Zbrush Basic Questions

Aured

Hello all. I'm getting started with the very basics of Zbrush, and, while I've learned a lot about brushes, alphas and masking, I'm a little unsure about how to do a few other things. 

Firstly, importing my own meshes. Zbrush features a click and drag system, which works fine but I'm not sure if this is messing up the scale of my object or not. I'm worried that when I am done sculpting and I export it, the size of the mesh will not match the size it was originally. Can somebody clarify this?  

Secondly, the mesh I want to import is divided up into several different objects to make it easier to sculpt certain parts. I'd like to import these as subtools but I a) don't know how to import them as subtools at all and b) don't know how to get them to remain in the same position and at the same scale as they have been exported from Maya.  

Can anybody help with this? Thank you in advance. 

Magihat

Aured said:

Can somebody clarify this?  

It won't change the scale when you reimport it.

Aured said:

Secondly, the mesh I want to import is divided up into several different objects to make it easier to sculpt certain parts. I'd like to import these as subtools but I a) don't know how to import them as subtools at all and b) don't know how to get them to remain in the same position and at the same scale as they have been exported from Maya.  

Export them as separate objects in Maya, import into zbrush (remember to select a default subtool like the star or a sphere each time you import so that you don't overwrite the one you imported previously) and then use append to attach them to the same subtool and they will retain their position.

Aured

That was quick! Thank you. 

cryrid

I use Subtool Master's Multi Append  to import my files. This works for both single files and importing multiple objects at once, and it preserves the scale and position when going between my programs. 

Aured

Right, back again. Everything worked just fine, but now I've run into another couple of things I don't know how to do.

I've sculpted the model to be how I want it, and I've applied noise maker to just about the entire model. What I'm trying to do is merge the subtools together to make one single mesh for normal map baking in xNormal. The problem is that when I merge the model together, the noise maker deformation is completely erased and I am left with just a smoothed out model. Do you know what's going wrong with it?  

Bek

You need to "apply" the noise to the mesh, simply having it active is like a preview only. However, once you apply the noise you will probably notice a new problem — the noise made a mess of your mesh or just looks odd. You need pretty high resolution geometry for the noise to work well, and if it's being applied at a high strength it might be intense enough to poke holes everywhere.

Also, why do you want to combine the meshes to bake? Keeping them separate should keep things simpler; unless you need to actually dynamesh geometry together or something.

Aured

Hello Bek. I am currently working with about 13 million polygons. Is that high enough resolution? When I apply the noise, the resulting deformation is of significantly lower quality than the preview. I need to find a way to fix this, because I have the mesh exactly how I want it with the preview.

I want to combine the meshes to bake because the final, game-ready mesh will consist of all these meshes and share a single normal map. I suppose I could bake each texture onto the original mesh it came from and then combine them in Photoshop, but I'd prefer to just get the normal texture out in a single bake from high-poly to low-poly. The only thing that is stopping me from doing this is the fact that I can't get the meshes to combine with the noise properly applied.    

Bek

You don't need to merge the highpolies in that case, you can simply load multiple highpoly pieces into xNormal and bake them to the one lowpoly mesh (thus skipping the need to manually piece together several different textures in photoshop). As for the noise, trial and error I think. If your preview has detail smaller than your meshes polygons, it's obviously not going to show up. So you'll need to either subdivided your mesh and try again, or perhaps consider adding the noise another way (tiling texture overlayed in photoshop, or projected onto the lowpoly in some seamless way like in substance painter/designer).

Aured

I subdivided the model again, and the noise applies perfectly now. Not only that, but exporting the .obj and baking the normal map on xNormal works fine as well. I have some normal map errors, but I should be able to solve that issue on my own. Thanks for helping a noob out, and I'll post if anything else comes up.