Checkered displacment bug

Every now and than I get this error in blender which doesn’t easily resolve itself. Basically the displacement map doesn’t work and a weird checkerboard pattern appears around detailed areas. I have everything set up properly and it has worked in the past so not sure what causes it. Any ideas? Its really ugly.

How do your UVs look?

Do you see the same problem in the rendered images or is it only in the viewport?

The problem occurs in viewport and render. I kind of think its somehow duplicate the vertices somehow from zbrush. I’m using gob. Might be some odd grouping issue. I forget how to merge duplicates. You can see how when I’m trying to select the uv island I cant simply select the whole island. And there appears to sets of vertices on the closeup.

What causes the error is a goz import with GOB from zbrush. When I just export out a obj file from zbrush it comes in without the weird render. Only thing odd is the uvs are flipped but thats easy to fix with mirroring. I still want to fix the setting that is causing it since goz is nice in terms of not having to worry about removing extra data that comes in from obj files each time I update the mesh.

It looks as if you need to remove doubles. Just press Alt+M (for merge) and select By Distance.
Hope this helps.

The remove doubles doesn’t resolve it sadly.

I think it did not solve because of the distance between the vertices is larger than the selected offset.

One thing I could see, and I can be wrong, is that not only you have duplicated vertices, but it seems like you have the whole geometry duplicated, like you have two models in one. If you have faces competing on the same positions it’s normal to have this kind of problems, specially with normal maps involved.

Its possible that in the process os modeling you have duplicated the whole mesh without being aware of.

You should get rid of one of those. Make a copy of your model and make a test.

If you look here, you can see the duplicated mesh in grey lines.

Its not that. I couldn’t reproduce that error. I tried doing several more tests from gob to blender. And the problem is the UVS themselves. They are somehow broken in the process of exporting them. There is only single vertice so no two meshes.

When I just export and obj from zbrush normally the UV island can be selected entirely with the L key. However the GOB imported meshes l only selects a small sliver of the uv mesh. Which leads me to believe their is all sorts of random cuts on the uv islands. The islands look intact so maybe blender has a way of fixing this in the UV editor?

Is there a way of stitching the islands easily as a workaround?