qwt_pixel_matrix.h
/* -*- mode: C++ ; c-file-style: "stroustrup" -*- *****************************
* Qwt Widget Library
* Copyright (C) 1997 Josef Wilgen
* Copyright (C) 2002 Uwe Rathmann
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the Qwt License, Version 1.0
*****************************************************************************/
#ifndef QWT_PIXEL_MATRIX_H
#define QWT_PIXEL_MATRIX_H
#include "qwt_global.h"
#include <qbitarray.h>
#include <qrect.h>
class QWT_EXPORT QwtPixelMatrix: public QBitArray
{
public:
QwtPixelMatrix( const QRect& rect );
~QwtPixelMatrix();
void setRect( const QRect& rect );
QRect rect() const;
bool testPixel( int x, int y ) const;
bool testAndSetPixel( int x, int y, bool on );
int index( int x, int y ) const;
private:
QRect d_rect;
};
inline bool QwtPixelMatrix::testPixel( int x, int y ) const
{
const int idx = index( x, y );
return ( idx >= 0 ) ? testBit( idx ) : true;
}
inline bool QwtPixelMatrix::testAndSetPixel( int x, int y, bool on )
{
const int idx = index( x, y );
if ( idx < 0 )
return true;
const bool onBefore = testBit( idx );
setBit( idx, on );
return onBefore;
}
inline int QwtPixelMatrix::index( int x, int y ) const
{
const int dx = x - d_rect.x();
if ( dx < 0 || dx >= d_rect.width() )
return -1;
const int dy = y - d_rect.y();
if ( dy < 0 || dy >= d_rect.height() )
return -1;
return dy * d_rect.width() + dx;
}
#endif
QwtPixelMatrix::testPixel
bool testPixel(int x, int y) const
Test if a pixel has been set.
Definition: qwt_pixel_matrix.h:50
QwtPixelMatrix::testAndSetPixel
bool testAndSetPixel(int x, int y, bool on)
Set a pixel and test if a pixel has been set before.
Definition: qwt_pixel_matrix.h:66
QwtPixelMatrix
A bit field corresponding to the pixels of a rectangle.
Definition: qwt_pixel_matrix.h:23
QwtPixelMatrix::index
int index(int x, int y) const
Calculate the index in the bit field corresponding to a position.
Definition: qwt_pixel_matrix.h:85