Do game developers build custom game engines just for a single game or a game franchise?

Question

I am aware that game engines like Unity, Unreal, Cry Engine provide almost all the tools necessary to build an AAA title game. Its also the best choice if the game has a tight release data or if your new to game development. But since they are generalist game engines (meaning that they are made to fit multiple genre of games. Correct me if in wrong) for some games (next-gen or games which require a lot of performance), they might leave some performance on the table, something which could be accomplished by developing a custom engine.

This brings me to my question,
Do game developers (indie game developers, large teams or even companies) still build game engines from scratch to tailor fit a game or a game franchise?

Thank You!

Answer 1

when we talk about big companies like Ubisoft or rockstar they built their own engines and didn't use Unity or unreal

Rockstar uses "Rockstar Advanced Game Engine" and Ubisoft uses "AnvilNext"

but why?

there are millions of reasons they do such a thing, I'm gonna say just 2 from @scremyCat

the support

and the license

1. Support: Highest degree of support and understanding - as they built it all, they understand all of its internals and can offer complete support. E.g. A game needs X feature, they'll easily know if they can implement it or not. Another benefit of this is not having to wait on external entities, if there's a game breaking bug in the engine they can get right on it, while a third party engine depending on the licensing agreement this might not be possible (though they would typically license the source code anyway).
2. License: Licensing - as an indie developer accepting that you might have to pay a small percentage of your revenue for licensing the engine might not be as much of an issue seeing as the amount you need to breakeven is unlikely going to be very high and chances are you're already making when your revenue is at the levels needed to pay a %, and your total revenue from a game isn't likely going to be huge anyway so the amount in licensing fees you need to pay may seem very reasonable. Meanwhile a AAA game will have a much higher break-even target and their expected revenue is most definitely in the tens to hundreds of millions, which now means they're paying a large amount in licensing fees. Now it should be said they usually get much better licensing deals to begin with than the indie dev gets, but still they're paying huge amounts.

As for timeframe, it can take years to fully develop an engine of their scale. Often why you'll see them using the same version of the engine for a good cycle of games whilst working on the next version of the engine. And as for what's involved, a LOT. They need to handle every platform they'll be targeting, the rendering, the physics, the AI, the audio, the input, the file system access, the asset management pipeline, the tools, etc.

How are they better than current popular engines? They aren't necessarily (to other developers), but to them with their own reasoning for doing it they are. The simplest answer for how can they be better is that when you're creating your own engine from scratch you can do whatever you want.

It should also be said that developing your own engine isn't just limited to large game companies, a number of smaller developers also do this. The more popular reasons for this are typically because they enjoy it, and have some functionality they want that isn't available in existing options. E.g. While you can create many games with Unity or Unreal, there's plenty of things which just aren't feasible or might take considerable work to even make possible anyway. This can be a reason for a smaller dev to make their own engine.

Answer 2

Yes, they absolutely do. Nintendo is a good example.