xdsopl-qsstv/qwt/qwt_point_polar.cpp

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3.1 KiB
C++

/* -*- mode: C++ ; c-file-style: "stroustrup" -*- *****************************
* QwtPolar Widget Library
* Copyright (C) 2008 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_polar.h"
#include "qwt_math.h"
#if QT_VERSION < 0x040601
#define qAtan2(y, x) ::atan2(y, x)
#endif
/*!
Convert and assign values from a point in Cartesian coordinates
\param p Point in Cartesian coordinates
\sa setPoint(), toPoint()
*/
QwtPointPolar::QwtPointPolar( const QPointF &p )
{
d_radius = qSqrt( qwtSqr( p.x() ) + qwtSqr( p.y() ) );
d_azimuth = qAtan2( p.y(), p.x() );
}
/*!
Convert and assign values from a point in Cartesian coordinates
\param p Point in Cartesian coordinates
*/
void QwtPointPolar::setPoint( const QPointF &p )
{
d_radius = qSqrt( qwtSqr( p.x() ) + qwtSqr( p.y() ) );
d_azimuth = qAtan2( p.y(), p.x() );
}
/*!
Convert and return values in Cartesian coordinates
\return Converted point in Cartesian coordinates
\note Invalid or null points will be returned as QPointF(0.0, 0.0)
\sa isValid(), isNull()
*/
QPointF QwtPointPolar::toPoint() const
{
if ( d_radius <= 0.0 )
return QPointF( 0.0, 0.0 );
const double x = d_radius * qCos( d_azimuth );
const double y = d_radius * qSin( d_azimuth );
return QPointF( x, y );
}
/*!
\brief Compare 2 points
Two points are equal to each other if radius and
azimuth-coordinates are the same. Points are not equal, when
the azimuth differs, but other.azimuth() == azimuth() % (2 * PI).
\return True if the point is equal to other; otherwise return false.
\sa normalized()
*/
bool QwtPointPolar::operator==( const QwtPointPolar &other ) const
{
return d_radius == other.d_radius && d_azimuth == other.d_azimuth;
}
/*!
Compare 2 points
Two points are equal to each other if radius and
azimuth-coordinates are the same. Points are not equal, when
the azimuth differs, but other.azimuth() == azimuth() % (2 * PI).
\return True if the point is not equal to other; otherwise return false.
\sa normalized()
*/
bool QwtPointPolar::operator!=( const QwtPointPolar &other ) const
{
return d_radius != other.d_radius || d_azimuth != other.d_azimuth;
}
/*!
Normalize radius and azimuth
When the radius is < 0.0 it is set to 0.0. The azimuth is
a value >= 0.0 and < 2 * M_PI.
\return Normalized point
*/
QwtPointPolar QwtPointPolar::normalized() const
{
const double radius = qMax( d_radius, 0.0 );
double azimuth = d_azimuth;
if ( azimuth < -2.0 * M_PI || azimuth >= 2 * M_PI )
azimuth = ::fmod( d_azimuth, 2 * M_PI );
if ( azimuth < 0.0 )
azimuth += 2 * M_PI;
return QwtPointPolar( azimuth, radius );
}
#ifndef QT_NO_DEBUG_STREAM
QDebug operator<<( QDebug debug, const QwtPointPolar &point )
{
debug.nospace() << "QwtPointPolar("
<< point.azimuth() << "," << point.radius() << ")";
return debug.space();
}
#endif