Try to be friendlier to small screen sizes. Use 800x600 if width/height of 2/3rds is smaller than 800x600 (things don't look smaller than that size), use desktop size if it is for some reason smaller than 800x600
#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);
};