Hello!
I just have a quick question regarding a problem when I import an object from Blender into ZBrush. When I import the obj into ZBrush, it no longer has UVs. I’m not sure if there is a special way to import that retains UVs or if I’m using the wrong method.
Thank you for your time!
Hello @RoyalSkies ,
Have you gone into Tool> UV Map and verified that the “Delete UV” button is not active? If the mesh comes into the program without an applied texture, it may be that you simply need to import and apply the texture image.
If the Delete UV button is not active then the most likely explanation is that either the export process in your external program is not exporting them, or that the geometry or UVs are problematic in some way. Please remember that ZBrush does not support overlapping UVs or multiple UV spaces. If the geometry has some sort of integrity issue, it’s possible that the UVs may not work in the program.
Does the mesh result in any warning messages when you try to import it? Once imported does it report any issues with Tool> Geometry> mesh Integrity> Check mesh?
There may also be an issue with your import procedure. Make sure to select the default polymesh3d star from the Tool menu as an import target before importing any mesh. If you import with another tool active the program thinks you want to update that mesh, and you could be encountering a scenario that is breaking your UVs.
Aside from this there’s not much I can tell you without examining the file. Please contact ZBrush Support for further assistance.
Thank you!
Hi Spyndel,
Thank you for taking the time to think about possible solutions. I’m still fairly new to ZBrush, so these explanations really help. To answer your question, the Delete UV button is active, but when I go to UV Master, I cannot flatten the UVs. And if I cannot flatten the UV’s, it doesn’t seem like I can use the multimap exporter.
I’ve noticed when I combine or ‘merge down’ objects, I often lose the UV’s in the process. Is there a solution for this?
Thank you for your time!
If “Delete UV” is active, it means there are some sort of UVs for the mesh. You could try creating a texture from polypaint and see how the polypaint displays on the mesh once converted to a texture. If it looks ok when “Create Texture from polypaint” is pressed they are probably ok. If the colors look scrambled when you convert them to a texture then there is probably an issue. That process can be found here.
There are a number of normal reasons why the UVs may not flatten. For instance if your mesh has subdivision levels it is necessary to “work on clone”. A mesh with subdivision levels cannot be flattened.
UVs are dependent on topology, and ZBrush does not support overlapping UVs. UV space is per subtool. If you change topology of a subtool you will break UVs. If the merge will result in overlapping UV islands you will also break the UVs.
For these and other reasons it is recommended not to work with UVs at all until your topology is finished and stable. This gives you much more freedom and flexibility to do what you want to the mesh, while eliminating the potential for UV related problems as well as the performance issues associated with carrying around UVs for a high resolution mesh.
I see, Thank you for taking the time to answer my question. I believe I understand what is going on now. I’ll be sure to finish my topology before adjusting UV’s.
Hope you have a wonderful day!