The game alternates between drawing even ID lasers and odd ID lasers each frame.
Galaxian game code#
To support the new laser limit, code was added to the laser drawing routine to flicker the lasers. In newer sets, each alien can shoot up to three lasers at a time. In older sets, each alien can only shoot two lasers at a time. Only the older Namco set and the Taito set let the player start with 5 lives.
Of course, each publisher has a different logo on the title screen. They seem to follow the chronology below: