Help with unwrap and textel density for modular tilable environment

Asim7

Hi there

Im trying to make a small modular environment for UE4, with handpainted textures.

I however just can't wrap my head around, how to unwrap these models with proper unwraps, textel density and still being able to tile them.

I have linked a imgur album of my modular pieces and some of the unwraps, so i don't fill this post up with images.

Imgur link: https://imgur.com/a/MzWGe

Also, should i make each object have it's own texture, or should i combine it all into a larger texture atlas? I'v heard UE4 dosn't really use texture atlas with modular pieces.

I'v had a look at some tutorials, but none of those i was able to find went over this part in detail.

Any help would be very appreciated, as i really have no idea how to continue with this. 

Larry

I am only starting out as well but I think if u want these walls to be seamless togetger, their uv"s have to extend to all of the 0-1 uv space, from left to right. You can put all of the pieces in 1 channel and overlapping. Unless your material will be a simple color and noise, then you dont have to do the above.Have you created a second uv channel for lightmaps? 

Also a heads up, if you place these assets in the engine the way they are, you will get lighting seams between them and there is no workaround to remove them cometely. So you either have to place a column where the seam is, or block a whole room as a single piece, or make your material having a straight line on where the seam is, e.g. like between the bricks, to hide it

Asim7

Good point with the lighting seams between them, I didn't really know how that worked. Sometimes they'd show up but other times they didn't. But yes you're right, i plan on putting some columns in between.

My original plan was to use a 4k texture atlas, and unwrap all the modular pieces into it. I created it all with power of two, so my texture in the atlas would be the same. For example a 256cm x 256cm wall would have 256px x 256px in the atlas. And i was thinking if i duplicated the textures across the atlas, i could make the models tile from side to side. It might not have been the best idea, especially if UE4 dosn't really work like that. Which would mean each model would use a 4k texture for no reason.

Your saying i should just unwrap them all to fill a entire uv space, without thinking of overlapping? Because all the light bakes and such will be in the second UV channel?

Thanks a lot for responding btw, any help is appreciated

Larry

You could do that ..In UE4 using 1 texture of 4k is better than using 4 textures of 1k. And that is related to draw calls. The more UE4 has to draw from a library, the less the performance. That is what i figured from videos and i don't know if it is correct.Also if you have all pieces in 1 4k texture, that is fixed ,and you would have to rebuild your texture if you want something different. Going back and forth is more time consuming than being able to create it in real time. So if you are fine with that, proceed the way you want to

Eric Chadwick

This should help
http://wiki.polycount.com/wiki/Modular_environments

Asim7

Eric Chadwick said:

This should help
http://wiki.polycount.com/wiki/Modular_environments

Thanks, i just had a look at this one http://polycount.com/discussion/144838/ue4-modular-building-set-breakdown/p1 with seems to go over what i have trouble with, which is the UV mapping.

In one of his pictures he has a 3x2 wall, which he unwraps like this http://images.purepolygons.com/building_tut/build_tut_01.jpg

I have a similair wall, but mine is 256cmx256cm Here is my unwrap http://i.imgur.com/lWwtBuv.jpg
I don't see how i can fill the entire UV space, and still make room for the top and inside of the window.
If i make the wall smaller in the UV editor, to only fill 1/4 of the square. Won't the texture density be wrong/small? And i wouldn't be able to tile it. My texture would be 256x256px to match the wall size.

Not sure if im overcomplicating things, i just don't seem to get this part.