void glProjection() and void initRender()

void glProjection()
{
    glLoadIdentity();
    glMatrixMode(GL_PROJECTION);
    gluPerspective(70, (GLdouble)windowWidth / (GLdouble)windowHeight, 0.1, zfar);
    glViewport(0, 0, windowWidth, windowHeight);
}

void initRender()
{
    // SECRET

    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluOrtho2D(0, windowWidth, 0, windowHeight);

    glDisable(GL_DEPTH_TEST);
    glEnable(GL_TEXTURE_2D);
    glClear(GL_COLOR_BUFFER_BIT);

    initializeGui();
    renderThread = thread(&renderEvent);

    // SECRET

}