My Workflow (And Why It Fails)

ralusek

So I either start with maya basemesh and take it to zbrush, or i just start going at a zsketch model until I get what I want.

I sculpt it, I retopo it in zbrush, and then I project it. Here is the problem though. Projecting seems to function as bad, if not worse, than ever. and I constantly have to smooth, reproject, go in with the zproject brush, etc...and i still encounter weird artifacts all the time. This is where I would grab my normal map from...being the new model with projected detail.

Now, as I understand it, a lot of people just sculpt a model, make a game model on top of it, and just grab normal map FROM their original sculpt. in other words, there is no projection. that seems like you would potentially run into less problems, however, i don't understand how you would get your UV's to match up. I mean even if you mapped the game model to roughly fit the sculpts UV's, you'd definitely run into different seams and problems...and you also have to UV twice. (and you could never UV map a unified mesh that came from a zsketch)

so if someone could clarify, or just reassure me that projecting is something i'm going to have to work with every time, i'd really appreciate it.

MoP

The part where you talk about "making the game model UVs match the sculpt UVs" is where my mind starts boggling...

You have never needed to do this, your sculpt doesn't need to have UVs at all. What made you think this was necessary?

garriola83

yes you can retopo in zbrush but there are programs like topogun that can retopo for you. i on the otherhand use 3dsmax graphite modeling tools to retopo. you can bring in a fairly subdivided mesh into maya and retopo from there. and of course unwrap. then when your ready bring in a fairly detailed sculpt, optimize it, then bake the normals.

i dunno how other ppl do it but thats the workflow from the GoW guys so i'll take their work on it.

cryrid

The only time you should have to UV the highpoly model is if you wish to transfer the polypainting to the new game-ready mesh you created outside of zbrush. But even then Auto-UVs and the baking process itself take care of things so you dont have to worry about different UV seams.

See http://eat3d.com/free_zbrush_xnormal_pipe for the tutorial on this.

Ark

Uving the highpoly meshes can sometimes be useful for applying bumps to the highpoly to transfer, but you can do this in photoshop later anyways.

Just a word on Uv's on really high density meshes increase there filesizes dramatically and have caused issues for me before. I always delete them when not using them.

ralusek

i was referring to uving the high poly because i was speaking only of zbrush. but upon looking at xnormal again, it looks like you just put the detail from the high poly using the low poly's uvws, is that right?

Avanthera

well, yes.
you dont even need to use the same uvs in zbrush. or when you are using polypaint.
if you have the low poly with uvs, you can bake down the high polys details and texture, even if the high has screwed uvs (like auv or guv in zbrush).

if you just need normal maps, there is no reason to even have uvs on your high poly. ever.
xnormal and all other normal map baking software (xept' zbrush, silo, and mudbox) use a cage to physically shoot rays through the high mesh to the low mesh, then to the corresponding bit in the uv set.

in the three exceptions programs, they use a difference analyzer between the low poly mesh and the subdivided and detailed version of that same mesh. (hence why you have to project your details from your sculpture to your uv'd and subdivided low poly in zbrush.)
either way is good, just depends on which way is faster for you.:)

These two are the best resources for normal mapping ever, they explain it better than I can.
http://www.bencloward.com/tutorials_normal_maps1.shtml
http://paultosca.com/makingofvarga.html

Ben Apuna

Yup that's right, there's no need for UVs on the high poly with xNormal. The detail is captured through raycast methods rather than matching UVs.

As a side note I have used the matching UV method once or twice in the past with really crazy organic shapes that made cage and raycast methods of baking very troublesome to work with. UV matching seemed to churn out bake error free maps (no inverted colors and no intersections), though it was a pita to keep the high poly's UVs matching the low poly.