Holds data for a single curve. More...

#include <plotinstance.h>

Public Types
enum	Flag { DataComplete = (1 << 0), RingBuffer = (1 << 1), ExplicitColour = (1 << 2), FilterNaN = (1 << 3), FilterInf = (1 << 4), ExplicitTime = (1 << 5) }
	Status, control and display flags. More...

enum	Defaults { DefaultSymbolSize = 5 }
	Some default values for plots. More...

Public Member Functions
	PlotInstance (const PlotSource::Ptr &source)
	Create a plot instance from the given source. More...

	PlotInstance (const PlotInstance &other)
	Copy constructor.

	~PlotInstance ()
	Destructor.

PlotSource &	source ()
	Access the plot source. More...

const PlotSource &	source () const
	Access the plot source. More...

void	setDefaultProperties ()
	Restore the default style, colour, etc properties.

QString	name () const
	Get the plot name. More...

void	setName (QString name)
	Set the plot name. More...

int	style () const
	Get the draw style: matches `QwtPlotCurve::CurveStyle`. More...

void	setStyle (unsigned style)
	Set the draw style: matches `QwtPlotCurve::CurveStyle`. More...

unsigned	width () const
	Get the draw width. More...

void	setWidth (unsigned width)
	Set the pen draw width: limited to 255. More...

int	symbol () const
	Get the draw symbol: matches `QwtSymbol::Style`. More...

void	setSymbol (int symbol)
	Set the draw symbol: matches `QwtSymbol::Style`. More...

unsigned	symbolSize () const
	Get the symbol size. More...

void	setSymbolSize (unsigned size)
	Set the symbol size: limited to 255. More...

const std::vector< QPointF > &	data () const
	Direct access to the data buffer. More...

const QRgb &	colour () const
	Get the display colour for the plot. More...

void	setColour (const QRgb &colour, bool markExplicit=true)
	Set the display colour, making it explicit unless requested otherwise. More...

const PlotExpression *	expression () const
	Get the expression which generated this plot (`Expression` `source()` only). More...

void	setExpression (const PlotExpression *expression)
	Sets the expression which generated this plot. More...

size_t	ringHead () const
	The read head of the ring buffer. More...

std::uint16_t	flags () const
	Get the status, control and display `Flag` values. More...

bool	testFlags (std::uint16_t flags)
	Sets that all `flags` are set in the `flags()` member. More...

bool	dataComplete () const
	Is data loading complete? More...

void	setComplete ()
	Marks data complete.

bool	isRingBuffer () const
	Is this a ring buffer? More...

void	makeRingBuffer (size_t bufferSize)
	Converts the plot data to a ring buffer of the given size. More...

bool	explicitColour () const
	Using an explicit colour? More...

bool	filterNaN () const
	Filter NaN values on display? More...

void	setFilterNaN (bool filter)
	Set or clear NaN filtering. More...

bool	filterInf () const
	Filter infinite values on display? More...

void	setFilterInf (bool filter)
	Set or clear infinite value filtering. More...

bool	explicitTime () const
	Has the curve been generated with explicit time values? More...

void	setExplicitTime (bool explct)
	Set the state of the `ExplicitTime` `Flag`. More...

QPointF	sample (size_t index) const
	Samples the point at the given index. More...

void	addPoint (const QPointF &p)
	Add a point to the back buffer (thread-safe). More...

void	addPoints (const QPointF *points, size_t pointCount)
	Add multiple points to the back buffer. More...

bool	migrateBuffer ()
	Migrate from the back buffer to `data()`. Main thread only.

PlotInstance &	operator= (const PlotInstance &other)
	Assignment operator. More...

Detailed Description

Holds data for a single curve.

Supports thread-safe, double buffered loading. The data source thread should call addPoint() or addPoints() to add data. Meanwhile the main thread should periodically call migrateBuffer() to move data into the front buffer. Note that only the back buffer is thread-safe. The sample() function should only be called either by the main thread (the same thread doing the migration) or once all data are loaded.

While data can be sampled directly via sample(), a PlotInstanceSampler should be used to resolve time values and time scaling.

Ring Buffer Mode: The structure may be operating in ring buffer mode, in which case the data array is fixed size and added to as a ring buffer. The ringHead marks the start of the ring buffer. The ring buffer is full once the data size equals its capacity.

The PlotInstanceSampler handles sampling in ring buffer mode.

Member Enumeration Documentation

enum PlotInstance::Defaults

Some default values for plots.

Enumerator
DefaultSymbolSize	Default size for displaying plot symbols.

enum PlotInstance::Flag

Status, control and display flags.

Enumerator
DataComplete	Set when all data have been loaded and the curve is complete. No further calls to `migrateBuffer()` required.
RingBuffer	Set if the `data` member acts as a ring buffer. Affects `sample()`, `addPoint()`, `addPoints()`.
ExplicitColour	Set if the graph has been assigned an explicit colour. No colour shift will be performed in plotting the curve.
FilterNaN	Set to filter NaN values, replacing them with zero.
FilterInf	Set to filter infinite values, replacing them zero.
ExplicitTime	Has the curve been generated with explicit time samples? Some generated curves have explicit times and are not subject to time scaling, time shift or time columns. Such curves may need to be renenerated if timing information is changed.

Constructor & Destructor Documentation

PlotInstance::PlotInstance ( const PlotSource::Ptr & source )

Create a plot instance from the given source.

Parameters

source The plot source.

Member Function Documentation

void PlotInstance::addPoint ( const QPointF & p )

Add a point to the back buffer (thread-safe).

