src/GUI/axisitem.cpp

   1 #include <cmath>
   2 #include <QPainter>
   3 #include "common/util.h"
   4 #include "font.h"
   5 #include "axisitem.h"
   6
   7
   8 #define AXIS_WIDTH  1
   9 #define TICK        6
  10 #define PADDING     6
  11 #define XTICKS      15
  12 #define YTICKS      10
  13
  14 class Ticks
  15 {
  16 public:
  17         Ticks(double minValue, double maxValue, int maxCount);
  18
  19         int count() const {return ((int)((_max - _min) / _d)) + 1;}
  20         double val(int i) const {return _min + i * _d;}
  21         double min() const {return _min;}
  22         double max() const {return _max;}
  23
  24 private:
  25         double _min;
  26         double _max;
  27         double _d;
  28 };
  29
  30 Ticks::Ticks(double minValue, double maxValue, int maxCount)
  31 {
  32         double range = Util::niceNum(maxValue - minValue, false);
  33         _d = Util::niceNum(range / maxCount, false);
  34         _min = ceil(minValue / _d) * _d;
  35         _max = floor(maxValue / _d) * _d;
  36 }
  37
  38
  39 AxisItem::AxisItem(Type type, QGraphicsItem *parent)
  40   : QGraphicsItem(parent), _locale(QLocale::system())
  41 {
  42         _type = type;
  43         _size = 0;
  44         _zoom = 1.0;
  45
  46         _font.setPixelSize(FONT_SIZE);
  47         _font.setFamily(FONT_FAMILY);
  48 }
  49
  50 void AxisItem::setRange(const RangeF &range)
  51 {
  52         prepareGeometryChange();
  53         _range = range;
  54
  55         QFontMetrics fm(_font);
  56         Ticks ticks(_range.min(), _range.max(),
  57           (_type == X) ? XTICKS * _zoom : YTICKS * _zoom);
  58         _ticks = QVector<Tick>(ticks.count());
  59
  60         for (int i = 0; i < ticks.count(); i++) {
  61                 Tick &t = _ticks[i];
  62                 t.value = ticks.val(i);
  63                 t.boundingBox = fm.tightBoundingRect(_locale.toString(t.value));
  64         }
  65
  66         updateBoundingRect();
  67         update();
  68 }
  69
  70 void AxisItem::setSize(qreal size)
  71 {
  72         prepareGeometryChange();
  73         _size = size;
  74         updateBoundingRect();
  75         update();
  76 }
  77
  78 void AxisItem::updateBoundingRect()
  79 {
  80         QFontMetrics fm(_font);
  81         QRect es = _ticks.isEmpty() ? QRect() : _ticks.last().boundingBox;
  82         QRect ss = _ticks.isEmpty() ? QRect() : _ticks.first().boundingBox;
  83
  84         if (_type == X) {
  85                 _boundingRect = QRectF(-ss.width()/2, -TICK/2, _size + es.width()/2
  86                   + ss.width()/2, es.height() - 2*fm.descent() + TICK + 2*PADDING);
  87         } else {
  88                 int mtw = 0;
  89                 for (int i = 0; i < _ticks.count(); i++)
  90                         mtw = qMax(_ticks.at(i).boundingBox.width(), mtw);
  91                 _boundingRect = QRectF(-(mtw + 2*PADDING + TICK/2 - fm.descent()),
  92                   -(_size + es.height()/2 + fm.descent()), mtw + 2*PADDING
  93                   + TICK - fm.descent(), _size + es.height()/2 + fm.descent()
  94                   + ss.height()/2);
  95         }
  96 }
  97
  98 void AxisItem::paint(QPainter *painter, const QStyleOptionGraphicsItem *option,
  99           QWidget *widget)
 100 {
 101         Q_UNUSED(option);
 102         Q_UNUSED(widget);
 103         QRect ts;
 104
 105         painter->setRenderHint(QPainter::Antialiasing, false);
 106         painter->setFont(_font);
 107         QPen pen(painter->pen());
 108         pen.setWidth(AXIS_WIDTH);
 109         painter->setPen(pen);
 110
 111         if (_type == X) {
 112                 painter->drawLine(0, 0, _size, 0);
 113
 114                 for (int i = 0; i < _ticks.count(); i++) {
 115                         qreal val = _ticks.at(i).value;
 116                         ts = _ticks.at(i).boundingBox;
 117
 118                         painter->drawLine((_size/_range.size()) * (val - _range.min()),
 119                           TICK/2, (_size/_range.size()) * (val - _range.min()), -TICK/2);
 120                         painter->drawText(((_size/_range.size()) * (val - _range.min()))
 121                           - (ts.width()/2), ts.height() + TICK/2 + PADDING,
 122                           _locale.toString(val));
 123                 }
 124         } else {
 125                 painter->drawLine(0, 0, 0, -_size);
 126
 127                 int mtw = 0;
 128                 for (int i = 0; i < _ticks.count(); i++) {
 129                         qreal val = _ticks.at(i).value;
 130                         ts = _ticks.at(i).boundingBox;
 131                         mtw = qMax(ts.width(), mtw);
 132
 133                         painter->drawLine(TICK/2, -((_size/_range.size())
 134                           * (val - _range.min())), -TICK/2, -((_size/_range.size())
 135                           * (val - _range.min())));
 136                         painter->drawText(-(ts.width() + PADDING + TICK/2),
 137                           -((_size/_range.size()) * (val - _range.min())) + (ts.height()/2),
 138                           _locale.toString(val));
 139                 }
 140         }
 141
 142         //painter->setPen(Qt::red);
 143         //painter->drawRect(boundingRect());
 144 }
 145
 146 QSizeF AxisItem::margin() const
 147 {
 148         QFontMetrics fm(_font);
 149         QRect es = _ticks.isEmpty() ? QRect() : _ticks.last().boundingBox;
 150
 151         if (_type == X) {
 152                 return QSizeF(es.width()/2, es.height() - 2*fm.descent() + TICK/2
 153                   + 2*PADDING);
 154         } else {
 155                 int mtw = 0;
 156                 for (int i = 0; i < _ticks.count(); i++)
 157                         mtw = qMax(_ticks.at(i).boundingBox.width(), mtw);
 158
 159                 return QSizeF(mtw + 2*PADDING + TICK/2 - fm.descent(),
 160                   es.height()/2 + fm.descent());
 161         }
 162 }
 163
 164 QList<qreal> AxisItem::ticks() const
 165 {
 166         QList<qreal> list;
 167
 168         for (int i = 0; i < _ticks.count(); i++)
 169                 list.append(((_size/_range.size()) * (_ticks.at(i).value
 170                   - _range.min())));
 171
 172         return list;
 173 }