Make an object UV scale match another's in Maya

smous

Hello, i got a situation with UV scaling.
I know the title can be quite confusing so i'll elaborate here:

I have a road that is a width of 150 cm. And i need to apply a texture with 50 cm tiles. So in a perfect world, exactly 3 tiles should appear on my mesh.
To do so, i have unwrap a cube, and set the UV scale of one of its face to 0.05 on my UV grid. My company workflow is to say that 0.05 unit on the UV grid is equal to a meter. We make our texture on a scale of 1 square meter and we then scale the texture in 20x20 to have our ratio.
Dunno if it's the best way at all, but it's how we work here.

Then i try to match my checker with the cube's one to have the same ratio.
The thing is, it's not very accurate doing it by hand. And here i need to do it perfectly.

That being said, the question is : How can i set a mesh UV scale to match another mesh scale, in a very accurate way, automatically or manually.

Hope i was explicite enough x)

Thanks in advance for you help!

seb3d

use i.e. nightshade uv editor or maya 2017 update 3 (where they started to integrate nsuv). there you can apply an exact texel density to objects or read the density of one and apply it to others.

smous

Thanks, i recently came back to 2016 because i had problems on 2017, but i'll give it a try. Found a technique: I snap my uv island pivot on the corner of my reference cube and there i can scale much more precisely. Still kinda unaccurate, but good enough here