левое нижнее glViewport width height glMatrixMode GL_PROJECTION glLoad

//левое нижнее
glViewport(0,0,width/2,height/2);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    glOrtho(-SCREEN_WIDTH/2, SCREEN_WIDTH/2, -SCREEN_HEIGHT/2, SCREEN_HEIGHT/2, 0, 1000);
    
    glTranslatef(0,0,-500);
    glRotatef(270, 0, 1, 0);
    glTranslatef(-0,-0,500);
    
    
     //левое верхнее
    glViewport(0,height/2,width/2,height/2);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    glOrtho(-SCREEN_WIDTH/2, SCREEN_WIDTH/2, -SCREEN_HEIGHT/2, SCREEN_HEIGHT/2, 0, 1000);

    //правое верхнее
    glViewport(width/2,height/2,width/2,height/2);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    glOrtho(-SCREEN_WIDTH/2, SCREEN_WIDTH/2, -SCREEN_HEIGHT/2, SCREEN_HEIGHT/2, 0, 1000);