Midway's version, which had a black-and-white raster monitor with a transparent yellow screen overlay, used bitmapped framebuffer technology to display the game text and graphics, including its animated human-like characters. To make the animation fast and smooth, the game included a special barrel shifter circuit built from multiple discrete chips. The microprocessor used this to shift each pattern of picture bits, byte-by-byte, to the proper horizontal bit offset, reading back each shifted byte and then writing it into the framebuffer. The 8080, like other microprocessors of its era, had shift instructions that could only shift by a single bit position. With the shifter circuit, the microprocessor could quickly shift a picture byte by several bit positions, giving it more time for other work. A similar shifter circuit was used in later Midway and Taito games whose hardware was based on "Gun Fight", such as "Sea Wolf" and "Space Invaders". (In some later "Space Invaders" derivatives, such as Taito's "Space Invaders Part II" of 1979, this circuit is a Fujitsu MB14241, a single-chip implementation of the barrel shifter.)