Engine API

The QLC+ engine (engine/src/) provides the core lighting control functionality. This reference documents the primary classes and their APIs.

Doc Class

The Doc class (engine/src/doc.h:54) is the main document that owns and manages all project data.

Constructor

Doc(QObject* parent, int universes = 4);

parent

QObject*

Parent object that owns the Doc instance

universes

int

default:"4"

Number of DMX universes to support

Operating Modes

enum Mode {
    Design  = 0,  // Editing allowed
    Operate = 1   // Running allowed, editing disabled
};

void setMode(Mode mode);
Mode mode() const;

Engine Components

Fixture Management
Function Management
Caches and Components
Groups and Palettes

// Add/remove fixtures
bool addFixture(Fixture* fixture, quint32 id = Fixture::invalidId(),
               bool crossUniverse = false);
bool deleteFixture(quint32 id);
bool replaceFixtures(QList<Fixture*> newFixturesList);

// Access fixtures
Fixture* fixture(quint32 id) const;
QList<Fixture*> const& fixtures() const;
int fixturesCount() const;

// Query fixtures
quint32 fixtureForAddress(quint32 universeAddress) const;
int totalPowerConsumption(int& fuzzy) const;

Signals:

void fixtureAdded(quint32 id);
void fixtureRemoved(quint32 id);
void fixtureChanged(quint32 id);

// Add/remove functions
bool addFunction(Function* function,
                quint32 id = Function::invalidId());
bool deleteFunction(quint32 id);

// Access functions
Function* function(quint32 id) const;
QList<Function*> functions() const;
QList<Function*> functionsByType(Function::Type type) const;
Function* functionByName(QString name);

// Startup function
void setStartupFunction(quint32 id);
quint32 startupFunction();

// Query usage
QList<quint32> getUsage(quint32 functionId);
quint32 nextFunctionID();

Signals:

void functionAdded(quint32 id);
void functionRemoved(quint32 id);
void functionChanged(quint32 id);
void functionNameChanged(quint32 id);

// Get engine components
QLCFixtureDefCache* fixtureDefCache() const;
QLCModifiersCache* modifiersCache() const;
RGBScriptsCache* rgbScriptsCache() const;
IOPluginCache* ioPluginCache() const;
AudioPluginCache* audioPluginCache() const;

// Input/Output
InputOutputMap* inputOutputMap() const;

// Master Timer
MasterTimer* masterTimer() const;

// Audio capture
QSharedPointer<AudioCapture> audioInputCapture() const;
void destroyAudioCapture();

// Clipboard
QLCClipboard* clipboard();

// Monitor properties
MonitorProperties* monitorProperties();

// Fixture groups
bool addFixtureGroup(FixtureGroup* grp,
                    quint32 id = FixtureGroup::invalidId());
bool deleteFixtureGroup(quint32 id);
FixtureGroup* fixtureGroup(quint32 id) const;
QList<FixtureGroup*> fixtureGroups() const;

// Channel groups
bool addChannelsGroup(ChannelsGroup* grp,
                     quint32 id = ChannelsGroup::invalidId());
bool deleteChannelsGroup(quint32 id);
bool moveChannelGroup(quint32 id, int direction);
ChannelsGroup* channelsGroup(quint32 id) const;
QList<ChannelsGroup*> channelsGroups() const;

// Palettes
bool addPalette(QLCPalette* palette,
               quint32 id = QLCPalette::invalidId());
bool deletePalette(quint32 id);
QLCPalette* palette(quint32 id) const;
QList<QLCPalette*> palettes() const;

Load and Save

// Load from XML
bool loadXML(QXmlStreamReader& doc, bool loadIO = true);

// Save to XML
bool saveXML(QXmlStreamWriter* doc);

// Workspace paths
void setWorkspacePath(QString path);
QString workspacePath() const;
QString normalizeComponentPath(const QString& filePath) const;
QString denormalizeComponentPath(const QString& filePath) const;

// Error logging
void appendToErrorLog(QString error);
void clearErrorLog();
QString errorLog();

Modification State

enum LoadStatus { Cleared = 0, Loading, Loaded };

LoadStatus loadStatus() const;
bool isModified() const;
void setModified();
void resetModified();
void clearContents();

Signals:

void modified(bool state);
void needAutosave();
void clearing();
void cleared();
void loading();
void loaded();
void modeChanged(Doc::Mode mode);

Kiosk Mode

void setKiosk(bool kiosk);
bool isKiosk() const;

Fixture Class

The Fixture class (engine/src/fixture.h:71) represents a fixture instance.