Parameters

p	The point to add.

void PlotInstance::addPoints	(	const QPointF *	points,
		size_t	pointCount
	)

Add multiple points to the back buffer.

Parameters

points	The points array to add.
pointCount	The element count of `points`.

const QRgb& PlotInstance::colour ( ) const

inline

Get the display colour for the plot.

May be colour shifted when explicitColour() is false.

Returns: The preferred display colour.

Referenced by setColour().

const std::vector<QPointF>& PlotInstance::data ( ) const

inline

Direct access to the data buffer.

Use sample() for controlled access including ring buffer handling.

Returns: The internal data buffer (visible buffer).

bool PlotInstance::dataComplete ( ) const

inline

Is data loading complete?

Returns: True if all data are present. No further calls to migrateBuffer() required.

References DataComplete.

bool PlotInstance::explicitColour ( ) const

inline

Using an explicit colour?

Returns: True if using an explicit colour.

References ExplicitColour.

bool PlotInstance::explicitTime ( ) const

inline

Has the curve been generated with explicit time values?

Returns: True if generated with explicit time values.

References ExplicitTime.

const PlotExpression* PlotInstance::expression ( ) const

inline

Get the expression which generated this plot (Expression source() only).

Note: this is a shared pointer.

Returns: The generating expression.

Referenced by setExpression().

bool PlotInstance::filterInf ( ) const

inline

Filter infinite values on display?

Returns: True if filtering infinite values.

References FilterInf.

bool PlotInstance::filterNaN ( ) const

inline

Filter NaN values on display?

Returns: True if filtering NaN.

References FilterNaN.

std::uint16_t PlotInstance::flags ( ) const

inline

Get the status, control and display Flag values.

Returns: The set Flag values.

Referenced by testFlags().

bool PlotInstance::isRingBuffer ( ) const

inline

Is this a ring buffer?

Returns: True if using a ring buffer.

References RingBuffer.

void PlotInstance::makeRingBuffer ( size_t bufferSize )

Converts the plot data to a ring buffer of the given size.

This may (safely) resize the existing ring buffer if already a ring buffer.

Parameters

bufferSize The size of the ring buffer.

QString PlotInstance::name ( ) const

inline

Get the plot name.

Returns: The plot name.

Referenced by setName().

PlotInstance& PlotInstance::operator= ( const PlotInstance & other )

Assignment operator.

Copies all members excluding the data back buffer.

Parameters

other The object to copy.

size_t PlotInstance::ringHead ( ) const

inline

The read head of the ring buffer.

Always zero if not isRingBuffer().

Returns: The read head index.

QPointF PlotInstance::sample ( size_t index ) const

Samples the point at the given index.

This caters for ring buffer sampling.

For a non-ring buffer, the index must be in range. For a ring buffer, the index is wrapped into the valid range, except when the buffer is empty.

Parameters

index The sampling index.

void PlotInstance::setColour	(	const QRgb &	colour,
		bool	markExplicit = `true`
	)

inline

Set the display colour, making it explicit unless requested otherwise.

Parameters

colour	The new colour.
markExplicit	True to make `explictColour()` true, preventing colour shift (default).

References colour(), and ExplicitColour.

void PlotInstance::setExplicitTime ( bool explct )

inline

Set the state of the ExplicitTime Flag.

Parameters

explct True to set ExplicitTime, false to clear.

References ExplicitTime.

void PlotInstance::setExpression ( const PlotExpression * expression )

inline

Sets the expression which generated this plot.

Should only be called for Expression source().

Parameters

expression The generating expression.

References expression().

void PlotInstance::setFilterInf ( bool filter )

inline

Set or clear infinite value filtering.

Parameters

filter True to turn on filtering, false to turn off.

References FilterInf.

void PlotInstance::setFilterNaN ( bool filter )

inline

Set or clear NaN filtering.

Parameters

filter True to turn on filtering, false to turn off.

References FilterNaN.

void PlotInstance::setName ( QString name )

inline

Set the plot name.

Parameters

name	The new plot name.

References name().

void PlotInstance::setStyle ( unsigned style )

inline

Set the draw style: matches QwtPlotCurve::CurveStyle.

Parameters

style The new style.

void PlotInstance::setSymbol ( int symbol )

inline

Set the draw symbol: matches QwtSymbol::Style.

Parameters

symbol The new symbol.

void PlotInstance::setSymbolSize ( unsigned size )

inline

Set the symbol size: limited to 255.

Parameters

size	The new symbol size.

void PlotInstance::setWidth ( unsigned width )

inline

Set the pen draw width: limited to 255.

Parameters

width The new width.

PlotSource & PlotInstance::source ( )

inline

Access the plot source.

Returns: The PlotSource owning this plot.

const PlotSource & PlotInstance::source ( ) const

inline

Access the plot source.

Returns: The PlotSource owning this plot.

int PlotInstance::style ( ) const

inline

Get the draw style: matches QwtPlotCurve::CurveStyle.

Returns: The style type.

int PlotInstance::symbol ( ) const

inline

Get the draw symbol: matches QwtSymbol::Style.

Returns: The symbol type.

unsigned PlotInstance::symbolSize ( ) const

inline

Get the symbol size.

Returns: The symbol size.

bool PlotInstance::testFlags ( std::uint16_t flags )

inline

Sets that all flags are set in the flags() member.

Returns: True if all bits an values are set internally.

References flags().

unsigned PlotInstance::width ( ) const

inline

Get the draw width.

Returns: The line width.

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

plotinstance.h

Public Types

Public Member Functions

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation