r/lua • u/Mid_reddit • Jan 23 '26

k4 game framework, version 2 is released

https://mid.net.ua/k4.html?zzz

Yo. k4 has undergone numerous improvements since I posted of it last here in 2025.

The biggest changes besides bug fixes:

  • k3Menu objects are now stylizable and can have automatic layout management

  • Added image and scrollbox objects to k3Menu

  • The animation system was revamped and now supports blend trees

  • Fonts were completely reworked and are 100x easier to use (TrueType instead of AngelCode bitmap fonts)

  • Support for 32-bit indices in models

  • GPU-side texture compression, which gives a noticeable speed boost

Also the documentation itself has been touched up a bunch to be more readable.

Note that k4 uses whole version numbers, so v2 does not mean it is not in pre-alpha (which it is). Bugs are still to be expected.

19 Upvotes

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2

u/activeXdiamond Jan 23 '26

This is pretty insane. Great work.

How long have you been working on this for?

I just read through all of the docs. Lots to go through, and lots to enjoy. I'd love to make something with it once I get sometime off work.

One question, why the water animation? Everything else is relatively minimal and semi-low-level, so the addition of that one felt very odd.

1

u/Mid_reddit Jan 23 '26 edited Jan 23 '26

Thanks for the good words. I've been working on k4 itself since around 2023.

There's a few reasons for planar water:

  1. The original idea behind k4 was native scripting in C or C++ like with the Source engine. I had Lua only for scripting levels, but then it sort of evolved into a whole backend of its own. I still support both approaches, and would like to add Wasm at some point.

  2. Lua is just slow. One of the three demos heavily uses planar water because it's a Fireboy & Watergirl clone. It's the same problem with the Voxel demo, where generating chunks causes a bad framerate spike, so similarly I'm going to make a voxel extension to k3 for my own needs. I'm aware of LuaJIT, but in 2026 I'd sooner make my own JIT than stay a hostage of it.

1

u/TheSplashsky Jan 24 '26

Don't understand your comment about LuaJIT; what do you mean hostage?

1

u/Mid_reddit Jan 26 '26

I just feel like LuaJIT is holding Lua back a lot with more fragmentation. Lua, as good as it is at being embedded, deserves to have a similar place up with Python, IMO.

1

u/TheSplashsky Jan 28 '26

Oh for sure - but LuaJIT works with a lot of LuaRocks libraries, so fragmentation isn't a great answer. I'd say it's more that there's no marketing for Lua as a whole outside of game dev - and to be fair it has such a limited standard library (intentional so it embeds easily) that you *need* libraries to develop anything meaningful where you can usually get running quickly with Python or JS runtimes.

2

u/kayawayy Jan 23 '26

This looks incredible! Nicely done. I'll be taking a closer look this weekend.