surface(file = "", center = false, invert = false, timestamp = 0);
surface(file = "notfound.dat", center = false, invert = false, timestamp = 0);
surface(file = "notfound.png", center = false, invert = false, timestamp = 0);
surface(file = "surface.dat", center = true, invert = false, timestamp = 1444756256);
