BUG with Zbrush UV map [Answered]

[system]

Why Zbrush doesn’t accepts Maps inside the range from (0,0) (1,1)?. (I’m talking about texture space).

I understand this is a standard.

Zbrush works well when we have the Uv’s inside ranges from (0.0…1, 0.0…1) to (0.9999, 0.9999).

For example, if we export a PolySphere from Maya, import in Zbrush, Go to UvMap (in the Tool palette) and press “Morph Uv”, you can observe how the map is wrong.

Go to Maya, pick up all uvs, scale down it a little bit, re-export and retry Morph Uv. Now is just perfect. And all maps created from Zbrush will work perfectly.

Please, tell me this is a bug and is not intended.

Take a look at UvMap code. Someone has written a range of >0 and <1 in place of >=0 and <= 1.

[marcus_civis]

Why Zbrush doesn’t accepts Maps inside the range from (0,0) (1,1)?. (I’m talking about texture space).

I understand this is a standard.

Zbrush works well when we have the Uv’s inside ranges from (0.0…1, 0.0…1) to (0.9999, 0.9999).

For example, if we export a PolySphere from Maya, import in Zbrush, Go to UvMap (in the Tool palette) and press “Morph Uv”, you can observe how the map is wrong.

Go to Maya, pick up all uvs, scale down it a little bit, re-export and retry Morph Uv. Now is just perfect. And all maps created from Zbrush will work perfectly.

Please, tell me this is a bug and is not intended.

Take a look at UvMap code. Someone has written a range of >0 and <1 in place of >=0 and <= 1.

It’s a question of UV tile space. ZBrush can handle UV tiles but it cannot display more than one texture map at a time. If you have a UV coordinate on the border of a tile (such as 0,1) which UV tile does it belong to? ZBrush solves this by not allowing coordinates on the borders. This may not be the best solution for all situations but there is a good reason for it; it’s not a bug.

[system]

Hi Marcus. Glad to know this is not a bug.

But let me say this is a problem if you don’t know it. People uses a lot of models with uvs at range (0,0) (1,1) and it could became a true headache.

I’m nobody for request nothing, more with your update prices policy ;).

But really, if its possible, would be great that Zbrush detects if a uv have any coordinate in (0,x) (y,y), (x,0) (y,y), (x,x) (0,y), (x,x) (y,0), and ask to the user if he/she wants scale down a little bit automatically.

I’ve been getting me crazy trying to get some maps. And the majority of your users will use Uv Maps assuming this settings as a valid standard.

I hope not disturb you in any way, it is not my intention, I see your point about multi uvs maps, but I think its important warn this to the user. I swear you I’ve been getting me crazy over three days. Specially when someone do a quick test using simple geometries, which uvs often coincide with UvMap limits.

Even your own “3d Plane” of Zbrush fails. Try it, take it, make 3d mesh, subdivide, sculpt it and go to lower resolution for make a normal map. The result fails, because the Uv map of Zbrush 3d Plane goes from (0,0) to (0.97, 0.03), touching the “prohibited cords”.

Marcus, doesn’t happen anything, if it is not a bug, just a way to do things, its well, its your soft (a really really excellent one), but, well, maybe a warn about would be perfect, one of those that offers you the “skip till next restart”. Seriusly, could be a problem and with know it is more than enough.

Thank your for develop Zbrush!!.

[system]

Mudbox has what I think is a similar issue. When it detects it, it gives you a warning that you have UV’s touching the border. in general I don’t thin it is a good idea to have UVs that touch the border and when I am mapping I never do that. I always give myself room on the edges. This helps when painting in photoshop for example. The space you save by touching borders is not worth the potential headaches.

So in general when doing UVs. Don’t have them touching the boarder. If you get models that do this, request that the modeler/texture mapper change the way he/she does them. If for no other reason it causes problems with the 2 premier sculpting apps - Zbrush and Mudbox.

[zber2]

Mudbox has what I think is a similar issue. When it detects it, it gives you a warning that you have UV’s touching the border. in general I don’t thin it is a good idea to have UVs that touch the border and when I am mapping I never do that. I always give myself room on the edges. This helps when painting in photoshop for example. The space you save by touching borders is not worth the potential headaches.

So in general when doing UVs. Don’t have them touching the boarder. If you get models that do this, request that the modeler/texture mapper change the way he/she does them. If for no other reason it causes problems with the 2 premier sculpting apps - Zbrush and Mudbox.

^This

[system]

Yes, but when you’re looking for the root of a problem or do a simple test, is really easy use a simple plane as lowpoly with the default Uv Map on it.

I’m agree, and my uvMap script always leave space for extend pixels in the broders, but although is not the best idea, it continues being standard. Nevermind, with know it, its enough.

I haven’t seen any warning in Mudbox, just do the textures, at least, 2013 version.

[system]

Yeah, there should be a warning.

And also yes. Uniformly when you have default UVs created they always touch the boarder. Pretty much any app I have ever used does that. But since when do we get what we want or need from such computer generated presets? I mean usually never. In this case, it is something you learn. You make the default UV and scale it in. Simple.

As for Mudbox, yes it is there in 2013. If you try and import a mesh it will pop up. You can however turn off this waring in prefs. So maybe you can check that.

You will find it under Windows/Preferences/Files:

Validate meshes on import
When on, Mudbox automatically scans every FBX or OBJ mesh that you import to alert you to any potential problems before you spend time painting or sculpting. When off, imported files are not scanned. You can also select Mesh > Validate Meshes from the main menu bar at any time to scan all meshes in the scene.

I think it is a very reasonable request for Zbrush to have such a warning. But it should be optional.

[Cryrid]

If you do happen to be using a plane, a benefit to zbrush is that it’s document is essentially a plane itself. Just resize it to whatever resolution you want for a texture (512x512, 1024x1024, etc), frame your planar mesh, and then export the document when you’re done sculpting and painting. Instant planar texture.

[marcus_civis]

All you need to do is check the UVs by doing a Tool>Texture Map>New From UV Check. Any errors will show up red.

To scale UVs within ZBrush pick up this little plugin of mine which includes a Scale UVs button :Pixols to 3D

[system]

Thank you for the point Marcus, and thank you for the Mudbox path, Richard. I downloaded the demo for do test and try to find where was the problem.

Marcus, I would like make you a request. Would be possible you provide us the Vector Displacement diagnose test Zbrush do pushing the button “Create Diagnostic Files”, in the Vector Displacement Map section of the tool palette?.

The problem is that the .obj (the plane with the speheres) haves a UvMap that touch the borders (up & left) for the plane (the spheres are near, but any one touchs it), so Zbrush is creating wrong Vector Displacement Map (or at least, it doesn’t works for me neither in Vray for Maya nor Maxwell Render), and I’d bet is for this reason.

I don’t do myself because I haven’t the “high-resh” version of the .obj (with rounded spheres).

Ah!, In Tanget and World spaces. Tell us if uvSUV or vdSNormals are activated for the maps!.

How you can see, its not difficult forget this particularity of Zbrush, if you re-import the generated diagnose .obj in Zbrush and test it with TextureMap> New from Uv Check, you can see the errors. Nevermind, but… let’s do the round spheres diagnose works in Vray and Maxwell and a lot of vector displacements capable render engines!