Better to use single or multiple models?

Questions & Answers
1

I’m creating an apartment building that has three floors and six suites on each floor. Every aspect of the building will be explorable. I can’t remember where I saw it but someone said to separate models for better performance. So I’m wondering if this is true. Right now I have it all combined as a single model. Should I maybe separate the individual suites and also have each floor separate?

2

My understanding is that unity only culls whole objects, not meshes or submeshes. So this means you would have to divide your building into separate objects if you want to increase performance. I think Unity will automatically import your model as a hierarchy of objects if you divide it into separate meshes in your modeling program.

There are more details in the answer to this question:

http://answers.unity3d.com/questions/9115/frustum-culling.html

If you have Unity Pro you will get even more performance increase by splitting your model. You can read about how unity culls off-screen objects here:

https://docs.unity3d.com/Documentation/Manual/OcclusionCulling.html

Also read up on batching here:

https://docs.unity3d.com/Documentation/Manual/DrawCallBatching.html