Dihedral Subgroups Explained Via Factorio

| Boris

The dihedral group is the mathematical formalism behind all the rotations and reflections of a regular polygon. For an n sided polygon, there are always n possible rotations, and n reflections, for 2n possible symmetries.

Combining any two symmetries gives another from the same group, that is what makes it a group in the mathematical sense.

The theory of it is useful to know for gamedev. I was reminded of this when seeing this Factorio devlog, where the developer ran into some trouble because he initially forgot to account for all the cases.

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Next Token Prediction is a Misleading Term

| Boris

I’m fed up of hearing about how LLMs are next token predictors, and therefore they <cannot do some task> <aren’t really doing cognition> <are just guessing>.

There’s lots of philosophical objections, but fundamentally, framing AI as next token predictors in the first places is just misleading and inaccurate. Here’s why LLMs aren’t naive next token predictors.

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The Lightyear Race

| Boris

Earth, proudly twinned with Rigel, went the joke.

When intelligent life on Rigel was first discovered, it was a sensation. The newly christened Really Improbably Large Interferometer had just picked up on the barest traces of radio signals from the planet. In mystery, there was speculation, possibility, hope.

As investigation progressed, every bit of information was a revelation. Rigel has an oxygen atmosphere! Rigellians must have discovered radio pretty recently! Rigel must get fantastic meteor showers from a billion year old lunar collision!

But excitement dimmed to the brutal reality of physics. At 1137 light years away, Rigel was to be looked at, not touched. We scanned, and listened and analysed every scrap of information. We broadcast, lasered and launched every signal and probe, of welcome and jubilation. But that was the end of it, there was nothing left to do but wait. We had to make do with a millennium-old image of our neighbors, who couldn’t have even yet received any indication of Earth’s existence.

We quickly realized we were still alone in the universe. For what does “alone” mean, if not “no one to talk to”.

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Good Software Doesn’t Double Check

| Boris

I’ve been wrestling with the balance between vibe coding and high touch manual coding these days. At the level of quality I’m trying to output, you cannot delegate everything to agents. But you want to do so as much as possible.

To do this effectively means developing a new set of coding smells. The original coding smells were quick tells of typical coding problems. They indicated muddled thinking, structural problems, or technical debt. But the sort of errors agents make are different and need a new set of nasal receptors. That is, for the next few months until a new crop of tools makes current wisdom obsolete again.

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Infinite Random Rectangles – the Poisson Rect process

| Boris

Previously, we looked at how to sample points randomly at a given density across an infinite plane.

It’s harder than it sounds, as I was looking for an algorithm that was not biased by the size/shape of the chunks used to calculate it.

Today let’s extend that to filling the infinite plane with random non-overlapping rectangles. As before, that means finding a deterministic chunked algorithm that we can prove is unaffected by the choice of chunking.

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My Trip to NeurIPS 2025

| Boris

I recently went to NeurIPS, the world’s largest academic AI conference. This was a multi-purpose trip: present a poster at the MechInterp Workshop and hobnob with other AI Safety researchers; get a general impression of state of the art in AI, particularly the gamedev/creative space, and represent Timaeus, the company I’ve recently joined.

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Silksong Quick Hints

| Boris

I’ve been enjoying Silksong a lot, but sadly it is not a game where you can trust the developers to leave good signposting and guidance. I don’t like to use game guides, so I ended up wasting a lot of time in this game, and then had to resort to guides anyway.

Here are some very light spoilers that will abate the worst of these. I’m not mentioning alternate paths, just things that the developers likely intended you to find, but might not. Collectively, I think this would have saved me 15 hours of pain.

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