Bushnell and Dabney weren't the only ones to try to market a coin-operated version of Spacewar!. A more successful effort came in 1977 with Larry Rosenthal's Space Wars. Rosenthal had been a student at MIT where the original game had been developed, and felt that he could do a better job than the earlier efforts at converting it for arcades. However, he demanded a full 50% of the profits, and only the floundering Cinematronics was willing to accept his demands.
Rosenthal's key innovation was developing a special processor, which was cheap to make yet still sophisticated enough to run the full version of Spacewar!, complete with the gravity well and two-player dog fighting that made the original so compelling. It also offered other innovations, such as the ability to take some damage before exploding. Players could adjust the gravity and inertia of the game world as well. Gameplay was strictly time-based; whoever had the most kills at the end of the match won the game.
Perhaps the game's most important feature was its vector-based graphics, which made it both more faithful to the original and better-looking than Computer Space's raster graphics had been.
The essential difference between vector and raster graphics is that the former are based on lines instead of dots or pixels. Vector graphics tended to look much sharper than the raster games of the era. In the end, it was a wonderful adaptation of Spacewar! and earned rich profits for Rosenthal and Cinematronics.
In 1978, Atari released Orbit, yet another raster-based adaptation of Spacewar!. Unlike the previous effort, however, this one at least offered two-player side-by-side play out-of-the-gate and borrowed the partial damage system of Space Wars.
Perhaps the only really interesting aspect of the game is that the ships now looked like the Enterprise and a Klingon Bird of Prey from Star Trek. The game wasn't a hit and is rarely spoken of today, though a simplified home version for the Atari 2600 VCS was released in 1978: Space War.
Screenshot from Atari's Orbit.
Box back from one of the many early home games that took inspiration from Spacewar!, Fairchild's Space War (1977) for their Video Entertainment System.
Atari went vector skelter in 1979 with Lunar Lander (also discussed in book Chapter 8, "Flight Simulator (1980): Digital Reality") and Asteroids, two stunningly innovative but notoriously difficult games. Lunar Lander, as the name implies, had players carefully landing a lunar module on one of several moon bases (platforms, really).
What made the game so challenging was its painfully realistic physics: players had to work hard to generate just enough thrust to maneuver the lander and resist gravity. Fuel was at an absolute premium; running out meant almost certain death.
This game was eventually ported and cloned on home platforms; former Commodore VIC-20 owners may remember the clone Jupiter Lander (1981), for instance. The gameplay concepts introduced in Lunar Lander would later evolve into the many "gravity" and "thrust" games of the 1980s, including Atari's aforementioned Gravitar in 1982.
Screenshot from Atari's Gravitar.