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by typon 1764 days ago
It's really annoying how many people misunderstand the term 'data oriented design'. Usually to mean something like 'not object oriented programming'. If your data was inherently hierarchical and talking about animals that meow or moo, go ahead and implement the textbook OO modeling.

This Mike Acton post describes it accurately: http://www.macton.ninja/home/onwhydodisntamodellingapproacha...
1 comments
nikki93 1764 days ago
I do think that in practice a hierarchical ontology like that is still best not modeled as a language-level hierarchy because the language inheritance / hierarchy concepts are often not the exact semantic you want, IME. Esp. if it then ties to static types, since you then can't change the hierarchy at runtime. I think even with a data-oriented approach to a hierarchy -- your code isn't necessarily hierarchically organized, it just handles data that happens to express a hierarchy. And you want to be in control of the semantics of said hierarchy with more freedom (and explicitness) than the language-level hierarchy gives you -- so you want your own code that interprets the hierarchy expressed in the data and performs your desired semantics. This also allows artists and narrative or gameplay / level designers to go see and edit the hierarchy and add elements to it.

An example is the prefab hierarchy you get in Unity, which is expressed through the data (prefabs and their relationships). (Note: I mean specifically the prefab inheritance hierarchy, not the transform spatial hierarchy -- the former has more overlap with the "is a" relationships). The code processing this hierarchy could've just been plain C code that parses the files and maintains an in-memory set of structures about them, even. You then get to define how properties inherit, what overriding means, etc. yourself.

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typon 1764 days ago
Totally agreed. The fact that some of these concepts are embedded into the language design (say for C++) are minor conveniences at best - when they almost perfectly line up with the data you have - but just get in the way most of the time.
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