Properties

class Fixture final : public QObject
{
    Q_OBJECT
    Q_PROPERTY(quint32 id READ id CONSTANT)
    Q_PROPERTY(QString name READ name WRITE setName NOTIFY changed)
    Q_PROPERTY(int type READ type CONSTANT)
    Q_PROPERTY(quint32 universe READ universe WRITE setUniverse NOTIFY changed)
    Q_PROPERTY(quint32 address READ address WRITE setAddress NOTIFY changed)
    Q_PROPERTY(quint32 channels READ channels WRITE setChannels NOTIFY changed)
};

Identity

// ID management
void setID(quint32 id);
quint32 id() const;
static quint32 invalidId();

// Name
void setName(const QString& name);
QString name() const;

// Type
enum Type {
    Dimmer = 0,
    MovingHead,
    Scanner,
    RGBPanel,
    GenericRGB
};
int type() const;

Addressing

// Universe
void setUniverse(quint32 universe);
quint32 universe() const;

// Address
void setAddress(quint32 address);
quint32 address() const;
quint32 universeAddress() const;  // Combined universe and address

// Channels
void setChannels(quint32 channels);
quint32 channels() const;

Fixture Definition

// Definition and mode
QLCFixtureDef* fixtureDef() const;
QLCFixtureMode* fixtureMode() const;
QString fixtureModeName() const;

// Channels
const QLCChannel* channel(quint32 channel) const;
QLCChannel::Group channelGroup(quint32 channel) const;
uint32_t channelNumber(QLCChannel::Group group,
                      QLCChannel::ControlByte controlByte) const;

Load and Save

bool loadXML(QXmlStreamReader& doc, const QLCFixtureDefCache* fixtureDefCache);
bool saveXML(QXmlStreamWriter* doc) const;

Signals:

void changed(quint32 id);

Function Classes

Base Function Class

All functions inherit from Function (engine/src/function.h:93).

class Function : public QObject
{
    Q_OBJECT
    Q_PROPERTY(QString name READ name WRITE setName NOTIFY nameChanged)
    Q_PROPERTY(quint32 id READ id CONSTANT)
    Q_PROPERTY(Type type READ type CONSTANT)
    Q_PROPERTY(quint32 totalDuration READ totalDuration
               WRITE setTotalDuration NOTIFY totalDurationChanged)
    Q_PROPERTY(RunOrder runOrder READ runOrder WRITE setRunOrder
               NOTIFY runOrderChanged)
};

Function Types

enum Type {
    Undefined      = 0,
    SceneType      = 1 << 0,
    ChaserType     = 1 << 1,
    EFXType        = 1 << 2,
    CollectionType = 1 << 3,
    ScriptType     = 1 << 4,
    RGBMatrixType  = 1 << 5,
    ShowType       = 1 << 6,
    SequenceType   = 1 << 7,
    AudioType      = 1 << 8,
    VideoType      = 1 << 9
};

Core Methods

// Identity
void setID(quint32 id);
quint32 id() const;
static quint32 invalidId();

void setName(const QString& name);
QString name() const;

Type type() const;

// Duration
void setTotalDuration(uint ms);
uint totalDuration() const;
uint elapsed() const;

// Timing
void setFadeInSpeed(uint ms);
uint fadeInSpeed() const;
void setFadeOutSpeed(uint ms);
uint fadeOutSpeed() const;
void setDuration(uint ms);
uint duration() const;

Playback Control

enum Direction { Forward, Backward };
enum RunOrder { Loop, SingleShot, PingPong, Random };
enum TempoType { Time, Beats };

void setDirection(Direction dir);
Direction direction() const;

void setRunOrder(RunOrder order);
RunOrder runOrder() const;

void setTempoType(TempoType type);
TempoType tempoType() const;

// Running
virtual void start(MasterTimer* timer, FunctionParent* parent);
virtual void stop(FunctionParent* parent);
virtual void stopAndWait();
virtual bool isRunning() const;
virtual bool isPaused() const;
virtual void togglePause();

Execution

// Called by MasterTimer
virtual void write(MasterTimer* timer, QList<Universe*> universes);
virtual void postRun(MasterTimer* timer, QList<Universe*> universes);

Attributes

// Get/set function attributes
QVariant attributeValue(int attrIndex) const;
void setAttributeValue(int attrIndex, qreal value);
void adjustAttribute(qreal fraction, int attrIndex = Function::Intensity);

QList<Attribute> attributes() const;
QList<AttributeOverride> attributeOverrides() const;

Signals:

void changed(quint32 id);
void nameChanged(quint32 id);
void running(quint32 id);
void stopped(quint32 id);
void totalDurationChanged();
void attributeChanged(int attrIndex, qreal fraction);

InputOutputMap Class

Manages DMX universes and I/O plugin mapping.

class InputOutputMap : public QObject
{
public:
    // Universe management
    quint32 universes() const;
    void setUniverseCount(quint32 count);
    
    // Plugin management
    IOPluginCache* pluginCache();
    QStringList pluginNames() const;
    
    // Patching
    bool setInputPatch(quint32 universe, const QString& pluginName,
                      quint32 input, const QString& profileName = QString());
    bool setOutputPatch(quint32 universe, const QString& pluginName,
                       quint32 output);
    
    InputPatch* inputPatch(quint32 universe) const;
    OutputPatch* outputPatch(quint32 universe) const;
    
    // DMX I/O
    void setUniverseValue(quint32 universe, quint32 channel, uchar value);
    uchar getUniverseValue(quint32 universe, quint32 channel) const;
    
