displayData.cpp

displayData::displayData(QPainter *painter)
{
    painter->setFont(QFont("times", 13));
    painter->drawText(5,15, QString("Speed: " + QString::number(speed)));
    painter->drawText(5, 30, QString("Rotation: " + QString::number(planeRotation)));
}

		displayData.h

#ifndef DISPLAYDATA
#define DISPLAYDATA

#include <QGraphicsTextItem>

class displayData : public QGraphicsTextItem{
public:
    displayData(QPainter *painter);
private:
};

#endif // DISPLAYDATA


		game.cpp (relevant lines)

data = new displayData();
    scene->addItem(data);