Tutorial for Sculpting on UVs in Zbrush
polycounter lvl 13
The goal of this tutorial is to show how you can quickly create & edit a normal map without baking and without having to use Photoshop filters and gradient alone (which tend to give a volume-less, procedural, flat looking normal map). Some of you may know a lot of the basic's I am covering, but advanced game developers should get some helpful info here as well!
Have any comments or questions or feedback? Just reply to this posting and I'll get back to you!
Replies
Ughhhhh. This is a cool technique but I wouldn't rely on it too much.
Please don't do this if you have time to sculpt it on an actual high resolution mesh. If you don't have time then you should punch somebody square in the dick and tell them you need more time if you want any kind of quality to the art (and normals/AO)
Need to Frankenstein the shit out of an existing texture by putting a bunch of stitches on it? This technique is probably a decent solution, especially if you're just doing overlays of small details.
Ceebee, u are absolutely right about having time to sculpt on a real mesh, but when time is an issue, which happens in tight development cycles, and your not a fan or painting normal maps from scratch, then this is a viable option.
Not to mention, you need to download a specific Material for ZB for this to be shown 'correctly'? That's kinda risky, especially on some workstations, you can get a ZB fart and get the old material loaded instead of the new one.
I mean it doesn't look faster compared to what an afternoon or two will net you, complete with cage and baking included correctly for your final renderer.
I might as well say this, use NDo2 if you're going to do something like this, you will get both a previewer with the mesh, able to generate several maps, and have access to all the information needed in real-time.
The Average character on my project takes about 12-18 days to create. Sometimes a producer will ask you to take the existing geometry and quickly do a completely new design in 3 days. This technique is mainly meant to be used in these circumstances. Of course it is not meant to replace high poly modeling at all.
As for NDO2, I have it here and I use its conversion function all the time (for cavity, AO...), but I feel the painting normals aspect to be very stiff and procedural. Again that's just IMO, I would always rather sculpt it in Zbrush, and if my time budget doesn't allow for that, then I go to this technique which uses the same tools i would use normally to get great results at a 3rd of the time.
Hope that helps clarify. And thanks again for the feedback!
on a second note, you may be able to cut out a few steps by importing your lowpoly Uv'd mesh in to Zbrush, do "groups by UV", then using UV Master to create your flat layout.
If you subdivide before flattening, you should be able to switch back and forth between flattened and unflattened to review your details and fix the seams.
edit, and thanks for sharing!
And, sometimes existing unwrapping can no match with your goals. For instance, torso is divided into two UVs with different sculp, colour etc. But, you need the sculpt to be equal across the torso, to make it kinda single part. That can be complicated, no?