gistfile1.m

- (void)visit {
    float x = 0;
    float y = 150;
    float width = 320;
    float height = 180;

    glEnable(GL_SCISSOR_TEST);
    if([[CCDirector sharedDirector] enableRetinaDisplay:YES]) {
        glScissor(2 * x, 2 * y, 2 * width, 2 * height);
    } else {
        glScissor(x, y, width, height);
    }
    [super visit];
    glDisable(GL_SCISSOR_TEST);
    
}