ZBrushCentral

No Mtl or BMP export on object.

ZBrush Usage Questions
#1

Hi
ZB4R6
For a number of ztools no material or bmp files are being exported, and for some there are. The texture info is polypaint and it makes no difference if there are uvs on the tools or not. I redid one mesh as a test being careful to ensure it is watertight and non corrupted still no joy. Any advice appreciated.

Cheers

Edit forgot to add that colorize is on for all subtools.
Just did a test and imported the troublesome tool as a fresh obj (with reset xform) into a fresh scene via goz, painted it and exported it. The export dialog says that polypait is being writen but still no mtl or bmp file appears in the directory. I did a search on my hard drive and found a material file for the ztool with a 9 behind the name. The location of the file was c:\Users|Public\Pixologic\GoZProjects\Default. Placing the file and renaming it to fit the tool (sans 9 end) reveals the subtool wont bake diffuse in xnormal. Also creating GUV tiles and exporting the texture wont bake.

Edit: Ok I deleated the symetrical parts of one tool and it worked, I got a mtl file that baked. Other tool not so much with the same process.

Edit: Ok tried to zremesh a duplicated version of the tool (damn that is a great feature) with a new name and export the perfect projection. The shape gets exported fine and the dialog says writing polypaint data however still no cigar, no material is exported. Going to try manual retopo.

#2

ZBrush will only export a BMP file with an OBJ if there is a map applied to the model in the Tool>Texture Map sub-palette. Polypaint is not related to UVs or Texture Maps and is not supported by the OBJ format. You would need to use the ‘New from Polypaint’ button in the Texture Map sub-palette to create a map before exporting.

ZBrush doesn’t use the MTL file (other than when the materials to groups import option is on in Preferences) and if it exports the MTL file it will only have default values. ZBrush materials are only relevant in ZBrush and are not exported.

#3

Thanks marcus.
Whether the mtl file is used or not the subtools with that file bake diffuse maps (also these tools have no uvs) the subtools without that file dont bake. Also copies (with new geometry and projected detail along with diffuse) of those tools wont bake diffuse either. Weird. Going to try uv mastering the sucker. I am missing something simple I am sure of it.

#4

Kanga,

Apologies, I gave you some wrong information - ZBrush will write polypaint data to the OBJ file but it is a special tag that only a few other programs can read. XNormal can read the data. Also:

  • the MTL is only created if the model has UVs.
  • the MTL file will have a reference to a BMP file but that file will only be created if there’s a map applied (and turned on) in the Tool>Texture Map sub-palette.

I don’t have any knowledge of XNormal so can’t give you any help with that.

HTH,

#5

Thanks Marcus.
The piece is part of a 41 meter high temple so maybe that is part of it. Will put the solution here when I find it.

Cheers

#6

In xNormal, under ‘Baking Options’, I believe it is ‘Bake highpoly’s vertex colors’ option.

#7

Thanks zber2
Those boxes are unchecked. xnormal sees the diffuse from all othe subtools fine, just not the one where the ,mtl file is not created (or bmp).

Cheerio