Hiya,
We’ve purchased a single Zbrush license to see if we can incorporate zbrush into our art pipeline mainly for generating normal maps for realtime use.
We would also be using the displacement map generation for marketing material use to create high quality versions of the game models.
This is the approach we are planning to take.
We originate our meshes in Maya, then UV them. Now previously we went straight ahead with generating textures in photoshop, which would now be replaced by the generation of normal maps in zbrush since we can use the maps coming out of zbrush in photoshop later for the likes of specular maps etc.
Often we have the following limitations on our models:
The data we get out of Zbrush is the normal map based on local/tangent space for the obvious reasons.
The models are often symetrical and as such share half a texture on both sides. This obviously does not work for normal maps, so we’ve decided to try out for 2 choices. Firstly would be doing the normal for the same half side as the normal texture and letting our build process handle the mirrored side. The second would be to give it a seperate UV channel where there is no UV overlap-age and do a normal map for both sides of the character.
Obviously the first option has our preference since it would require no extra work, and we would end up having double the x res on the normal map.
With this I come to my first problem, which is mirroring the sculpting to the other side… this works well if the mirroring edges are all quads, but it’s something we can;t always afford. On mirroring edges with triangles coming off them especially the mirroring seems to not work properly. Is there any way to “lock” the mirroring edges so they stay where they are?
On generation of the normal map does zbrush assume the base mesh normals are all “soft”/smooth shaded or “hard”/faceted?
Because usually the base mesh used in the game will have a mixture of the 2 and will exhibit shading artifacts (ofcourse it is not a problem making them all either soft or hard but it wouldbe good to know)
Is there any way to display the mesh in zbrush as smooth shaded rather than faceted ?
The display properties in the tool menu don’t seem to do anything.
Is it possible to export the high res mesh as obj but with options for triangulation and smooth or faceted shading?
If I decided to delete one side of the mesh it also deletes the top level of smoothness on meshes with a history. Because it doesn’t seem to generate proper normal maps if the whole object is visible when using mirrored UV’s but has only one side sculpted. Altho masking out the non edited side seemed to fix this.
Would there be a way to force zbrush to duplicate/“mirror” sculpts made on overlapping/mirrored UV parts on the mesh?
Rather than basing it on a global mirror?
Say for instance you have a long tail with 8 segments and the tail pattern is repeated 4 times over that, you would only want to sculpt it once and use the same part on all other bits that share those UV’s aswell.
Not knowing what the end result would be I accidentally pressed the smootheUV button while dividing, now this has had an adverse effect on the final normal map (as it doesn’t match up with the UV map for the low res mesh at all!!). Is there a way to reverse this as it still has complete division history.
Obviously I can’t use it as is to generate a displacment map and bake that either as again, the UV’s won’t match up!
As a general comment I find the help a little inadequate in describing the actual effect it has on the workflow. But I suppose it is just part of the learning process on my side 
Any suggestions regarding workflow ar more than welcome!
Elco