QwtPixelMatrix Class Reference

A bit field corresponding to the pixels of a rectangle. More...

#include <qwt_pixel_matrix.h>

Inheritance diagram for QwtPixelMatrix:

Public Member Functions
	QwtPixelMatrix (const QRect &rect)
	Constructor. More...
	~QwtPixelMatrix ()
	Destructor.
void	setRect (const QRect &rect)
QRect	rect () const
bool	testPixel (int x, int y) const
	Test if a pixel has been set. More...
bool	testAndSetPixel (int x, int y, bool on)
	Set a pixel and test if a pixel has been set before. More...
int	index (int x, int y) const
	Calculate the index in the bit field corresponding to a position. More...

Detailed Description

A bit field corresponding to the pixels of a rectangle.

QwtPixelMatrix is intended to filter out duplicates in an unsorted array of points.

Constructor & Destructor Documentation

QwtPixelMatrix()

QwtPixelMatrix::QwtPixelMatrix

(

const QRect &

rect

)

Constructor.

Parameters

rect	Bounding rectangle for the matrix

Member Function Documentation

index()

int QwtPixelMatrix::index ( int  x, int  y  ) const

inline

Calculate the index in the bit field corresponding to a position.

Parameters

x	X-coordinate
y	Y-coordinate

Returns

Index, when rect() contains pos - otherwise -1.

rect()

QRect QwtPixelMatrix::rect

(

)

const

Returns

Bounding rectangle

setRect()

void QwtPixelMatrix::setRect

(

const QRect &

rect

)

Set the bounding rectangle of the matrix

Parameters

rect	Bounding rectangle

Note

All bits are cleared

testAndSetPixel()

bool QwtPixelMatrix::testAndSetPixel ( int  x, int  y, bool  on  )

inline

Set a pixel and test if a pixel has been set before.

Parameters

x	X-coordinate
y	Y-coordinate
on	Set/Clear the pixel

Returns

true, when pos is outside of rect(), or when the pixel was set before.

testPixel()

bool QwtPixelMatrix::testPixel ( int  x, int  y  ) const

inline

Test if a pixel has been set.

Parameters

x	X-coordinate
y	Y-coordinate

Returns

true, when pos is outside of rect(), or when the pixel has already been set.