ZBrush UV/Tiling/Smooth UV problem

bitsy.pixel

Hello,
I'm facing a severe problem that is crippling my production work. I've been trying to solve the problem since morning.


I'm using a simple plane from maya. Default UVs. Trying to make tilable texture and displacement maps.


Export options for obj


Import to Zbrush. Save MT at lowest level. Divde. Sculpt with Wrap mode set to 1. SmoothUV off during workflow.


Normal maps extracted WITH SmoothUV on. Notice that the map isn't taking up the whole first quadrant. There is a border around it! UV border map is set to 0 pixels.


Now, the same object, WITHOUT SmoothUV. There is no map at all!!! This is happening on in the case of a plane. If I shrink the UVs a little, then tiling doesn't happen properly.

Wrap mode doesn't work! It's always off by several pixels! Texture as well as normal map! What should I do? Please help!:(

Ktonne

you'd probably be better off using projection master
here's a tutorial that shows this principle in some detail along with map extraction and end results and stuff: http://eat3d.com/free/zbrush_tile

bitsy.pixel

I've tried the tutorial. Doesn't help. Used projection master, no effect.

Internet Friend

When you subdivide your plane turn off Smoothing the "Smt" button next to Divide. You can also crease the edges of your plane, the default Plane3D in does this, but the corners will still round off a little. Either way it prevents the open edges from shrinking in size as you subdivide it.

cryrid

When your UVs aren't smoothed, they are touching the 0:1 UV borders. This causes zbrush to think they might belong to a different texture, which results in blank maps. Scale your UVs in slightly to leave some padding around the edges, and you wont have this issue.

If you do need your UVs to go to the edges of a plane to be seamless, consider using the normal matcap, or alter how you have your UV/s set up (perhaps if you wanted a 1024 map, have the UV island set to be 1024x1024 pixels inside of a larger texture, so it's just a simple photoshop crop away (perhaps even an action)

ZacD

More on cryrid's suggestion, I'd set up a grid in photoshop and Maya for the UV's that match up, and just make sure you are rendering at a higher resolution than the target (2k if its going to be 1k, for example), maybe 10 divisions each for the grid, you wouldn't even have to change the grid in maya, just snap to the 1 unit from each side.

dirigible

you could simply make your document size in zbrush a square, then apply the normals matcap, and use grabdoc.

bitsy.pixel

Thank you. I've tried all these methods. Wrap mode does not give seamless output. I don't know how to fix that. So, at the moment, I painting everything manually by hand.
Thank you very much again for all the answers