QwtSeriesData< T > Class Template Reference

#include <qwt_series_data.h>

Inheritance diagram for QwtSeriesData< T >:

Inheritance graph
[legend]

List of all members.

Public Member Functions

virtual QwtSeriesDatacopy () const =0
virtual size_t size () const =0
virtual T sample (size_t i) const =0
virtual QwtDoubleRect boundingRect () const =0
virtual void setRectOfInterest (const QwtDoubleRect &)


Detailed Description

template<typename T>
class QwtSeriesData< T >

Abstract interface for iterating over samples

Qwt offers several implementations of the QwtSeriesData API, but in situations, where data of an application specific format needs to be displayed, without having to copy it, it is recommended to implement an individual data access.


Member Function Documentation

template<typename T>
virtual QwtDoubleRect QwtSeriesData< T >::boundingRect (  )  const [pure virtual]

Calculate the bounding rect of all samples

The bounding rect is necessary for autoscaling and can be used for a couple of painting optimizations.

qwtBoundingRect(...) offers slow implementations iterating over the samples. For large sets it is recommended to implement something faster f.e. by caching the bounding rect.

Implemented in QwtPointSeriesData, QwtIntervalSeriesData, QwtSetSeriesData, QwtPointArrayData, QwtCPointerData, and QwtSyntheticPointData.

template<typename T>
virtual QwtSeriesData* QwtSeriesData< T >::copy (  )  const [pure virtual]

Virtual copy constructor

When accessing a large amount of samples it is recommended to copy only the interface (shallow copy) to them.

Returns:
Pointer to a copy

Implemented in QwtPointSeriesData, QwtIntervalSeriesData, QwtSetSeriesData, QwtPointArrayData, and QwtCPointerData.

template<typename T>
virtual T QwtSeriesData< T >::sample ( size_t  i  )  const [pure virtual]

template<typename T>
virtual void QwtSeriesData< T >::setRectOfInterest ( const QwtDoubleRect &   )  [inline, virtual]

Set a the "rect of interest"

QwtPlotSeriesItem defines the current area of the plot canvas as "rect of interest" ( QwtPlotSeriesItem::updateScaleDiv() ). It can be used to implement different levels of details.

The default implementation does nothing.

Reimplemented in QwtSyntheticPointData.

template<typename T>
virtual size_t QwtSeriesData< T >::size (  )  const [pure virtual]


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