I'm excited to announce the first release of my library, evolved.lua!
evolved.lua is a fast and flexible ECS (Entity-Component-System) library for Lua. It is designed to be simple and easy to use, while providing all the features needed to create complex systems with blazing performance.
> Components are stored in contiguous arrays in a SoA (Structure of Arrays) manner, which allows for fast iteration and processing
Does this actually matter in Lua? Aren’t all array elements going to be pointers to heap allocated objects anyways?
The point of SoA is your likely to be accessed values are adjacent in memory, but if you’re chasing a pointer to get that value then you’re not getting anything out of it.
Yes, organizing components as SoA can provide a significant performance boost in Lua, especially with LuaJIT. Both iteration and element access become faster, and it also reduces memory allocations and GC pressure when creating entities. And yes, Lua tables can be contiguous in memory if you use them carefully.
Comparative benchmarks are a big task on their own, and usually the author's library wins in them. I have internal benchmarks in the repository, but they are not designed for comparison or for evaluation by outsiders. Maybe I'll get to that someday.
Lua uses tagged unions so that primitives are stored inline within a table. Some time ago I benchmarked this and the perf gains from SOA were significant. Besides, even if you had to chase pointers, SOA still means you can reduce the number of allocations.
Cool to see a new ECS project! I've been learning and using JECS (https://github.com/Ukendio/jecs) for a project of mine, and some of the core ideas (like Chunks) felt familiar. This project definitely seems to have a more in-depth documentation though and a lot more features especially by having its own scheduler stuff. Would love to try it out on a new project someday
Will give this a try. I was using claude code to make a small game in love2d, and really hoped for a nice lua ecs lib to help manage the game objects (its my first time playing around with game dev).
Not yet, but I wrote this library to use in a project of mine. When I finish it, I will add a link to the README. As for a small demo project, I have one in mind, but I haven't started it yet.
Does this actually matter in Lua? Aren’t all array elements going to be pointers to heap allocated objects anyways?
The point of SoA is your likely to be accessed values are adjacent in memory, but if you’re chasing a pointer to get that value then you’re not getting anything out of it.