FWIW my experience in gaming has been that Unity is exceptionally powerful and allows game developers to create games that would otherwise require an entirely separate dev team to support the engine. When I first learned game dev, the code sections were almost entirely devoted to interacting with the underlying graphics libraries (OpenGL or DirectX) and hardly any to creating powerful features in a game. Now, using something like Unreal or Unity is akin to using a web framework like Ruby on Rails or Laravel.
* The source is available to view and modify
I think you might mean that unreal is "source available" which doesn't confer any of the rights of open source, but does allow you to view and modify the source code subject to a commercial license (which might be free for personal, small scale use. I don't know unreal's pricing structure).
Unreal is not open source (cf. the Open Source Definition: https://opensource.org/osd/). It's just that the licencee is allowed to view and modify the source code within the limits of the licence.
Although, I don't even know if the KSP2 studio is big enough to afford it, let alone if they are actually doing it
> * The source is available to view and modify
“source available”, and then you are using common terminology in a non-controversial way and don't need an explanation that is longer than the term.
But if you want to do something a bit more complex, like modifying 3d objects in flight based on unit interaction, not only are you fighting an uphill battle, but the documentation is all out of date and mostly wrong. Because Unity isnt just an engine, its a set of default addons to that engine, and each of those addons was written to be just generic enough, but mostly just enable people to start making FPS and RTS games really quick. If you want to step outside that paradigm you are basically just engine coding again.
I’ve known people who worked on some games where they hand rolled a physics engine in c# instead of using the unity one.
I've been using Unity since 2009, and have been a lead developer and CTO in several different companies. I have never heard anyone writing their own memory management for Unity. May be you're talking about object pooling?
