def setToRed(surface):
    """Inverts the colors of a pygame Screen"""
    surface.lock()
    for x in range(surface.get_width()):
        for y in range(surface.get_height()):
            r, g, b, a = surface.get_at((x, y))
            greyscale = r * 0.298 + g * 0.587 + b * 0.114
            surface.set_at((x, y), (greyscale, 0, 0, a))
    surface.unlock()
