// NOTE: To run, it is recommended not to be in Compiz or Beryl, they have shown some instability.
 
#include "wx/wx.h"
#include "wx/glcanvas.h"
 
#ifdef __WXMAC__
#include "GLUT/glut.h"
#else
#include "GL/glut.h"
#endif
 
#ifndef WIN32
#include <unistd.h> // FIXME: ¿This work/necessary in Windows?
                    //Not necessary, but if it was, it needs to be replaced by process.h AND io.h
#endif
 
class wxGLCanvasSubClass: public wxGLCanvas {
        void Render();
public:
    wxGLCanvasSubClass(wxFrame* parent);
    void Paintit(wxPaintEvent& event);
protected:
    DECLARE_EVENT_TABLE()
};
 
BEGIN_EVENT_TABLE(wxGLCanvasSubClass, wxGLCanvas)
    EVT_PAINT    (wxGLCanvasSubClass::Paintit)
END_EVENT_TABLE()
 
wxGLCanvasSubClass::wxGLCanvasSubClass(wxFrame *parent)
:wxGLCanvas(parent, wxID_ANY,  wxDefaultPosition, wxDefaultSize, 0, wxT("GLCanvas")){
    int argc = 1;
    char* argv[1] = { wxString((wxTheApp->argv)[0]).char_str() };
 
/*
NOTE: this example uses GLUT in order to have a free teapot model
to display, to show 3D capabilities. GLUT, however, seems to cause problems
on some systems. If you meet problems, first try commenting out glutInit(),
then try comeenting out all glut code
*/
    glutInit(&argc, argv);
}
 
 
void wxGLCanvasSubClass::Paintit(wxPaintEvent& WXUNUSED(event)){
    Render();
}
 
void wxGLCanvasSubClass::Render()
{
    SetCurrent();
    wxPaintDC(this);
    glClearColor(0.0, 0.0, 0.0, 0.0);
    glClear(GL_COLOR_BUFFER_BIT);
    glViewport(0, 0, (GLint)GetSize().x, (GLint)GetSize().y);
 
    glBegin(GL_POLYGON);
        glColor3f(1.0, 1.0, 1.0);
        glVertex2f(-0.5, -0.5);
        glVertex2f(-0.5, 0.5);
        glVertex2f(0.5, 0.5);
        glVertex2f(0.5, -0.5);
        glColor3f(0.4, 0.5, 0.4);
        glVertex2f(0.0, -0.8);
    glEnd();
 
    glBegin(GL_POLYGON);
        glColor3f(1.0, 0.0, 0.0);
        glVertex2f(0.1, 0.1);
        glVertex2f(-0.1, 0.1);
        glVertex2f(-0.1, -0.1);
        glVertex2f(0.1, -0.1);
    glEnd();
 
// using a little of glut
    glColor4f(0,0,1,1);
    glutWireTeapot(0.4);
 
    glLoadIdentity();
    glColor4f(2,0,1,1);
    glutWireTeapot(0.6);
// done using glut
 
    glFlush();
    SwapBuffers();
}
 
class MyApp: public wxApp
{
    virtual bool OnInit();
    wxGLCanvas * MyGLCanvas;
};
 
 
IMPLEMENT_APP(MyApp)
 
  
bool MyApp::OnInit()
{
    wxFrame *frame = new wxFrame((wxFrame *)NULL, -1,  wxT("Hello GL World"), wxPoint(50,50), wxSize(200,200));
    new wxGLCanvasSubClass(frame);
 
    frame->Show(TRUE);
    return TRUE;
}