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I'm trying to make a model of the moon to be 3D printed. This means that I need a real displaced mesh, and shader or material displacements wont work (sorry if the terminology is not right).

I would like to use Geometry Nodes because of its advantages. I've already did it using the old method of image texture without GN, but it presents several disadvantages, specially when you need to make changes in the final mesh.

The problem is that I get a seam where the vertical edges (left and right) of the displacement image meet. It can be seen in the uploaded image along with the Geometry Node Editor. How can this be avoided?

The UV Sphere and all other Blender parameters have its default values.

I'm using Blender 3.3 for Mac OS.

The source of the displacement image is link.

Thanks in advanced.

Moon with Geometry Nodes

Joe Ercolino
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  • The UV Sphere and all other Blender parameters have its default values. – Joe Ercolino Nov 18 '22 at 07:42
  • I've mentioned that the model will be needed for 3D printing, because I need a real displaced mesh, and shader or material displacements wont work (sorry if the terminology is not right). – Joe Ercolino Nov 19 '22 at 11:43
  • if the image isn't repeating itself in the meaning of: it looks the same at both edges....i think it is pretty impossible, because you are using an image. maybe try a procedural way? or use another image? if this isn't your problem, could you pls provide blend file? thx – Chris Nov 19 '22 at 11:50
  • @Chris thanks for your comment. The image is the all-around height field of the moon and both, right and left edges, are meant to be neighbours, so the corresponding height and grey values in both edges are similar. This means that the image can be repeated horizontally without a noticeable seam.

    As I said, I've already did it by using image texture without Geometry Nodes, but it presents several disadvantages with respect to GN, specially when you need to make changes in the final mesh.

     – Joe Ercolino Nov 19 '22 at 15:56
  • @Chris here is the file:

    link

     – Joe Ercolino Nov 19 '22 at 16:11
  • i cannot download unfortunately: [1]: https://i.stack.imgur.com/qMf6j.png it says it's harmful and google did block it – Chris Nov 19 '22 at 16:58
  • @Chris I don't know why are you getting that message. The link is

    https://filedropper.com/d/s/brWIsymG68EB0KcnC9joPKL7k9p8Ga

    I still can download it and is a zip file with the same blender file plus the moon image.

     – Joe Ercolino Nov 20 '22 at 14:26
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    FYI, I had the same problem on Chrome as well, fortunately Edge did let me download it. Maybe the MacOS-related files inside the zip tripped it up. – Kuboå Nov 20 '22 at 14:32

1 Answers1

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You're using a UVMap for your vector information source, which is in Face Corner domain. This means right at the seam, your values are doubled, because while the mesh has only one vertex there, two face corners are present—both left and right side of your image is occupying those same points. You can get rid of it by simply 'converting' between the two domains using an Interpolate Domain node:

enter image description here

Kuboå
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  • Thanks @Kuboå. Just what was needed! – Joe Ercolino Nov 19 '22 at 17:47
  • Could you upload the file in your answer as well? I wanted to try something with it, but I cannot download the original file - none of my browsers allows it and my antivirus software says it's a trojan. – Gordon Brinkmann Mar 16 '23 at 08:38
  • @GordonBrinkmann Sorry, doesn't seem to work for me anymore either. Maybe try downloading from the original NASA site, there's a link in the answer. – Kuboå Mar 16 '23 at 17:53
  • Oh, okay then. I thought you had the file since you worked on it. I was looking for the complete file, not just the NASA textures (I have loads of NASA textures). – Gordon Brinkmann Mar 16 '23 at 17:56