Cytron Masters for Atari

by Dan Bunten

Cytron Masters is a “half-breed” game. It’s either a strategy game with action or an action game with strategic elements. Whichever it is, I (and my compatriots) initially wrote it for the Apple. As the game is entirely in machine language, and I had an Atari 800 collecting dust, I decided to “convert” Cytrons to the Atari. Sounded easy enough to me (and the other lunatics in my company)! After all, both machines have “high resolution color graphics”, both can do sound effects, both have standard game input devices (paddles and joysticks), and both use a 6502 processor. But what a difference a “generation” makes!

The Atari is the next generation computer (as compared to Apple) and it has all the features to prove it. I have been writing software for the Apple since 1978 and am just now getting to where I know how to make it sing. However, I found that sophisticated effects that require a lot of work on an Apple can be done with ease on an Atari.

Anyway, back to my story about “converting” Cytron Masters. This game is the result of almost eight months of development on the Apple and is an attempt to bring the “real-time” challenge of arcades to a strategic battle game. In the two-player version (solo is also available), each opponent can constantly create and order armies of up to fifty separate Cytrons (robots) on a battlefield which includes a number of capturable features. In addition there are animated fire-fights, fragment explosions and sound effects. I hope you can imagine the difficulty in writing a computer program that handles a hundred “intelligent” robots while processing “simultaneous” input from two players. As anyone who has attempted even a simple flash explosion with simultaneous sound can tell you, the Apple can’t do two things without a lot of effort (you have to time your clicks of the speaker with your graphic draw routine so that they take turns). It was a tough program to write.

After spending a great deal of time on the Apple version, I expected to just “duplicate” the same things on the Atari. (This being the tack that many Apple programmers have taken.) The Atari owners I spoke to, however, said. “It’s a neat game but where’s the color?” (Apparently Atari folks think you have to use five or six colors on a screen to qualify for “color graphics”!) Also, they wanted to know “What are those little noises?” — referring to the difficult to achieve explosion sounds. (Atari explosions are deep and resonating with a definite force behind them!) Finally, they didn’t like the “goofy little knobs” that Apple calls game paddles. (Atari owners love their joysticks.)

Needless to say, I decided that if the program was to do well as an Atari version, it would have to use a FEW of the features of that machine. But, during the conversion, I discovered that ALL the sophisticated hardware features of the Atari are useful! Cytron Masters uses the separate sound processor and four voices to make truly impressive sound effects (at least as compared to the Apple); it uses the Display List and Display List Interrupts to change colors on the fly. and have character graphics, four-color text as well as hi-res graphics on one screen; it uses Player/Missile Graphics for additional colors and fast animation; and most useful of all, it uses Vertical Blank Interrupts to allow two programs to (apparently) run at once!

All in all, the Atari is a fantastic game machine! It does have its bad points, such as an overblown (10K) and horribly slow operating system, a BASIC that’s more like Apple Integer than Applesoft, and a disk drive that’s reminiscent to Apple’s cassette in speed and reliability. But, for a game program in machine language that uses its own operating system (as Cytrons does) you can’t beat the Atari.

The Atari version of Cytron Masters was definitely an “upgrade” rather than a “conversion”!

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