DeviceAudioRt Class Reference

an rtAudio based stereo audio mixer/playback device More...

#include <proAudioRt.h>

Inheritance diagram for DeviceAudioRt:


Public Member Functions
virtual unsigned int	sampleFromMemory (const AudioSample &sample, float volume=1.0f)
virtual bool	sampleDestroy (unsigned int sample)
virtual const AudioSample *	sample (unsigned int handle) const
virtual unsigned int	soundPlay (unsigned int sample, float volumeL=1.0f, float volumeR=1.0f, float disparity=0.0f, float pitch=1.0f)
virtual unsigned int	soundLoop (unsigned int sample, float volumeL=1.0f, float volumeR=1.0f, float disparity=0.0f, float pitch=1.0f)
virtual bool	soundUpdate (unsigned int sound, float volumeL, float volumeR, float disparity=0.0f, float pitch=1.0f)
virtual bool	soundStop (unsigned int sound)
virtual void	soundStop ()
virtual unsigned	soundActive () const
Static Public Member Functions
static DeviceAudio *	create (unsigned int nTracks=8, unsigned int frequency=22050, unsigned int chunkSize=1024)
Protected Member Functions
	DeviceAudioRt (unsigned int nTracks, unsigned int frequency, unsigned int chunkSize)
virtual	~DeviceAudioRt ()
int	mixOutputFloat (signed short *outputBuffer, unsigned int nFrames)
Static Protected Member Functions
static int	cbMix (void outputBuffer, void inputBuffer, unsigned int nFrames, double streamTime, RtAudioStreamStatus status, void *data)
Protected Attributes
std::map< unsigned int, AudioSample * >	mm_sample
unsigned int	m_sampleCounter
_AudioTrack *	ma_sound
unsigned int	m_nSound
RtAudio	m_dac

Detailed Description

an rtAudio based stereo audio mixer/playback device

DeviceAudioRt offers some advanced features such as dynamic pitch, independent volume control for both channels, and user-defined time shifts between the channels.

Constructor & Destructor Documentation

DeviceAudioRt::DeviceAudioRt ( unsigned int nTracks,

unsigned int frequency,

unsigned int chunkSize

) [protected]

constructor. Use the create() method instead

virtual DeviceAudioRt::~DeviceAudioRt ( ) [protected, virtual]

destructor. Use the destroy() method instead

Member Function Documentation

static int DeviceAudioRt::cbMix ( void * outputBuffer,

void * inputBuffer,

unsigned int nFrames,

double streamTime,

RtAudioStreamStatus status,

void * data

) [inline, static, protected]

mixer callback

static DeviceAudio* DeviceAudioRt::create ( unsigned int nTracks = 8,

unsigned int frequency = 22050,

unsigned int chunkSize = 1024

) [static]

creates audio device
Use this method instead of a constructor.
Parameters:

nTracks (optional) the maximum number of sounds that are played parallely. Computation time is linearly correlated to this factor.

frequency (optional) sample frequency of the playback in Hz. 22050 corresponds to FM radio 44100 is CD quality. Computation time is linearly correlated to this factor.

chunkSize (optional) the number of bytes that are sent to the sound card at once. Low numbers lead to smaller latencies but need more computation time (thread switches). If a too small number is chosen, the sounds might not be played continuously. The default value 512 guarantees a good latency below 40 ms at 22050 Hz sample frequency.

Returns:
a pointer to an audio device object in case of success Note that the parameters are only handled when calling for the first time. Afterwards always the same object is returned until an explicit destroy() is called.

int DeviceAudioRt::mixOutputFloat ( signed short * outputBuffer,

unsigned int nFrames

) [protected]

mixes tracks to a single output stream

virtual const AudioSample* DeviceAudioRt::sample ( unsigned int handle ) const [virtual]

allows read access to a sample identified by its handle

Reimplemented from DeviceAudio.

virtual bool DeviceAudioRt::sampleDestroy ( unsigned int sample ) [virtual]

deletes a previously created sound sample resource identified by its handle

Implements DeviceAudio.

virtual unsigned int DeviceAudioRt::sampleFromMemory ( const AudioSample & sample,

float volume = 1.0f

) [virtual]

converts a sound sample to internal audio format, returns handle

Implements DeviceAudio.

virtual unsigned DeviceAudioRt::soundActive ( ) const [virtual]

returns number of currently active sounds

Implements DeviceAudio.

virtual unsigned int DeviceAudioRt::soundLoop ( unsigned int sample,

float volumeL = 1.0f,

float volumeR = 1.0f,

float disparity = 0.0f,

float pitch = 1.0f

) [virtual]

plays a specified sample continuously and sets its parameters
Parameters:

sample a sample handle returned by a previous load() call

volumeL (optional) left volume

volumeR (optional) right volume

disparity (optional) time difference between left and right channel in seconds. Use negative values to specify a delay for the left channel, positive for the right.

pitch (optional) pitch factor for playback. 0.5 corresponds to one octave below, 2.0 to one above the original sample.

Returns:
a handle to the currently played sound or 0 in case of error

Implements DeviceAudio.

virtual unsigned int DeviceAudioRt::soundPlay ( unsigned int sample,

float volumeL = 1.0f,

float volumeR = 1.0f,

float disparity = 0.0f,

float pitch = 1.0f

) [virtual]

plays a specified sample once and sets its parameters

Parameters:

sample a sample handle returned by a previous load() call

volumeL (optional) left volume

volumeR (optional) right volume

disparity (optional) time difference between left and right channel in seconds. Use negative values to specify a delay for the left channel, positive for the right.

pitch (optional) pitch factor for playback. 0.5 corresponds to one octave below, 2.0 to one above the original sample.

Returns:
a handle to the currently played sound or 0 in case of error

Implements DeviceAudio.

virtual void DeviceAudioRt::soundStop ( ) [virtual]

stops all sounds immediately

Implements DeviceAudio.

virtual bool DeviceAudioRt::soundStop ( unsigned int sound ) [virtual]

stops a specified sound immediately

Implements DeviceAudio.

virtual bool DeviceAudioRt::soundUpdate ( unsigned int sound,

float volumeL,

float volumeR,

float disparity = 0.0f,

float pitch = 1.0f

) [virtual]

updates parameters of a specified sound

Parameters:

sound handle of a currently active sound

volumeL left volume

volumeR right volume

disparity (optional) time difference between left and right channel in seconds. Use negative values to specify a delay for the left channel, positive for the right.

pitch (optional) pitch factor for playback. 0.5 corresponds to one octave below, 2.0 to one above the original sample.

Returns:
true in case the parameters have been updated successfully

Implements DeviceAudio.

Member Data Documentation

RtAudio DeviceAudioRt::m_dac [protected]

audio manager

unsigned int DeviceAudioRt::m_nSound [protected]

stores number of parallel sounds

unsigned int DeviceAudioRt::m_sampleCounter [protected]

stores maximum sample id

_AudioTrack* DeviceAudioRt::ma_sound [protected]

stores sounds to be mixed

std::map<unsigned int, AudioSample*> DeviceAudioRt::mm_sample [protected]

stores loaded sound samples

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

proAudioRt.h

impressum

DeviceAudioRt Class Reference

Public Member Functions

Static Public Member Functions

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation