AI Can't Recreate the Thrust Game (But It Can Help You Understand It)

AI Can't Recreate the Thrust Game (But It Can Help You Understand It)(jamesdrandall.com)

30 points by msephton 21 hours ago | 18 comments

iainmerrick 18 minutes ago |

Your reconstruction is so close, I'm a little surprised you didn't stick with the original controls! Even though the BBC had a rather weird layout for all the non-alphanumeric keys.

It's been a very long time since I played Thrust, and I've played plenty of WASD games in the meantime, but it still felt really strange to control it that way rather than the classic BBC Z/X/*/? for left/right/up/down.

Pretty sure it was return to fire, space for shield/tractor; and maybe * for thrust? Edit to add: ah, no, shift to thrust. Works very well on modern keyboards too.

jamesrandall 13 minutes ago | |

Maybe I should pop in an original keyset as an option - I think the original uses the caps key maybe. I'm pretty sure it's weird on a modern keyboard layout. I think the version on the bbcmicro site keymaps it by default, in any case if you want to revisit the original its here:

https://bbcmicro.co.uk/game.php?id=432

Edit: I'm going to have to go and revisit it again now... I was sure it was infuriating on a modern keyboard.

aenis 1 hour ago |

Funny. I had claude recreate Thrust based on wiki article alone - and it nailed it. I then spent a week trying to implement a perfect autopilot for it. And then a solveable level generator. I have this running as a screen saver in one of my apps.

AndrewKemendo 1 hour ago |

I tried to use his writeup to oneshot the game and you can see my results here along with the prompts I used:

https://kemendo.com/thrust-one-shot.html

Notably while the game "works" it's not even close to an a "reproduction" as far as I can tell - moreso an interpretation.

This has one level that doesn't level increment, none of the adversarial sprites are correct and the color and iconography are incorrect.

Granted I didn't give it much to work with but I figured I'd see what happens. As far as one shots go, I've seen worse.

I used commodity GPT 5.6 HIGH on firefox via chat interface

abtinf 1 hour ago |

> This is where things got interesting. Not because AI wrote the code — the code itself isn’t complicated, it’s a 1986 game that ran in 32K of RAM — but because Claude turned out to be an extraordinary tool for interrogating 6502 assembly.

Complaining about slop with slop.

not-a-llm 1 hour ago | |

> The tick loop waits at least 3 centiseconds per frame, giving an effective rate of about 33.33 Hz

3 centiseconds instead of 30 miliseconds, totally not a robot

SamBam 54 minutes ago | | |

Why would AI say that, when nearly every piece of training data is ever been fed would use milliseconds? I think much more likely that this is how the author thinks of it.

3 hundreds of a second == 33 Hz is very clean in my human brain.

spudlyo 1 hour ago | |

I was about to complain at you for jumping to conclusions, but your cited example contains two emdashes and a nested "it's not X it's Y". It certainly looks like slop. In my own writing I'm increasingly conscious of trying to avoid the appearance of slop, I would like to think I would have caught this.

jamesrandall 50 minutes ago | | |

For what its worth the article was a mix of things I wrote and things I asked an AI to generate from the notes I'd accumulated from the archaeology.

My focus was on the recreation - and getting it accurate was a lot of work (and a lot of fun). It's pretty easy to get an approximation (particularly if you just go with a standard physics model) but one that feels "off" if you played the original a lot.

slopinthebag 1 hour ago | |

A lot of people don't hate slop, they hate other people's slop. Of course their slop doesn't stink, they prompted it better or something.

iambenm 1 hour ago |

Hmm - the article isn't dated and it doesn't mention which models were used for the initial slop version. The initial commit in the git repo is from Feb 15, 2026.

I wonder how the initial pass would fare now with Fable 5 or 5.6 Sol?

jamesrandall 1 hour ago | |

I think it was Opus but can't remember the version. Would have been whatever was available in Claude Code in February.

Managed to find some screenshots. It did work but gravity wasn't really gravity - things fell at a constant rate. Turrets were floating in mid-air. It was missing the shields and you couldn't pick up the ball from the pedestal.

https://www.jamesdrandall.com/old-thrust/1.png

https://www.jamesdrandall.com/old-thrust/2.png

https://www.jamesdrandall.com/old-thrust/3.png

linsomniac 1 hour ago | |

I've been saying for months that any time you say something about the capabilities of the AI tooling you should say what exact model, agent, and effort level you're using. Because I've taken a few of those "AI can't do X" and had AI do a fine job at them.

I have Sol 5.6 ultra working on Thrust right now.

acbart 1 hour ago |

I'd be interested in seeing the "slop" version for comparison.

jamesrandall 55 minutes ago | |

Managed to find some screenshots.

https://www.jamesdrandall.com/old-thrust/1.png

https://www.jamesdrandall.com/old-thrust/2.png

https://www.jamesdrandall.com/old-thrust/3.png