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/* -*- 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
*****************************************************************************/
#include "qwt_painter.h"
#include "qwt_scale_div.h"
#include "qwt_scale_map.h"
#include "qwt_math.h"
#include <qpen.h>
#include <qpainter.h>
#include <qfontmetrics.h>
#include <qmath.h>
class QwtRoundScaleDraw::PrivateData
{
public:
PrivateData():
center( 50.0, 50.0 ),
radius( 50.0 ),
startAngle( -135.0 ),
endAngle( 135.0 )
{
};
/*!
\brief Constructor
The range of the scale is initialized to [0, 100],
The center is set to (50, 50) with a radius of 50.
The angle range is set to [-135, 135].
*/
QwtRoundScaleDraw::QwtRoundScaleDraw()
{
d_data = new QwtRoundScaleDraw::PrivateData;
setRadius( 50 );
scaleMap().setPaintInterval( d_data->startAngle, d_data->endAngle );
}
//! Destructor
QwtRoundScaleDraw::~QwtRoundScaleDraw()
{
delete d_data;
}
/*!
Change of radius the scale
Radius is the radius of the backbone without ticks and labels.
\param radius New Radius
Radius is the radius of the backbone without ticks and labels.
{
return d_data->radius;
}
/*!
Move the center of the scale draw, leaving the radius unchanged
\param center New center
{
d_data->center = center;
}
//! Get the center of the scale
{
return d_data->center;
}
/*!
\brief Adjust the baseline circle segment for round scales.
The baseline will be drawn from min(angle1,angle2) to max(angle1, angle2).
The default setting is [ -135, 135 ].
An angle of 0 degrees corresponds to the 12 o'clock position,
and positive angles count in a clockwise direction.
\param angle1
\param angle2 boundaries of the angle interval in degrees.
<li>The angle range is limited to [-360, 360] degrees. Angles exceeding
this range will be clipped.
<li>For angles more or equal than 360 degrees above or below min(angle1, angle2),
<li>If you need a counterclockwise scale, use QwtScaleDiv::setInterval()
void QwtRoundScaleDraw::setAngleRange( double angle1, double angle2 )
#if 0
angle1 = qBound( -360.0, angle1, 360.0 );
angle2 = qBound( -360.0, angle2, 360.0 );
#endif
scaleMap().setPaintInterval( d_data->startAngle, d_data->endAngle );
}
/*!
Draws the label for a major scale tick
\param painter Painter
\param value Value
\sa drawTick(), drawBackbone()
*/
void QwtRoundScaleDraw::drawLabel( QPainter *painter, double value ) const
const double tval = scaleMap().transform( value );
if ( ( tval >= d_data->startAngle + 360.0 )
|| ( tval <= d_data->startAngle - 360.0 ) )
{
if ( hasComponent( QwtAbstractScaleDraw::Ticks ) ||
hasComponent( QwtAbstractScaleDraw::Backbone ) )
{
if ( hasComponent( QwtAbstractScaleDraw::Ticks ) )
radius += tickLength( QwtScaleDiv::MajorTick );
const QSizeF sz = label.textSize( painter->font() );
const double arc = qwtRadians( tval );
const double x = d_data->center.x() +
( radius + sz.width() / 2.0 ) * qSin( arc );
const double y = d_data->center.y() -
( radius + sz.height() / 2.0 ) * qCos( arc );
const QRectF r( x - sz.width() / 2, y - sz.height() / 2,
sz.width(), sz.height() );
label.draw( painter, r );
\param painter Painter
\param value Value of the tick
\param len Lenght of the tick
void QwtRoundScaleDraw::drawTick( QPainter *painter, double value, double len ) const
const double cx = d_data->center.x();
const double cy = d_data->center.y();
const double radius = d_data->radius;
if ( ( tval < d_data->startAngle + 360.0 )
|| ( tval > d_data->startAngle - 360.0 ) )
{
const double arc = qwtRadians( tval );
const double sinArc = qSin( arc );
const double cosArc = qCos( arc );
const double x1 = cx + radius * sinArc;
const double x2 = cx + ( radius + len ) * sinArc;
const double y1 = cy - radius * cosArc;
const double y2 = cy - ( radius + len ) * cosArc;
}
}
/*!
Draws the baseline of the scale
\param painter Painter
\sa drawTick(), drawLabel()
*/
void QwtRoundScaleDraw::drawBackbone( QPainter *painter ) const
const double deg1 = scaleMap().p1();
const double deg2 = scaleMap().p2();
const int a1 = qRound( qMin( deg1, deg2 ) - 90 );
const int a2 = qRound( qMax( deg1, deg2 ) - 90 );
const double radius = d_data->radius;
const double x = d_data->center.x() - radius;
const double y = d_data->center.y() - radius;
painter->drawArc( QRectF( x, y, 2 * radius, 2 * radius ),
-a2 * 16, ( a2 - a1 + 1 ) * 16 ); // counterclockwise
The extent is the distance between the baseline to the outermost
pixel of the scale draw. radius() + extent() is an upper limit
for the radius of the bounding circle.
\param font Font used for painting the labels
calculates only an upper limit, that might be a
few pixels too large
*/
const QList<double> &ticks = sd.ticks( QwtScaleDiv::MajorTick );
for ( int i = 0; i < ticks.count(); i++ )
{
const double tval = scaleMap().transform( value );
if ( ( tval < d_data->startAngle + 360 )
&& ( tval > d_data->startAngle - 360 ) )
{
const double arc = qwtRadians( tval );
const QSizeF sz = label.textSize( font );
const double off = qMax( sz.width(), sz.height() );
double x = off * qSin( arc );
double y = off * qCos( arc );
if ( hasComponent( QwtAbstractScaleDraw::Ticks ) )
{
d += maxTickLength();
if ( hasComponent( QwtAbstractScaleDraw::Backbone ) )
{
const double pw = qMax( 1, penWidth() ); // pen width can be zero
if ( hasComponent( QwtAbstractScaleDraw::Labels ) &&
( hasComponent( QwtAbstractScaleDraw::Ticks ) ||
hasComponent( QwtAbstractScaleDraw::Backbone ) ) )
{