Simulating Infinity in Conway's Game of Life with Modern C++

ofrzeta•about 3 hours ago

"I had heard the rumors that C++ was a scary language filled with footguns and segmentation faults, but I had never given it a fair chance myself" - props for this. There's too much hearsay in software engineering.

fc417fc802•about 2 hours ago

And then immediately afterwards we see const T* in a supposedly immutable data structure meaning the pointer remains mutable. Yet another classic footgun.

mooreat•about 1 hour ago

It looked to me like most of the raw pointers in the blog were const. Sometimes you don't want the baggage of smart pointers and getting a cheap easily copyable view of your data is nice, so you want to return a const T. Usually if an API returns a const T I assume lifetimes are handled for me and that the ptr is valid as long as it is not nullptr.

eps•about 4 hours ago

Small nit, this - https://ryanjk5.github.io/assets/2026-05-14-GOLDE/torus.gif - is not what's conventionally referred to as a torus in CGoL. In torus left and right edges are also connected.

xeyownt•about 3 hours ago

Yes, it's more an infinite cylinder.

jdw64•about 6 hours ago

It seems like the thread_local CacheIndex only determines which cache to use, but it doesn't actually guarantee thread safety for concurrent access to the HashLifeCache itself. What would be a good solution for this?

Should I use a mutex for each cache instance? As a beginner developer, my guess is that the original author assumes data races won't occur based on the execution timing. However, I'm really not sure if that assumption is actually correct/safe.

nnevatie•about 2 hours ago

In my view, thread_local is a bit of a code/design red flag. I didn't read the entire code in this case to see whether the thread_local use is warranted or not, though.

gpderetta•38 minutes ago

a thread_local is just a global variable. Mutable global variables are of course bad, but in this case the threadindex is immutable once created, so it is perfectly fine.

hiroakiaizawa•about 4 hours ago

Interesting approach. I like that the implementation focuses on scalability rather than only visualization.

ontouchstart•about 1 hour ago

This would be a cool template project to learn C++ without the pollution of LLM slop.

classified•about 5 hours ago

Fricking cool, I love it.

Simulating Infinity in Conway's Game of Life with Modern C++

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