One of the first video games with a procedurally-generated soundtrack is Ballblazer, a simple first-person soccer-like sports game originally released by LucasFilm Games for the Atari 400 & 800 in 1985. The music engine was written by Peter Langston, a programmer and player of “anything with strings on it” (guitar, banjo, etc.). He’s described the music in papers and such; essentially the algorithm just glues a bunch of predefined riffs together, with some minor random modifications for variety and a little smarts in arranging them with accompaniment:
The riffology algorithm makes dynamically weighted random choices for many parameters such as which riff from a repertoire of 32 eight-note melody fragments to play next, how fast to play it, how loud to play it, when to omit or elide notes, when to insert a rhythmic break, and other such choices. These choices are predicated on a model of a facile but unimaginative (and slightly lazy) guitarist. A few examples should illustrate the idea. To choose the next riff to play, the program selects a few possibilities randomly (the ones that “come to mind” in the model). From these it selects the riff that is “easiest” to play, i.e. the riff whose starting note is closest to one scale step away from the previous riff’s ending note. To decide whether to skip a note in a riff (by replacing it with a rest or lengthening the previous note’s duration) a dynamic probability is generated. That probability starts at a low value, rises to a peak near the middle of the solo, and drops back to a low value at the end. The effect is that solos start with a blur of notes, get a little lazy toward the middle and then pick up energy again for the ending. The solo is accompanied by a bass line, rhythm pattern, and chords which vary less randomly but with similar choices. The result is an infinite, non-repeating improvisation over a non-repeating, but soon familiar, accompaniment.
Langston had a somewhat critical assessment of the results of this algorithm, noting in the same paper that it wasn’t interesting music because “the rhythmic structure and the large scale melodic structure are boring.” Other reviewers were kinder to the soundtrack, though, with Langston quoting Pat Metheny in another paper as saying “it sounds like John Coltrane!”
Well, that review might have been just a tiny bit self-serving, because it turns out that Metheny actually contributed to this whole riffology business. I’ve known about Ballblazer for a while; I first read about it in KC Collins’s book Game Sound, which quotes the same Langston paragraph I did above, and since then I’ve seen it mentioned as historical trivia a few times. However, what I wasn’t aware of until now, because no one ever mentioned it, was that Langston didn’t actually write all of (any of?) the source riffs himself. I assumed he did, but he didn’t! He credited the musicians who did in the first paper:
Credit is also due to fellow musicians who were excited by the idea of computers improvising music and contributed riffs: Steve Cantor, Mike Cross, Marty Cutler, Charlie Keagle, David Levine, Lyle Mays, Pat Metheny, and Richie Shulberg.
Most of these folks are bluegrass musicians like Langston, but then there’s uhhhhhhhhhhhhhhhh Lyle Mays and Pat Metheny in the middle there. Yeah.
There’s a little bit of ambiguity in the paper on which of these contributors’ riffs made it into Ballblazer specifically, since the paper also talks about Langston’s further development of the riffology algorithm for a phone service you could call into to listen to randomly generated music, for which he added more riffs to the database. But game historian Andrea Contato interviewed Langston as part of a piece on earlier computer music experiments from the 1960s, and he quoted Langston saying that Mays’s and Metheny’s material was in the game:
The improvisation uses snippets of music contributed by a number of friends. Pat Metheny and Lyle Mays contributed some material, and Doc Watson contributed something as well. Part of what makes it so compelling is that it includes small fragments of music from great musicians. That was also built into the game’s backstory: each year, whoever wins and becomes the “Master Blazer of the Year” gets to contribute a fragment of advice in the form of a musical phrase. That phrase then becomes part of the Song of the Grid.
So, Metheny/Mays VGM real???????
(hat tip to marklincadet for finding and posting this in the VGMdb Discord)
Leave a Reply