XYSeriesIODevice Class Reference

A specialized I/O device that bridges raw signal data to the audio hardware. More...

#include <xyseriesiodevice.h>

Inheritance diagram for XYSeriesIODevice:

Public Types
enum class	PlayMode { Waveform , WavFile }
	Operational states for the audio engine. More...

Public Member Functions
	XYSeriesIODevice (QObject *parent=nullptr)
	Constructs the I/O device.
virtual	~XYSeriesIODevice ()=default
	Virtual destructor. Explicitly defaulted to ensure safe polymorphic deletion of derived classes.
	XYSeriesIODevice (const XYSeriesIODevice &)=delete
	Deleted copy constructor to prevent accidental duplication of the audio stream.
XYSeriesIODevice &	operator= (const XYSeriesIODevice &)=delete
	Deleted assignment operator to enforce unique ownership of the I/O state.
void	updateTable (const std::vector< float > &data)
	Loads new PCM data into the internal lookup table.
void	setFrequency (float hz)
	Sets the fundamental frequency for the Waveform synthesis mode.
qint64	readData (char *data, qint64 maxlen) override
	Core audio callback used by the Qt Audio engine.
qint64	writeData (const char *, qint64) override
	Placeholder for write operations; always returns 0.
bool	isSequential () const override
	Indicates that this is a continuous audio stream.
void	setPlayMode (PlayMode mode)
	Toggles between the available playback engines.
PlayMode	getPlayMode () const
	Returns the current playback mode.
float	getCurrentPhase () const
	Returns the current oscillator phase [0, tableSize].
qint64	getCurrentWavIndex () const
	Returns the current sample index in WavFile mode.

Private Attributes
PlayMode	m_currentMode = PlayMode::Waveform
std::vector< float >	m_table
float	m_phase {0.0f}
qint64	m_wavIndex {0}
float	m_increment {0.0f}
const float	m_sampleRate {44100.0f}

Detailed Description

A specialized I/O device that bridges raw signal data to the audio hardware.

This class implements a real-time playback engine designed for the PS-80 GrandComp. It manages two distinct operational modes: periodic waveform synthesis (oscillation) and linear WAV file streaming.

Member Enumeration Documentation

PlayMode

enum class XYSeriesIODevice::PlayMode

strong

Operational states for the audio engine.

Enumerator
Waveform	Oscillator mode: Loops the extracted single-cycle.
WavFile	1:1 Playback mode: Streams the original source data.

Constructor & Destructor Documentation

XYSeriesIODevice() [1/2]

XYSeriesIODevice::XYSeriesIODevice ( QObject * parent = nullptr )

explicit

Constructs the I/O device.

Constructs the device and prepares the I/O interface.

Parameters

parent

Parent QObject.

• The device is opened in ReadOnly mode to interface with the Qt Audio output.

~XYSeriesIODevice()

virtual XYSeriesIODevice::~XYSeriesIODevice ( )

virtualdefault

Virtual destructor. Explicitly defaulted to ensure safe polymorphic deletion of derived classes.

XYSeriesIODevice() [2/2]

XYSeriesIODevice::XYSeriesIODevice ( const XYSeriesIODevice & )

delete

Deleted copy constructor to prevent accidental duplication of the audio stream.

Member Function Documentation

getCurrentPhase()

float XYSeriesIODevice::getCurrentPhase ( ) const

inline

Returns the current oscillator phase [0, tableSize].

getCurrentWavIndex()

qint64 XYSeriesIODevice::getCurrentWavIndex ( ) const

inline

Returns the current sample index in WavFile mode.

getPlayMode()

PlayMode XYSeriesIODevice::getPlayMode ( ) const

inline

Returns the current playback mode.

isSequential()

bool XYSeriesIODevice::isSequential ( ) const

inlineoverride

Indicates that this is a continuous audio stream.

operator=()

XYSeriesIODevice & XYSeriesIODevice::operator= ( const XYSeriesIODevice & )

delete

Deleted assignment operator to enforce unique ownership of the I/O state.

readData()

qint64 XYSeriesIODevice::readData ( char * data, qint64 maxlen )

override

Core audio callback used by the Qt Audio engine.

Real-time audio processing loop.

• Reads PCM data from the internal buffer based on the active PlayMode. In Waveform mode, it utilizes phase accumulation to loop the cycle.

• Parameters

  data	Destination buffer for the audio samples.
  maxlen	Maximum number of bytes to read.

  Returns

  qint64 Number of bytes actually read.

• Depending on the active PlayMode, this function either synthesizes a periodic waveform using linear interpolation or streams raw data.

1. Periodic Synthesis (Oscillator) Uses linear interpolation between samples to maintain signal integrity at non-integer phase positions.

1. Linear Playback (WAV Audit) Streams the buffer 1:1. m_wavIndex tracks the position.

setFrequency()

void XYSeriesIODevice::setFrequency

(

float

hz

)

Sets the fundamental frequency for the Waveform synthesis mode.

Calculates the phase increment based on a target frequency.

Parameters

hz	Target frequency in Hertz (e.g., 55.0 for A1).

• Formula: increment = (Frequency * TableSize) / SampleRate. This ensures pitch accuracy in PlayMode::Waveform.

setPlayMode()

void XYSeriesIODevice::setPlayMode

(

PlayMode

mode

)

Toggles between the available playback engines.

Changes the playback engine state and resets indices.

Parameters

mode	The desired PlayMode.

• Parameters

  mode	The new PlayMode to be used in readData.

updateTable()

void XYSeriesIODevice::updateTable

(

const std::vector< float > &

data

)

Loads new PCM data into the internal lookup table.

Updates the internal signal buffer.

Parameters

data	A vector of floating-point samples normalized to [-1.0, 1.0].
data	PCM samples used for both synthesis and linear playback.

writeData()

qint64 XYSeriesIODevice::writeData ( const char * , qint64  )

inlineoverride

Placeholder for write operations; always returns 0.

Field Documentation

m_currentMode

PlayMode XYSeriesIODevice::m_currentMode = PlayMode::Waveform

private

Current engine state.

m_increment

float XYSeriesIODevice::m_increment {0.0f}

private

Phase step per sample, derived from frequency.

m_phase

float XYSeriesIODevice::m_phase {0.0f}

private

Phase accumulator for Waveform mode.

m_sampleRate

const float XYSeriesIODevice::m_sampleRate {44100.0f}

private

System sample rate for time-base calculations.

m_table

std::vector<float> XYSeriesIODevice::m_table

private

Internal buffer for PCM signal data.

m_wavIndex

qint64 XYSeriesIODevice::m_wavIndex {0}

private

Current read pointer for WavFile mode.

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

• xyseriesiodevice.h
• xyseriesiodevice.cpp