JaiPrimer VS entt

The first and most important step is having a language without statements and only expressions.

But, as Jai needs a `return` in functions, it already failed the trivial test.

https://github.com/BSVino/JaiPrimer/blob/master/JaiPrimer.md

Thanks, and yes, I didn't think about closures.

Talking about closures, I also don't know why Jai needs explicit capture lists. In C++ and Rust I understand the need for them, because you have various ways to pass them into the lambda, but Jai doesn't seem to care, at least in the examples at https://github.com/BSVino/JaiPrimer/blob/master/JaiPrimer.md....

Jonathan Blow & co will probably be busy enough trying to release Braid: Anniversary Edition this year (it will be Braid's 15th anniversary this August), and this will push the release of untitled-Sokoban-game until 2024 or later. Note also that the sokoban game is intended to promote the new programming language he is creating (https://github.com/BSVino/JaiPrimer/blob/master/JaiPrimer.md), so that might slow development / delay the release of the game beyond what would be expected for a normal videogame. (Ie, it's not just the sokoban game that needs to be ready for release, but also perhaps other features of the new language.)

There's quite a lot of information, just not very accessible.

https://www.twitch.tv/j_blow/videos?filter=archives&sort=tim... : this is jai's author livestreaming language development, most up-to-date

https://www.youtube.com/playlist?list=PLmV5I2fxaiCKfxMBrNsU1... : a cureated subset of twitch videos, possibly outdated info

https://github.com/BSVino/JaiPrimer/blob/master/JaiPrimer.md : a summary of jai based on the above curated videos, possibly outdated

The Jai language is the main competitor to C++ I feel. The compile times are insanely short, which is what slows you down the most when actually developing a game in C++ Unreal.

There has been a lot of hype about the Jai programming language (for game development), but another language that has been heavily influenced by it and has a lot of similar syntax and concepts is Odin. Here is a blow by blow comparison, Jai vs Odin.

This reminded me of Jai, the language by Jon Blow. In the Primer here: https://github.com/BSVino/JaiPrimer/blob/master/JaiPrimer.md, the section on Data-oriented design is relevant. Note that the bottom of the OP article mentions explicitly the games industry as caring about this; relevant given Blow's background.

Look for "Data oriented design" or "Structs of arrays".

Here's a talk on the former by Mike Acton: https://www.youtube.com/watch?v=rX0ItVEVjHc

On the latter, there's Jai, a new programming language for games (WIP, unpublished) by Jonathan Blow, who has been very public in documenting the process creating it, and which is centered around such concepts. There is some unofficial documentation of the ideas on SoA vs AoS and how the language can help switching between the two, e.g. here: https://pixeldroid.com/jailang/overview/Features/SOA/#/overv... and here: https://github.com/BSVino/JaiPrimer/blob/master/JaiPrimer.md...

Isn't that still the very thing that is done in various game engine entity component systems? Interestingly Jai language has out of box syntactic support for handling structs of arrays vs arrays of structs https://github.com/BSVino/JaiPrimer/blob/master/JaiPrimer.md#data-oriented-structures

EnTT is a popular alternative to flecs for C++, which has different performance/memory characteristics.

https://pastebin.com/VPypiitk This is a very small experiment i did to learn the metaprogramming features. its an ECS library using the same model as entt (https://github.com/skypjack/entt). In 200 lines or so it does the equivalent of a few thousand lines of template heavy Cpp while compiling instantly and generating good debug code.

Some walkthrough:

Line 8 declares a SparseSet type as a fairly typical template. its just a struct with arrays of type T inside. Next lines implement getters/setters for this data structure

Line 46 Base_Registry things get interesting. This is a struct that holds a bunch of SparseSet of different types, and providers getters/setters for them by type. It uses code generation to do this. The initial #insert at the start of the class injects codegen that creates structure members from the type list the struct gets on its declaration. Note also how type-lists are a native structure in the lang, no need for variadics.

Line 99 i decide to do variadic style tail templates anyway for fun. I implement a function that takes a typelist and returns the tail, and the struct is created through recursion as one would do in cpp. Getters and setters for the View struct are also implemented through recursion

Line 143 has the for expansion. This is how you overload the for loop functionality to create custom iterators.

The rest of the code is just some basic test code that runs the thing.

Since we wanted a common game simulation that would be on both the server and the client we looked into a few libraries that would fit our ECS needs. It was decided we were going to write this common part of our game in C++, but rust was considered. C++ was a familiar language for us so naturally EnTT and flecs came up right away. I had used EnTT before, writing some small demo projects, so our choice was made based on familiarity. In order to integrate with Unity we created a small C interface to communicate between our simulation code and Unity’s C#. Here’s close to what it looked like. I removed some parts for brevity sake.

Are you sure you don't want to use a C++ package manager? Libtcod is on Vcpkg and with that setup you could add the fmt library or EnTT. fmt fixes C++'s string handling and EnTT fixes everything wrong with the entities of the previous tutorials.

There's also a performance question. While we can now use Blueprint nativization to convert Blueprints to C++ the result will be a fairly naive version, fast enough for most purposes but not if you're trying to push every bit of performance. This is where you're looking at making sure you're hitting things such as using the CPU cache as well as possible for an ECS system (Look at ENTT or Flecs if you want to see what they're about and why you'd want one), or a system needing to process massive amounts of data quickly such as the Voxel Plugin.

For a modern engine you’re probably best looking at Unity’s DOTS. You may also want to check out some of the different open source ECS libraries such as flecs and EnTT are two popular ones for C++, but there’s lots of them. Largely you’ll see lots of different approaches taken, all with their own pros and cons. Not all of them will be performant (some focus more on the design benefits) while others will be optimised for certain use cases. What you should prioritise will depend on your specific needs.

You can think of DynaMix as combining one of these libraries with an ECS like entt(https://github.com/skypjack/entt)