If you are looking of a free, cross platform, open source game engine that is already out and ready to use you should check out Godot: https://github.com/godotengine/godot
I'm all for a free and open-source alternative game engine, but the commercial engines are quite battle tested, and I've always thought of game engines as highly complicated pieces of software that can easily go haywire. Can anyone speak to the quality of the architecture of godot? (or even open source game engines in general, game engines are a subject I presume most are ignorant to).
As somebody who has worked in Unity for a number of years, I am really excited to trying out the new engine. Unity is incredible for rapid prototyping and pretty good at making certain types of games, but there is a lot of bloat if you don't use all of their systems. Seeing something more modular is super exciting, and I can't wait to try it out.
Unity and Unreal = Huge engine that can make life like multi-million dollar games. Can be overwhelming for small teams
Godot = Awesome engine where almost anyone can make a game quickly. Release a game in a week or you can work with a team for over a year with a polished game. Godot is the killer Indie Game Engine due to how easy it is to make a game but you can really get something that scales but it isn't as capable as Unity or Unreal.
Godot vs Luxe (Haven't programmed in Luxe yet) - Godot you really using a lot of menus to make your game, though you can now in Godot 3.0 do everything (mostly) code based now (Great thing in my opinion). Luxe seems to try and make it more code based with the ability to use menus and a API that will allow you to use almost any language (Though I think languages similar to Python with a ton of libraries might not be well suite for porting. I really think Racket would make a killer game scripting language if people will get over brackets.
The most painfully ironic example of a game that suffered from this is TIS-100, a game of optimising assembly for an imaginary ancient computer[1]. You can imagine how this completely ruined the immersion for me. I reported it to Zachtronics, and got a really swift reply. Maybe they managed to fix it since. All I know is that I'm happy that Shenzen IO used a custom engine.
Perhaps the bug is fixed in the newer versions in general, but I still see new Unity games come out that have this issue.
Until then, the workaround seems to be adding a manual VSync setting (Jazzpunk and Mousecraft both have this, and do not have this issue). So to any Unity developers out there, please add a vsync option. Not because you expect people to turn it off, but because making it a manual setting seems to fix this bug on Linux.