is this a displacement bug?

Foundry Modo (Developed by stenson, Integrated Plugin developed by Paul Kinnane)

Moderator: face_off

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portnicki
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Hey,

I'm using a displacement map on a flat surface to make small letter-shaped indentation. It needs to be really subtle (almos bump-like, but there will be close ups so I'd rather use displacement).

The problem is, the lower the dislpacement value, the more strange artifacts I get.
Check it out:

Image

what's wrong here?
i7 2600k + nVidia TITAN black
https://www.behance.net/Auror
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face_off
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As the displacement amount gets smaller, the polygons being displaced need to be smaller, otherwise you get artifacts. So if you subd the mesh it should fix the problem. See point 4) in the Displacement section of the Octane Notes in my signature.

Paul
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Octane Plugin Support : Poser, ArchiCAD, Revit, Inventor, AutoCAD, Rhino, Modo, Nuke
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portnicki
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face_off wrote:As the displacement amount gets smaller, the polygons being displaced need to be smaller, otherwise you get artifacts. So if you subd the mesh it should fix the problem. See point 4) in the Displacement section of the Octane Notes in my signature.

Paul
Paul are you sure this is the case?

I've subdivided my mesh from 2570 polys on subdivision level 2, to 40.000+ polys on subdivision level 3 and this is the effect:
Image

the render errors are still there, just smaller
i7 2600k + nVidia TITAN black
https://www.behance.net/Auror
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face_off
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It would be worth lowering the ray epsilon - just in case those artifacts are self-shadowing. If that does not help - can you package a sample up in ORBX format and send to me and I'll send it to the Octane devs.

Paul
Win7/Win10/Mavericks/Mint 17 - GTX550Ti/GT640M
Octane Plugin Support : Poser, ArchiCAD, Revit, Inventor, AutoCAD, Rhino, Modo, Nuke
Pls read before submitting a support question
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face_off
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The other options are to a) use that texturemap as bump instead of displacement, and b) scale the scene up x10 (or x100) which will most probably resolve the issue (since then the "Amount" could also be increased).

Paul
Win7/Win10/Mavericks/Mint 17 - GTX550Ti/GT640M
Octane Plugin Support : Poser, ArchiCAD, Revit, Inventor, AutoCAD, Rhino, Modo, Nuke
Pls read before submitting a support question
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