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Comment by bogwog | Hacker News Reader

I know what you mean, and that confusion is 100% Unity's fault, because they call their data-oriented entity system "ECS".

Back in the day, composition was referred to as "component-based entity systems", which makes perfect sense.

But then Unity came in and called their data-oriented one "entity component system" for reasons I will never understand. Why not just call it "data-oriented entity system" or something like that?

So nowadays when you hear "ECS", it's not clear what people are talking about anymore.

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The confusion is worsened by people interpreting it as "[an] (entity component) system" or "[an] ((entity) (component)) system", when it's actually "[an] Entity–component–system [architecture]". That is, it's not a system of entities and components, it's an architecture comprising entities, components, and systems.

it's not surprising given that "entity component system" is synonymous with "thing behaviour environment". It's using the most meaningless generic terms possible. It's like when companies use a tagline like "using innovative practices to deliver results for our clients".

I'm not sure Unity is at fault here. Most people in the game dev business knew about what ECS is (Entities + Components + Systems) long before Unite Austin 2017 (when Unity first announced their upcoming entities package).

It would be fair to attribute the ECS naming (specifically, making "Systems" an integral concept to the, ahem, system) to this from 2007: http://t-machine.org/index.php/2007/11/11/entity-systems-are...

I would say it is 100% not Unity's fault. As someone else posted, there's a t-machine blog posted and that entire blog has been filled with ECS with that specific term for years. But aside from that it has been a heavily discussed thing for many years in the gamedev scene. There's a wikipedia page on it, showing a bit of history from well before 2017, but you will find most on it on gamedev.stackexchange and gamedev.net. It probably predates the start of Unity in its entirety.

Also, to be fair, they really do refer to it as DOTS -> Data Oriented Technology Stack (granted, it includes more than just that), but I'm not sure if and when they changed that. Their community just seems to keep calling it ECS regardless.

DOTS is not ECS. "Unity Classic" is ECS. DOTS is a more cache-efficient architecture designed to support larger numbers of entities.

Unity's DOTS is definitely an ECS system. You technically can have an ECS without all the data-oriented and cache efficient stuff, if you just want the architectural benefits, but it's pretty hard to build a data oriented game engine that is not fundamentally ECS

Definitely true, having looked at probably 20-30 ECS frameworks in about 5~ different languages between 2019 and 2020. About half of the ones I looked at, probably a bit less, were DOTS.

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