Copy data to each entity or reference entities?

Unity Engine
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1

I often have a problem of the following kind:
Entity Human has a Profession and Profession has many GoodProduction.
Therefore Human (one to one) Profession (one to many) GoodProduction.
There will be a few hundred Professions and GoodProductions at most whereas I want the game to scale as big as possible in Humans.

The Human often needs to reevaluate which Good he should produce next. I have two options:

(A) Let the Human have a Profession component (linking to the Profession Entity) and the Profession have a GoodProduction-Buffer (not linking to entities but containing the actual data)

(B) Directly copy the GoodProductions to the Human Entity when he enters a certain profession. When the Human changes Profession, change this GoodProduction buffer.

The second option (B) allows me to have an actual linear data layout when I the “Evaluate which good to produce” system runs. On the other hand it will increase the Human Entity size by probably 8-24 bytes and will produce redunant data. Option (A) is more of a normalized (database) layout but I will always have to have random access to the Profession entities.

I have had similar decisions before**,** always of the kind “If my Entities share some data, should I copy it to the Entities or should they just link to another Entity that has their shared data.”

2

You only stuck at solving DOTS structure data layout.
Draw it in uml style visually might help https://www.draw.io/ or not

Go with B
Entity Human: Human tag, Profession tag, GoodProduction-dynamicbuffer (no need to worry about micro entity memory)
When change Profession, add ChangeProfessionTagToComponent to human and have a system query it then do whatever you want with dynamicbuffer

And do not use shared component data here. You only confuse and mix them up. Use Tag.

3

this way they will be grouped by profession and it will not be random access anymore

4

Yes. Basically (A) is how I think a database layout should look and how I avoid redunant data. (B) has linear access but makes the entities bigger.

I have also thought about this but I think I do not want to go down that route yet. If I now start using SharedComponent for Profession, I group them by profession. Later on maybe I want to also group them by the Village they live in (which makes other systems have linear access) or their corresponding “Wealth class”. I wanted to wait until the end to decide which systems are the heaviest and which components therefore will be SharedComponent. I do not want to use SharedComponent for everything, as then I will have very small chunk sizes.