ground/gcs/src/libs/qwt/src/qwt_plot_rescaler.h

   1 /* -*- mode: C++ ; c-file-style: "stroustrup" -*- *****************************
   2  * Qwt Widget Library
   3  * Copyright (C) 1997   Josef Wilgen
   4  * Copyright (C) 2002   Uwe Rathmann
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the Qwt License, Version 1.0
   8  *****************************************************************************/
   9
  10 #ifndef QWT_PLOT_RESCALER_H
  11 #define QWT_PLOT_RESCALER_H 1
  12
  13 #include "qwt_global.h"
  14 #include "qwt_interval.h"
  15 #include "qwt_plot.h"
  16 #include <qobject.h>
  17
  18 class QwtPlot;
  19 class QResizeEvent;
  20
  21 /*!
  22     \brief QwtPlotRescaler takes care of fixed aspect ratios for plot scales
  23
  24     QwtPlotRescaler auto adjusts the axes of a QwtPlot according
  25     to fixed aspect ratios.
  26 */
  27
  28 class QWT_EXPORT QwtPlotRescaler: public QObject
  29 {
  30 public:
  31     /*!
  32       The rescale policy defines how to rescale the reference axis and
  33       their depending axes.
  34
  35       \sa ExpandingDirection, setIntervalHint()
  36     */
  37     enum RescalePolicy
  38     {
  39         /*!
  40           The interval of the reference axis remains unchanged, when the
  41           geometry of the canvas changes. All other axes
  42           will be adjusted according to their aspect ratio.
  43          */
  44         Fixed,
  45
  46         /*!
  47           The interval of the reference axis will be shrunk/expanded,
  48           when the geometry of the canvas changes. All other axes
  49           will be adjusted according to their aspect ratio.
  50
  51           The interval, that is represented by one pixel is fixed.
  52
  53          */
  54         Expanding,
  55
  56         /*!
  57           The intervals of the axes are calculated, so that all axes include
  58           their interval hint.
  59          */
  60         Fitting
  61     };
  62
  63     /*!
  64        When rescalePolicy() is set to Expanding its direction depends
  65        on ExpandingDirection
  66      */
  67     enum ExpandingDirection
  68     {
  69         //! The upper limit of the scale is adjusted
  70         ExpandUp,
  71
  72         //! The lower limit of the scale is adjusted
  73         ExpandDown,
  74
  75         //! Both limits of the scale are adjusted
  76         ExpandBoth
  77     };
  78
  79     explicit QwtPlotRescaler( QWidget *canvas,
  80         int referenceAxis = QwtPlot::xBottom,
  81         RescalePolicy = Expanding );
  82
  83     virtual ~QwtPlotRescaler();
  84
  85     void setEnabled( bool );
  86     bool isEnabled() const;
  87
  88     void setRescalePolicy( RescalePolicy );
  89     RescalePolicy rescalePolicy() const;
  90
  91     void setExpandingDirection( ExpandingDirection );
  92     void setExpandingDirection( int axis, ExpandingDirection );
  93     ExpandingDirection expandingDirection( int axis ) const;
  94
  95     void setReferenceAxis( int axis );
  96     int referenceAxis() const;
  97
  98     void setAspectRatio( double ratio );
  99     void setAspectRatio( int axis, double ratio );
 100     double aspectRatio( int axis ) const;
 101
 102     void setIntervalHint( int axis, const QwtInterval& );
 103     QwtInterval intervalHint( int axis ) const;
 104
 105     QWidget *canvas();
 106     const QWidget *canvas() const;
 107
 108     QwtPlot *plot();
 109     const QwtPlot *plot() const;
 110
 111     virtual bool eventFilter( QObject *, QEvent * );
 112
 113     void rescale() const;
 114
 115 protected:
 116     virtual void canvasResizeEvent( QResizeEvent * );
 117
 118     virtual void rescale( const QSize &oldSize, const QSize &newSize ) const;
 119     virtual QwtInterval expandScale(
 120         int axis, const QSize &oldSize, const QSize &newSize ) const;
 121
 122     virtual QwtInterval syncScale(
 123         int axis, const QwtInterval& reference,
 124         const QSize &size ) const;
 125
 126     virtual void updateScales(
 127         QwtInterval intervals[QwtPlot::axisCnt] ) const;
 128
 129     Qt::Orientation orientation( int axis ) const;
 130     QwtInterval interval( int axis ) const;
 131     QwtInterval expandInterval( const QwtInterval &,
 132         double width, ExpandingDirection ) const;
 133
 134 private:
 135     double pixelDist( int axis, const QSize & ) const;
 136
 137     class AxisData;
 138     class PrivateData;
 139     PrivateData *d_data;
 140 };
 141
 142 #endif