on linux assume datapath is always relative to cmake_install_prefix, unless you provide an absolute path; on win32/osx hardcode engine path to default installation prefixes (it gets overridden at runtime so it works even if you move the data folder)
#include <QLabel>
#include <QRect>
#include <QList>
#include <QMouseEvent>
class PixLabel : public QLabel
{
Q_OBJECT
public:
PixLabel();
QList<QRect> rects;
public slots:
void AddRect();
private:
void paintEvent(QPaintEvent * event);
void mousePressEvent(QMouseEvent * e);
};