Add MapRuler (right-click & drag in events view)

include/ui/mapruler.h

@@ -0,0 +1,71 @@
+#ifndef MAPRULER_H
+#define MAPRULER_H
+
+#include <QGraphicsItem>
+#include <QPainter>
+#include <QColor>
+
+
+class MapRuler : public QGraphicsItem, private QLine
+{
+public:
+    MapRuler(QColor interior = Qt::yellow, QColor exterior = Qt::black)
+    : interiorColor(interior), exteriorColor(exterior)
+    {
+        init();
+        setAcceptedMouseButtons(Qt::RightButton);
+    }
+    void init();
+    QRectF boundingRect() const override;
+    void paint(QPainter *painter, const QStyleOptionGraphicsItem *, QWidget *) override;
+    QPainterPath shape() const override;
+
+    // Anchor the ruler on metatile 'tilePos' and show the ruler
+    void setAnchor(const QPoint &tilePos);
+    // Anchor the ruler on metatile (tileX,tileY) and show the ruler
+    void setAnchor(int tileX, int tileY) { setAnchor(QPoint(tileX, tileY)); }
+    // Release the ruler anchor and hide the ruler
+    void endAnchor();
+    // Set the ruler end point to metatile 'tilePos' and repaint
+    void setEndPos(const QPoint &tilePos);
+    // Set the ruler end point to metatile (tileX, tileY) and repaint
+    void setEndPos(int tileX, int tileY) { setEndPos(QPoint(tileX, tileY)); }
+    
+    // Ruler start point in metatiles
+    QPoint anchor() const { return QLine::p1(); }
+    // Ruler end point in metatiles
+    QPoint endPos() const { return QLine::p2(); }
+    // X-coordinate of the ruler left edge in metatiles
+    int left() const { return qMin(anchor().x(), endPos().x()); }
+    // Y-coordinate of the ruler top edge in metatiles
+    int top() const { return qMin(anchor().y(), endPos().y()); }
+    // Horizontal component of the ruler in metatiles
+    int deltaX() const { return QLine::dx(); }
+    // Vertical component of the ruler in metatiles
+    int deltaY() const { return QLine::dy(); }
+    // Ruler width in metatiles
+    int width() const { return qAbs(deltaX()); }
+    // Ruler height in metatiles
+    int height() const { return qAbs(deltaY()); }
+    // Ruler width in map pixels
+    int pixWidth() const { return width() * 16; } 
+    // Ruler height in map pixels
+    int pixHeight() const { return height() * 16; }
+
+    bool mousePressed(Qt::MouseButtons buttons) { return buttons & acceptedMouseButtons(); }
+
+private:
+    QRect xRuler;
+    QRect yRuler;
+    QRect widthTextBox;
+    QRect heightTextBox;
+    QColor interiorColor;
+    QColor exteriorColor;
+
+    static int padding;
+    static int thickness;
+    
+    void updateShape();
+};
+
+#endif // MAPRULER_H