (int& y, int channel)
virtual Result	GetZ (int& z, int channel)
virtual Result	SetVolume (Volume volume, int channel)
	volume.
virtual Volume	GetVolume (int channel)
virtual Result	SetVelocity (Velocity velocity, int channel)
	velocity -- how hard the key was pressed -- is this useful?
virtual Velocity	GetVelocity (int channel)
virtual Result	SetFrequency (Frequency frequency, int channel)
	frequency.
virtual Frequency	GetFrequency (int channel)
virtual Result	SetPosition (unsigned long position, int channel)
	position.
unsigned long	GetPosition (int channel)
virtual Result	SetVoice (int voice, int channel)
	Set the voice for the given channel.
virtual int	GetVoice (int channel)
	get the voice that has been assigned to the channel.
virtual int	NextChannel ()
	return the channel id for the next channel.
virtual void	Start (int channel)
	Start the playback sample mixing thread if it hasn't already been started and enable the channel for mixing. We have two options for the mixer. Either fork a new process and communicate via a pipe or perhaps shared memory, or start a new thread for the mixer. Some libraries are not thread safe so it may be a good idea to fork a process for the mixer.
virtual void	Stop (int channel)
	Stop the channel from making any noise.
virtual long	GetPlaybackRate ()
virtual void	SetTimeout (long milliseconds)
virtual void	StartTimeout ()
virtual void	StopTimeout ()
virtual void	WaitForTimeout ()
virtual Result	StreamBuffer (const unsigned char* buffer, unsigned long length, int bits = 16, int channels = 2)
	experimental and untested.
virtual Result	StreamBuffer (const short* buffer, unsigned long length, int channels, Filters::SimpleFilter<short>& filter)
virtual bool	IsStreamable () const
Protected Types
typedef ThreadV<class AudioToFile>	MixerThreadV
typedef MapLikeContainer<Status, 128>	ChannelContainer
typedef MapLikeContainer<const Sample*, 128>	VoiceContainer
Protected Methods
virtual void	PrepareBuffer ()
	Prepare the buffer for mixing. More...
virtual void	Output (int x)
	Write the samples to the output using the correct output function for the sample type.
virtual int	WriteData (unsigned char* buffer, size_t length)
virtual void	MixBuffer (Status& status, unsigned long length)
	Parameters: status   The Status of the channel that is being mixed. length   The length of data to mix.
void	MixerThread ()
	This thread mixes all the active channels together and writes the result to the audio device file.
bool	Mix ()
	Enumate the channels, mix the samples in each channel, and write the result to the file descriptor using Output(). More...
void	MixChannel ( Status& status )
	Mix a channel. More...
void	MixLoopedChannel ( Status& status )
	Parameters: status.
void	MixOneShotChannel ( Status& status )
	Parameters: status   The Status of the channel being mixed.
void	MixTinyLoop (Status& status, unsigned long& playlength)
bool	KeepMixing ()
void	Output32_16stereo (int x)
	Convert the audio buffer from 32 bit stereo to 16 bit stereo.
void	Output32_16mono (int x)
	Convert the audio buffer from 32 stereo to 16 bit mono.
void	Output32_8stereo (int x)
void	Output32_8mono (int x)
bool	TryToOutput (int x)
void	Run ()
Protected Attributes
MixerThreadV*	m_mixer_thread
Mutex	m_mutex
bool	m_use_threads
Timeout*	m_timeout
ChannelContainer	m_channels
VoiceContainer	m_voices
long	m_milliseconds
long	m_mix_length
	number of samples to mix.
unsigned long	m_buffer_size
	size in bytes.
unsigned char*	m_audio_buffer [2]
bool	m_dirty [2]
int	m_current_mix_buffer
int	m_current_output_buffer
int	m_channels_enabled
int	m_fd
int	m_bits
int	m_rate
bool	m_stereo
bool	m_mixer_started
Static Protected Methods
void	StreamBufferCallback (Status* status, void* data)
void*	thread_callback (void* me)
	This function is given to pthread_create as the callback. It must be static, otherwise the hidden "this" pointer will get corrupted. The argument given in me should be the "this" pointer so that we can get back inside the class again.
Static Protected Attributes
const int	DEFAULT_BUFFER_SIZE = 8192
Friends
class	ThreadV< class AudioToFile >

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Detailed Description

Mixes each active channel and writes it to a file descriptor.

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Member Function Documentation

int AudioToFile::AllocateVoice ( const Sample & sample, int voice = -1 ) [virtual]

Allocates a voice for a sound which will be mixed into the buffer. It returns number corresponding to it's place in the array of samples (voices.) this should make a copy of the sample structure or at least not rely on the reference to Sample given always being valid it will assign the voice to the number "voice" or if voice is -1 then it will get the next free voice number and return it. Reimplemented from Audio.

bool AudioToFile::KeepMixing ( ) [inline, protected]

Returns: True if there is still a channel enabled.

bool AudioToFile::Mix ( ) [inline, protected]

Enumate the channels, mix the samples in each channel, and write the result to the file descriptor using Output(). If the file was not yet ready to be written to then the samples will have been mixed but not output and false will be returned. The next time Mix() is called the samples that were mixed but not output will be written

void AudioToFile::MixChannel ( Status & status ) [protected]

Mix a channel. Parameters: status   The Status of the channel that is being mixed.

void AudioToFile::PrepareBuffer ( ) [inline, protected, virtual]

Prepare the buffer for mixing. Simply zeros the buffer. Reimplemented in DspMmapped.

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

• /home/pcburns/c/penguinsound/include/PenguinSound/AudioToFile.h
• /home/pcburns/c/penguinsound/src/PenguinSound/AudioToFile.cpp

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