Efficiently Texturing for Modular Buildings?

Development Rendering
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1

So, I’ve begun modeling static mesh kits for exteriors and interiors using Blender. I basically have a firm grasp about how it works, except texturing. I’ve heard that overlapping UVs are the way to go, and for seamless results, this of course makes a lot of sense. BUT, how do I go about adding different variations in these UVs to accurately portray different material types? So, for example, let’s say I create a kit that has many different pieces, and the target materials would include concrete, metal, glass, wood and brick on a single overlapped UV map. How do I go about accurately portraying all of these materials on a single mesh that has a single UV map? Should I unwrap each piece separately in this case then? What if I have hundreds of pieces? What if I want to get very detailed? Do I have to paint each piece in substance painter? Basically, how can I have reflective glass windows, brick, metal and concrete portrayed accurately on one mesh that that has trim, windows, windowframes, etc. already built into it? That doesn’t even seem possible. A lot of the tutorials I’ve seen seem to glaze over the important texturing process and how overlapping UVs can work. They go from point A: Modeling to Point B: A realistic and beautiful building. Any special insight would be greatly appreciated!

I’m making a PC Game. Basically, how do I make the materials, lay out the model UVs and planning.

Let’s say I wanted to make a whole building like this:

Or even this:

941×1024 261 KB

And let’s even go out on a limb to say I’d be making interiors…like this:

1240×951 200 KB

And even this:

But for now - how about this:

I’m making inaccessible exteriors. Building faces complete with doorframes, doors, windows, trim, you name it all on one static mesh. How can I have different material properties on that single mesh?

Additionally, let’s say I wanted to make an interior component of many modular pieces…how can I go about effectively adding texture/materials to that?

What if I made an enterable building with exterior AND interior? One side was brick, and the other was plaster, wainscotting and trim/moulding…Mostly complex things like this.

2

PC Game. Basically, how to make the materials, lay out the model UVs and planning.

Let’s say I wanted to make a whole building like this:

Or even this:

941×1024 261 KB

And let’s even go out on a limb to say I’d be making interiors…like this:

1240×951 200 KB

And even this:

But for now - how about this:

I’m making inaccessible exteriors. Building faces complete with doorframes, doors, windows, trim, you name it all on one static mesh. How can I have different material properties on that single mesh?

Additionally, let’s say I wanted to make an interior component of many modular pieces…how can I go about effectively adding texture/materials to that?

What if I made an enterable building with exterior AND interior? One side was brick, and the other was plaster, wainscotting and trim/moulding…Mostly complex things like this.

3

to get different material properties within the same material, you just use multiple greyscale images in the material, to control things like roughness, metalness, emmissive, etc… you can pack 3 or 4 of these images into a single texture, using each RGBA channel as a separate greyscale image, and you can use multiple textures in the same material

http://wiki.polycount.com/wiki/Modular_environments

http://images.purepolygons.com/building_tut/build_tut_05.jpg

https://www.artstation.com/artwork/LmGeK

and as far as organizing the textures, that can be a tricky thing to plan out. usually, for a PC game, you have tilable textures, trim textures, prop textures, and decal textures. trim textures are like tilable textures, but they only tile in 1 direction, and they are often packed with many trims in 1 sheet. decal textures are where you put any details that need transparency, like torn cloth, light shafts, grime, etc… if you want alot of architectural variety in one area, without killing your frame rate with too many draw calls, its good to atlas many textures into one. this is very important for mobile, but it helps on PC as well.

http://www.vicbonilla.com/images/3d_images/Textures_Venice%20Atlas.jpg

when you combine a bunch of trim sheets and prop sheets like this onto a single texture, and also have a few separate tilable textures, like brick, stucco, and roof tiles, etc… you can get most objects to have 1 or 2 materials, which is good on performance.

so for your examples, i would start with the wood. make a generic tiling wood texture, so you can cover large areas like table tops, then make a separate damaged version that you can blend between with a mask. then make a tiling wood floor planks texture, then make a tiling wood trims texture. the wood trims will be where all the wainscoting panels and moldings go. then make a wood props texture, where you put the odd parts like broken pieces of wood, wood arches, keystones, clock faces, locks, door handles, etc… basically knobs and junk.

if you set up a master wood material, and material instances that swap out the texture parameters, and make that master wood material multiply its grayscale masks against the model’s vertex color, you can basically use this small set of wood textures for all of the wood in your game. on mobile, it would be a good idea to atlas all of these textures onto large sheets, packing them into 1024 or 2048 textures. but if you pack tiling trims in a way that doesn’t allow them to tile, you have to cut loops into your geometry based on where you want it to tile.

for brick trims, this is a good reference:

here’s an example of stone building facade textures:

and if you want an example of faked 3D building window material, for upper floors of buildings, you can look at the materials used here:
http://www.thiagoklafke.com/makingofsampa.html

4

there we go.

5

Ah, thanks for the resources and the explanation! Now I understand a little better. I’m really just starting out, so a lot of the node setups for materials are pretty complicated to me. With some practice as simple stuff, I should be able to get this.

6

So, based on both these answers, masks are the key. I had thought about texturing things like tables, clocks, silverware, even larger stuff like chimneys in substance painter still. Now, normal maps can be used in this masking process too I’m guessing? I’m coming straight from 1998 Goldsource right to UE4, so there’s a lot of info between now and then I have to catch up on, haha.

7

you can look up “unearthly challenge” and “Polycount Art Dump” to find tons of great references.

realistic examples:
http://erinmckown.com/material-studies.html

stylized examples:

here are some good shader masking references:
http://artisaverb.info/Desert.html