The original was very similar, but with minimum UI (no "Settings" panel), and it was just black on white line drawings, although I did add skid trails etc. after I'd got the core of it working.
Just the little bits of text glueing the (yes, machine generated) diagrams together as I recall, when I was indeed trying to finish the thing off in a bit of a hurry.
When you give even an inch to an LLM like this, people will assume you did it all like that. And it’s not a bad assumption given what’s out there these days.
As I said in the summary article, the core is a "textbook" 2D rigid body simulation (the "Brick" layer), and the Car bit is mostly a matter of deciding what forces are applied to the tyres.
In short, the tires "like" to go back and forward, but resist going sideways (relative to the direction they are pointing in).
The forces which are applied at the tyres are roughly equivalent to friction, but not quite (friction is stranger than many people think, and is not actually very velocity dependent). In some ways my tyre forces actually behave more like a form of "viscous drag" actually. I knew this was a bit dodgy at the time, and it was a sort of conscious "hack" that was chosen to produce "playable" behaviour as simply as I could.
Hey Pat, thanks for the write-up. I cannot get the car to oversteer, but unless I'm misremembering you could definitely do that in GTA. Any thoughts on what would need to change in your sim to support this?
It was probably just due to some parameter tweaks that were made during "tuning", especially when the game designers started making adjustments.
I'll maybe see if I can reproduce such changes eventually, but I'm going to be busy travelling from the next little while, so don't hold your breath! Sorry.
But the core text was hand-written, and the code faithfully represents the logic of the hand-crafted original from 30 years ago.
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