Proper Way to UV map a big model?

The model here has too many of everything

What is the right way to do this?

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What is the model for? Game, film, illustration? There are many ways to do it and they depend on what is the purpose of the asset.

Game. Cities Skylines

Then you would never unwrap this uniquely to a 0-1 sheet(or any large non-modular environment model) It’s a huge background asset. Tiling textures. Atlasing.

Can you recommend any Blender UV mapping add-ons, Dan? I’ve always tried to avoid UV unwrapping hassle through the years, but I really need to do it for a job I’ve got at the moment. Is there a Blender add-on that makes unwrapping as easy as UV Master, or should I return to good ol’ ZBrush for UV Master?

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I’m one of those weirdos who love unwrapping, Metin. :crazy_face: 80% of my unwrapping work is hard-surface. I take it you’re unwrapping organics? These days with 3D texturing/triplanar it really doesn’t matter as much. UVmaster is great for those quick and dirty unwraps, and as you know, you can control it with polypaint/polygroups. Substance Painter even has an auto-unwrap like UVM now.

For organics, you can cut your islands up much more freely because of 3D texturing. What type of job are you doing? Don’t you usually do cartoon/stylised/organics? I’ve only unwrapped once in Blender, but it was a big asset - hard-surface with 100 parts, so I haven’t looked into addons for organics. I have Rizom 3D for organics so I’ll cut all my seams in Max or Blender and just unwrap/relax in Rizom.

The addons I use in Blender that I find essential(bear in mind this is hard-surface game assets) are Textools, UV Highlight, and the AMAZING UV Packmaster. This last I bought the pro version the moment I decided to use Blender to unwrap and it is phenomenal. It saved me days of manual packing.

I’m not aware of any addon that auto-unwraps organics like UVM.

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I have experience with modding for Cities: Skylines so I can help.

Firstly, I highly recommend reading this guide on Steam because it is very useful and has all the information, if you haven’t already: https://steamcommunity.com/sharedfiles/filedetails/?id=500036497

You are really stuck with a single UV texture. The game does not recognise assigned materials or anything, just the textures for it. That means you are going to have to get all the textures onto a single image (which would be having dimensions of powers of 2, e.g. 1020, 2048 pixels). For a large and highly detailed object like that, I would suggest using a 4k texture (4096 pixels), and putting all the parts onto it.

Now also, tiling is impossible for the game textures here, so you cannot get the UVs beyond the range of the texture. This is because the game stores all the loaded textures into atlasses for quicker access, so it is essentially a giant texture with the smaller textures placed within in a grid. Making the UV any larger (to make it tile in Blender) would result in the neighbouring textures being used instead on the texture atlas.

Now, if 4k is not enough, you could create props separately for other details and keep the building’s texture as just the basic parts (e.g. walls, roof).

Cities: Skylines worka a bit different to other games, so UVs beyond the texture’s size would not create tiling.

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Thanks, I had no idea what cities:skylines was(until now) :slight_smile: OP’s response wasn’t giving much away and just assumed I knew what this was.

This sounds terrible. It automatically eliminates the most common, tried and tested game texturing workflows for non-hero/unique assets and environments.

Great, thanks. I’ll explore those add-ons. :+1:

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Since you have experience… i actually have seen the smart unwrap is okay enough for me.

But i have a different question.

In the steam link you sent [i already read it before], there is this Thing about scale settings

Like how to place it 8x8 grid spaceing and other stuffs. I dont know how to do it. Can you help?

Plus my model’s Exact Dimensions are 120m by 60 m by 23m. I already made the model min those dimensions. After the correct 8x8 spacing, should i keep this same size or change them?

I don’t think I am understanding your question fully, but if you already have the model as a 1:1 scale (which I think you have with the exact dimensions you gave) where 1m of the model would be 1m in the game, then you are fine to export it as that size, no scaling required. With Blender, having the units to be 1m as they are default when set to metric is exactly what is needed for the correct size export.

The 8x8m grid is just for the game’s tiles and not really anything else, although coming from the tiles are the maximum dimensions for a model, stated here:
https://skylines.paradoxwikis.com/Asset_Editor#Buildings

Max sizes for manually placed buildings: 16x8, 15x9, 14x11, 13x12, 12x13, 11x14, 9x15 or 8x16 cells.

(Your building is within the limits.)

alright.

thanks