One picture is worth a thousand bytes
By Dan Gutman
Of all the popular video game systems--Atari VCS, Intellevision, ColecoVision, Atari 5200--the Atari VCS is graphically the worst. It puts the fewest number of dots on the screen, fewest number of colors on the screen, and the fewest number of independently-positioned, movable objects on a line. However, thanks to heavy hitters like Space Invaders, Asteroids, Missile Command and Pac-Man in its library, the VCS has invaded millions of our homes. That staggering number has provided the incentive to turn the VCS into a machine that is now showing graphics that rival, and sometimes surpass, those of computers with three times as much memory.
Here are some of the graphics stars in my VCS collection.
- Ms. Pac-Man (Atari)--Although she is not nearly as spectacular as the arcade game, this cartridge puts Atari's VCS Pac-Man to shame. The field is a brilliant blue and you get a new maze every third wave. Ghosts, fruit, pretzels and Ms. Pac-Man are colorful, clear and realistic.
- Demon Attack (Imagic) -- Not only are your flying enemies incredibly detailed in the first wave, but they continually change throughout the game, all the way up to wave 85.
- Strawberry Shortcake Musical Match-Ups (Parker Brothers)--This game is aimed at little girls, and it is enjoyable just to look at the game's graphics. There are six Strawberry Land characters, each with a different three-piece outfit. A smiling sun sails across the sky to indicate the time remaining.
- Pitfall, Keystone Kapers, and Plaque Attack (Activision) --Activision is known for its superior graphics. These recent releases display such objects as shopping carts, escalators, snakes and packs of french fries--as tiny as two inches tall, but sharp and recognizable.
HOW DO THEY DO IT?
But if the ATARI 400 computer, for the sake of argument, has three times the memory capability of the VCS, shouldn't the graphics on games for the 400 be three times as good as games for the VCS? All other things being equal--yes. But other things are not equal. Although the 400 has the capability to display eight independently-positioned, movable objects on the screen (compared with five on the VCS), the VCS has something the 400 doesn't, called "repeat register." Repeat register allows an object on the screen to be duplicated indefinitely, with no extra drain on available memory.
For example, in Frogger, where you have an endless series of logs floating from one side of the screen to the other, the VCS designer (Ed English, for Parker Brothers) only had to code one log and put it in repeat register. The 400 designer, without the benefit of repeat register, had to use up a lot of memory to code each log. Virtually every VCS game has repeating objects, and this gives the illusion of a game that is more graphically complex.
Also, VCS designers have used their ingenuity to create games that match the graphic quality of computer games. One "trick" that is often used is a technique called "bank switching." The 6507 microprocessor chip in the VCS can only address a 4K ROM game. But if you put two 4K chips in the cartridge and instruct the VCS to look at one, then to rapidly switch to the other and back again, the system will, in effect, be playing an 8K game.
Games like Missile Command would look miserable if not for bank switching. Bank switching has not been used much with the 400 or 800 computer, only because each has enough memory so that it is not necessary to fool the system. Techniques like repeat register, bank switching, and simply "bludgeoning" a program to get every available byte out of it, have helped reduce the "graphics gap" between the VCS and the home computer.
LOOKING GOOD AND PLAYING BAD
There is no doubt that good graphics can improve a game. However, it must be remembered that great graphics are not synonymous with "great game." The 4K that is available to the game designer must fit all his or her graphics, sound and play action. If a lot of that space is used for the graphics, it will be necessary to sacrifice some sound and playability.
Last year, Atari released Earthworld, the first game in its "Swordquest" series. When you turned the game on, it displayed an incredibly detailed, multicolored sword that led you to expect a graphically superior game. However, the graphics on the rest of the game were rather ordinary, and, according to a reliable source, the sword itself took up 2K of the game's memory--one quarter of the total memory available just for the attract mode! You have to wonder what was sacrificed in play action in order to get that sword.
Video games are intended for interaction, not just observation. If the graphics are terrific and the game is lousy, the designer might as well take up painting. It is a very rare game that can display incredible graphics and, at the same time, give us exciting, action-packed play. Pitfall is one such game. The designer, David Crane, could have put less emphasis into the graphics of the game to make Pitfall Harry climb trees or shoot a gun. Instead, he chose to go with the good play action he had and make the graphics superior. These are decisions and tradeoffs that determine the quality of a game. Graphics and game play are a delicate balance.
Graphics are a large part of a game, but only a part. Two of the best video games ever, Space Invaders and Asteroids, were simple, straightforward, and black and white. But just as TV, movies, and photography were pushed inexorably towards better and finer color and resolution, so, we expect, will the market demand the same from computer graphics. In that line of development, the VCS is close to its limit now.