What does Roblox use to determine the UV coordinates/mapping/tiling of a Material?

Parts with Materials have a specific sort of UV Coordinate - Take a part set to wooden planks and copy/paste them, and you’ll see how each new copy has an entirely different positioning of the texture.

This is great for variety, but actually pretty bad if you’re trying to use multiple parts side-by-side and want a seamless result.

What, exactly, is Roblox using to determine how the texture is positioned? Is it completely random, or controllable somehow?

I wanted to make a wallpaper using the new Material system so I could have a sort of dynamic wallpaper texture, but naturally It’s hard to make say, individual walls, line up with the UV coordinates/tiling of the parts beside it. I suppose I could use Texture objects, but it’s a bit tedious when Materials are now so customizable.

To me it feels weird this isn’t something I can just change. Source’s Hammer toolset for instance lets you manually set the UV coordinates, and that’s old-beans technology - Not flashy fancy modern Roblox.