    // Grand Master
    GrandMaster* grandMaster() const;
    
signals:
    void inputValueChanged(quint32 universe, quint32 channel, uchar value);
    void universeWritten(quint32 universe, const QByteArray& data);
    void pluginConfigurationChanged(const QString& pluginName);
};

MasterTimer Class

The real-time engine that executes functions.

class MasterTimer : public QObject
{
public:
    // Start/stop timer
    void start();
    void stop();
    bool isRunning() const;
    
    // Frequency
    void setFrequency(uint freq);
    uint frequency() const;
    
    // Function control
    void startFunction(Function* function, bool initiatedByOtherFunction = false);
    void stopFunction(Function* function, bool initiatedByOtherFunction = false);
    void stopAllFunctions();
    QList<Function*> runningFunctions() const;
    
    // Time
    quint32 tick() const;
    quint32 runningFunctionsCount() const;
    
signals:
    void functionListChanged();
};

Universe Data Types

// Channel data
typedef uchar ChannelValue;  // 0-255

// Universe size
#define UNIVERSE_SIZE 512

// Combined universe and address
inline quint32 universeAddress(quint32 universe, quint32 address) {
    return (universe << 9) | address;
}

inline quint32 extractUniverse(quint32 universeAddress) {
    return universeAddress >> 9;
}

inline quint32 extractAddress(quint32 universeAddress) {
    return universeAddress & 0x1FF;
}

Working with the Engine

Creating a Doc Instance

// Create document with 4 universes
Doc* doc = new Doc(this, 4);

// Load fixture definitions
doc->fixtureDefCache()->load("path/to/fixtures");

// Set up I/O
InputOutputMap* ioMap = doc->inputOutputMap();
ioMap->setOutputPatch(0, "Art-Net", 0);

Adding Fixtures

// Create fixture
Fixture* fixture = new Fixture(doc);
fixture->setName("My Moving Head");
fixture->setUniverse(0);
fixture->setAddress(0);
fixture->setChannels(16);

// Add to document
doc->addFixture(fixture);

Creating Functions

// Create scene
Scene* scene = new Scene(doc);
scene->setName("Red Wash");
scene->setValue(fixtureId, 0, 255);  // Set channel 0 to 255

// Add to document
doc->addFunction(scene);

// Start function
MasterTimer* timer = doc->masterTimer();
timer->startFunction(scene);

Monitoring Changes

// Connect to signals
connect(doc, &Doc::fixtureAdded,
        this, &MyClass::onFixtureAdded);
connect(doc, &Doc::functionChanged,
        this, &MyClass::onFunctionChanged);
connect(doc, &Doc::modified,
        this, &MyClass::onDocModified);

Thread Safety

The MasterTimer runs in its own thread. Function write() methods are called from this thread.

Safe Practices

class MyFunction : public Function
{
private:
    QMutex m_mutex;  // Protect shared data
    
public:
    void write(MasterTimer* timer, QList<Universe*> universes) override
    {
        QMutexLocker locker(&m_mutex);
        // Safe access to shared data
    }
    
    void setProperty(int value)
    {
        QMutexLocker locker(&m_mutex);
        m_property = value;
    }
};

Building & Contributing

API Reference

Fixture Development

Doc Class

Constructor

Operating Modes

Engine Components

Load and Save

Modification State

Kiosk Mode

Fixture Class

Properties

Identity

Addressing

Fixture Definition

Load and Save

Function Classes

Base Function Class

Function Types

Core Methods

Playback Control

Execution

Attributes

InputOutputMap Class

MasterTimer Class

Universe Data Types

Working with the Engine

Creating a Doc Instance

Adding Fixtures

Creating Functions

Monitoring Changes

Thread Safety

Safe Practices

Resources

Build docs developers (and LLMs) love

Building & Contributing

API Reference

Fixture Development

​Doc Class

​Constructor

​Operating Modes

​Engine Components

​Load and Save

​Modification State

​Kiosk Mode

​Fixture Class

​Properties

​Identity

​Addressing

​Fixture Definition

​Load and Save

​Function Classes

​Base Function Class

​Function Types

​Core Methods

​Playback Control

​Execution

​Attributes

​InputOutputMap Class

​MasterTimer Class

​Universe Data Types

​Working with the Engine

​Creating a Doc Instance

​Adding Fixtures

​Creating Functions

​Monitoring Changes

​Thread Safety

​Safe Practices

​Resources

Build docs developers (and LLMs) love

Doc Class

Constructor

Operating Modes

Engine Components

Load and Save

Modification State

Kiosk Mode

Fixture Class

Properties

Identity

Addressing

Fixture Definition

Load and Save

Function Classes

Base Function Class

Function Types

Core Methods

Playback Control

Execution

Attributes

InputOutputMap Class

MasterTimer Class

Universe Data Types

Working with the Engine

Creating a Doc Instance

Adding Fixtures

Creating Functions

Monitoring Changes

Thread Safety

Safe Practices

Resources