I started with Godot, and swtich back to Pascal. It will be and is cross platform, but I am focusing on Linux, because that is what I use.

With regards to Godot, while I like it, when using my own engine I can take a lot of shortcusts that Godot cannot. For example, I am able to save a lot of computational logic on reflections by making the requirements that reflections only world on right angled surfaces, which is fine for a pinball table. Also, I am able to cheap out with lighting using a my ouwn techniques for generating lighting maps in a shader, something that is hard to pull off with Godot.

This other game project of mine is written using Godot and C#:

https://www.orbliterate.com