Here we are, the Mandelbrot algorithm is done and the multi-threading system is ready to compute complex fractals over all your CPU cores. We can now create the widget that will convert all JobResult to display a pretty picture. Create a new C++ class called MandelbrotWidget. For this widget, we will handle the painting ourselves. Thus, we do not need any .uiQt Designer Form file. Let's begin with the MandelbrotWidget.h file:

#include <memory> 
 
#include <QWidget> 
#include <QPoint> 
#include <QThread> 
#include <QList> 
 
#include "MandelbrotCalculator.h" 
 
class QResizeEvent; 
 
class MandelbrotWidget : public QWidget 
{ 
    Q_OBJECT 
 
public: 
    explicit MandelbrotWidget(QWidget *parent = 0); 
    ~MandelbrotWidget(); 
 
private: 
    MandelbrotCalculator mMandelbrotCalculator; 
    QThread mThreadCalculator; 
    double mScaleFactor; 
    QPoint mLastMouseMovePosition; 
    QPointF mMoveOffset; 
    QSize...