qwt_point_data.cpp

/******************************************************************************
 * 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
 *****************************************************************************/
 
#include "qwt_point_data.h"
 
QwtSyntheticPointData::QwtSyntheticPointData(
        size_t size, const QwtInterval& interval )
    : m_size( size )
    , m_interval( interval )
{
}
 
void QwtSyntheticPointData::setSize( size_t size )
{
    m_size = size;
}
 
size_t QwtSyntheticPointData::size() const
{
    return m_size;
}
 
void QwtSyntheticPointData::setInterval( const QwtInterval& interval )
{
    m_interval = interval.normalized();
}
 
QwtInterval QwtSyntheticPointData::interval() const
{
    return m_interval;
}
 
void QwtSyntheticPointData::setRectOfInterest( const QRectF& rect )
{
    m_rectOfInterest = rect;
    m_intervalOfInterest = QwtInterval(
        rect.left(), rect.right() ).normalized();
}
 
QRectF QwtSyntheticPointData::rectOfInterest() const
{
    return m_rectOfInterest;
}
 
QRectF QwtSyntheticPointData::boundingRect() const
{
    if ( m_size == 0 ||
        !( m_interval.isValid() || m_intervalOfInterest.isValid() ) )
    {
        return QRectF( 1.0, 1.0, -2.0, -2.0 ); // something invalid
    }
 
    return qwtBoundingRect( *this );
}
 
QPointF QwtSyntheticPointData::sample( size_t index ) const
{
    if ( index >= m_size )
        return QPointF( 0, 0 );
 
    const double xValue = x( index );
    const double yValue = y( xValue );
 
    return QPointF( xValue, yValue );
}
 
double QwtSyntheticPointData::x( uint index ) const
{
    const QwtInterval& interval = m_interval.isValid() ?
        m_interval : m_intervalOfInterest;
 
    if ( !interval.isValid() )
        return 0.0;
 
    if ( m_size <= 1 )
        return interval.minValue();
 
    const double dx = interval.width() / ( m_size - 1 );
    return interval.minValue() + index * dx;
}