Other code

#include "wx/wx.h"
#include "wx/dcbuffer.h"
#include "vector"
using namespace std;


class MyFrame : public wxFrame {
public:
wxPen blackPen3;
wxColor brown;
wxColor yellow;
wxColor blue;
wxBrush brownBrush;
wxBrush yellowBrush;
wxBrush blueBrush;
wxBrush *wxBROWN_BRUSH;
vector<wxPoint> mountainPeaks;
MyFrame (const wxString& title) : wxFrame(nullptr, wxID_ANY, title, wxPoint(50,50), wxSize(640,500)){
SetBackgroundStyle (wxBG_STYLE_PAINT);
blackPen3 = wxPen(*wxBLACK);
blackPen3.SetWidth (3);
brown = wxColor (165,42,42);
yellow = wxColor (255,255,0);
blue = wxColor (0,0,255);
brownBrush= wxBrush(brown);
yellowBrush= wxBrush(yellow);
blueBrush= wxBrush(blue);
*wxBROWN_BRUSH= wxBrush(brown);
mountainPeaks = vector<wxPoint> {wxPoint(640,0), wxPoint(540,40),wxPoint(600,55),wxPoint(520,85),wxPoint(600,100),wxPoint(560,120),wxPoint(640,150)};
Bind(wxEVT_PAINT, &MyFrame :: OnPaint,this);
Bind(wxEVT_CLOSE_WINDOW, &MyFrame ::OnClose, this);
}



void OnClose (wxCloseEvent& event){
        Destroy();
    }
void OnPaint(wxPaintEvent &event){
wxAutoBufferedPaintDC dc(this);
dc.SetBackground(blueBrush);
dc.Clear();
dc.SetPen(blackPen3);
dc.SetBrush(*wxYELLOW_BRUSH);
dc.DrawEllipse(wxPoint(0,500), wxSize(70,70));
dc.SetBrush(*wxBROWN_BRUSH);
dc.DrawPolygon(mountainPeaks.size(), mountainPeaks.data());
}
};

class MyApp : public wxApp{
public:
    virtual bool OnInit(){
        MyFrame *frame = new MyFrame (wxT("mountains"));
        frame->Show(true);
        return true;
    }
};
IMPLEMENT_APP(MyApp)