building a city - workflow and optimization

Hello everybody

This is my first post here and I am completly new to unreal or any other game engine, while I have quite a lot of experience in 3D

One of my students is developping a medieval city in Unreal as his graduation project. We are not a game department, so for the engine part we are pretty much exploring the thing together. He doesn’t speak english, so I am asking for him.

For modeling the buildings (outside only), I advised him a modular approach:

1 - model wall and roof sections, with or without door, windows, beams, chimneys, towers and other stuff he has in his design.
2 - combine them to make a variety of buildings from a minimal variety of models

Then what would be better ?
a - Export/import the modular buildings as one object each and instance them in unreal
b - Exports/import the wall and roof sections as different objects and place them as different objects in unreal - this seems better to me from a polycount viewpoint but a nightmare in scene management…

For the materials is that ok to have 3 UV channels on most of those objects : one for a repetitive brick or stone pattern, one for layered large patterns such as paintings, graffitis, rain marks and such, and one for global illumination ?

I hope my questions make sense ?

Thanks in advance


Sounds fun, it might be worth looking into blueprints and having the modular pieces or buildings/wall sections instanced through there and potentially even procedural generate them for ease of placement and to prevent a repetitive look.

He could also create ‘prefabs’ bring in a load of modular pieces, build 5 or so different houses them combine them. See here (
Then using a blueprint to place those prefabs?

Either way it sounds like you have the general gist, I personally would just have 2 UV’s 1 for texture 1 for lightmass and use vertex blending to add dirt and decals to have the finishing touch.

Thank you very much !

I don’t think he will go for the blueprint option as he is still struggling with much more basic things like modelling and UV mapping - but I will check myself.

As a general rule, is that better to have lot of smaller objects, of fewer bigger objects ? Does that impact performances ?


Its better to have smaller modular pieces in Unreal, because then you can combine them to different looking houses without extra cost (static meshes are stored only once on the graphic card, no matter how often you use them or how those are scaled/rotated, mirrored for different use in the map).

I believe small modular pieces would be a better option. Look at Medieval Village by Poly Pixel as an example;
You can easily create stuff with a couple of meshes rather than building a complete model and export it everytime