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Comment by nartam11 | Hacker News Reader

How are the original computer opponents able to play MarioKart?

1. The AI in games has access to internal representations of game state and does not have to recognize it from pixels on screen. This is a massive difference.

2. The logic is usually a bunch of (human-authored) scripts consisting of if-else spaghetti.

Also, the AI opponents don't have to play by the same rules. They go by fun > fairness to keep things interesting. That's why you normally can't keep a huge lead on AI opponents, because they "rubberband" back up to you faster than they should be able to.

Wouldn't surprise me if they don't even 'drive' in any sense while off-screen, just increment some abstract position relative to the track length. But I don't know this for a fact.

How do you know this stuff? I find it insanely interesting.

Tell me more!

Mostly experience, but you should get plenty of results by just Googling "mario kart rubber banding". Looks like the top result mentions a patent on an algorithm for it, but I'm blocked at work.

It's a common enough term, though, there's even a page for the trope here:

http://tvtropes.org/pmwiki/pmwiki.php/Main/RubberBandAI

"Wouldn't surprise me if they don't even 'drive' in any sense while off-screen, just increment some abstract position relative to the track length. But I don't know this for a fact." This seems unlikely, especially given how item pickup zones operate. Since an item box disappears for a short period of time after someone drives over it, it's imperative that the position of the CPU player who drove over it, and the one that comes after that (and inherently gets no item) is represented accurately. Even off-screen, AI continues to collect and utilize items.

Then again, maybe this is just done by cheating simply with an RNG.

This is indeed what they do. Mario Kart 64 is known for having the most egregious rubberbanding ever.

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