New Old Game: Gravi-o-roids!

Presenting a new old-school video game just a few years late, totally unironically.

Title illustation: arcade cabinet

Back in 2017, I was asking myself — like about every other person on Earth has done so before ;-) —, what would a Spacewar!-like game with multiple gravitational attractors look like? Would it even be playable? Well, time for an experiment.

Let’s see… So what could be excerting gravity with multiple appearances on the screen, well in the spirit of the setup? Hm… Isn’t there this game in Spacewar’s tradition, called Asteroids? What, if the asteroids were indestructable and would rather feature as wondering gravity wells? This might be interesting.
And, of course, have flying saucers as oppenents! I had done a simulation of Computer Space for the PDP-1 the year before and had just another try at the PET 2001, since it had been the 40th anniversary of the “trinity of 1977”. What, if we made the saucers Computer Space-style, and, as we are at it, maybe add guided shots, as well, just like in Computer Space? How well would these elements go together?

This sounded like a nice idea: A recombination of the most prominent of space shooters, which also represented a direct line of heritage: the very first digital video game, the very first coin-op arcade video game, which was heavily inspired by Spacewar!, and the famous arcade game, which finally accomplished on the mission of an attractive Spacewar!-for-one. Think, what if Nolan Bushnell had a PDP-10 at his disposal to put inside an arcade cabinet, instead of a glorified video pattern generator? And on top of this, we would get our gravity experiment. Which may be sort of a novelty, as well, as vector gravity games have fallen somwhat out of fashion.

It didn’t take long and I head a working prototype, including a live mapping of the gravitational forces in a small wire-frame display as the icing on the cake. The enemy AI is, BTW, just like in Computer Space, dumb, but effective. (Saucers move randomly and are just aiming in any of the 8 major directions, N, NE, E, SE, S, SW, W, NW.) — And then I had the brilliant idea to make this an actual arcade game, including an attract mode with autoplay (tuning the autopilot took longer than programming the actual game), highscore table, and a proper marquee (welcome Wacom tablet!), less coin-op. And then I ran out of steam. Also, the game was a bit taxing on more modest hardware (more on this below).

Gravi-o-roids!, screenshot
Mapping asteroid gravity as gravitational wells — see the top right of the display.
(The position of the spaceship is indicated by a bright dot.)

In 2019, I published an alternative, more orthodox version, featuring a single gravital star in the center and orbiting asteroids. A “Spacewar! trainer” allowing a single player to experience Spacewar’s mechanics, seemed like a viable idea. So there was “Outer Orbit”. (There you may see what has become of the world: had Spacewar! been conceived as a “spaceship trainer” in 1961, what it needed now was a “Spacewar! trainer”.)

Then, around last Christmas, I picked up the game again and reduced its internal frame rate. One of the reasons fo gravity games having fallen out of fashion is actually an effect of modern graphics APIs: calculating the effects gravity is an infinite, iterative process, and this is best done in discrete intervals of equal length. Modern APIs, however, are asynchronous and will yield a rendering function at random intervals. What is required, is an internal sub-frame mechanism, which runs time-slices of equal length on every call by the graphics stack. And this sub-frequency is desireably higher than any frame rate that may occur in real-life, otherwise an unequal distribution of these partial steps results in motion jitter. Which is, why such a game has to be more taxing on the hardware as would have been necessary a few years before. (Sadly, the fine-tuned autopilot for the demo sequence has suffered a bit from this, but you can’t have it all.)

Then I added sound and a few other missing bits and had an actual game, just missing the final packaging. And then I ran out of steam agian (probably a symptom of pandemic-induced lockdown syndrome).

Well, this week, I added a properly cheesy arcade framing to the presentation, which also separates this from its sibling, “Outer Orbit”.

And there you are, as I may proudly present, just 4 years late, Gravi-o-roids!.

Gravi-o-roids! with related artwork.
“Gravio-roids!” in all its cheesiness.

This represents actually a lot of layers of cheesiness: not only are we imitating an arcade setup in the browser, skeuomorphic interfaces like this are nowadays about as retro, as the game running in the virtual screen of the virtual arcade cabinet. Well, there you are. A new old-school game, in a new old-school presentation. (And woe betide you if you call me a hipster. This is entirely unironic.)