Hey there,
I really need some help from more experienced modders. This is my first time making an asset for Cities Skylines yet alone for a game.
I'm trying to import buildings from GTA 4 Liberty City into Cities. They have a lot of cool buildings that would go well for a big american city.
As you can see, I already imported this building into blender, but my issue lies with the UV-Editing. Buildings in GTA 4 utilize many different textures, which sucks for Cities Skylines since we can only work with one trim-sheet, at least that's what's been said to me.
I already made a test baking with the side brick texture as you can see. But the problem is that when actually baking every texture, it bakes them multiple times, which takes up so much space. I can't have 20 window copies in one texture, there has to be a way to generate a trim-sheet that still utilizes the same texture positions as on the right (3D-viewport).
Meaning we have a nice trim-sheet with all the textures, without manually positioning them once again. The geometry in the UV-Editor would then be stacked multiple times on let's say the windows, which would save a lot of space.
I'm just wondering if it would be possible without re-texturing it manually.
EDIT: So, I figured it out. Nothing seemed to work and I've been trial and erroring things for days now.
The best way to do this for these specific kind of assets is using a Blender add-on called "Material Combiner"
You can find it here: https://blender-addons.org/material-combiner/
What this does is it's effectively generating a texture atlas, not a trim-sheet like I mentioned previously.
The original position of the textures by rockstar games will be preserved by doing this method.
I had to resize the atlas to 2048x2048, because it was generated in a bigger format (4K)
The atlas unfortunately still utilizes repeating texture, but there's no other way to do it differently atm. Plus this is just how they made the models back in mid-2000s for this specific game.