Strange artifacts when trying to use .exr vector displacement map

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Rowquino
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Strange artifacts when trying to use .exr vector displacement map

Post by Rowquino »

Hi,

When I try to use an .exr vector displacement map in Luxcore with an imported alembic file, I get a semi-transparent mess with lots of strange artifacts, but it works perfectly fine with Cycles. What could the issue be? I've attached links to both the Cycles and Luxcore scenes, I couldn't attach them directly because they're too large. Thanks for your help!

Rowan

https://drive.google.com/file/d/1BrgGQ_ ... sp=sharing

https://drive.google.com/file/d/1qLuJJ7 ... sp=sharing
Attachments
Cycles.JPG
Luxcore.JPG
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Dade
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Re: Strange artifacts when trying to use .exr vector displacement map

Post by Dade »

Rowquino wrote: Fri Oct 22, 2021 4:50 pm When I try to use an .exr vector displacement map in Luxcore with an imported alembic file, I get a semi-transparent mess with lots of strange artifacts, but it works perfectly fine with Cycles. What could the issue be? I've attached links to both the Cycles and Luxcore scenes, I couldn't attach them directly because they're too large. Thanks for your help!
From what I can see, your scene is working fine here:

disp.jpg

What LuxCore version are you using ?
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Rowquino
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Re: Strange artifacts when trying to use .exr vector displacement map

Post by Rowquino »

I'm using version 2.6. There aren't any artifacts in your scene but there's no vector displacement either, it's just completely flat. In the Cycles scene I screenshoted the vector displacement has been correctly applied to the rectangular portion of the geometry.
Rowquino
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Re: Strange artifacts when trying to use .exr vector displacement map

Post by Rowquino »

My mistake, I didn't include the vector displacement map, I have now uploaded this too so the scene can be properly tested:

https://drive.google.com/file/d/1PQ4K7e ... sp=sharing

Thanks again
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Dade
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Re: Strange artifacts when trying to use .exr vector displacement map

Post by Dade »

Still same result, there may be more stuff missing:

Code: Select all

Read blend: /home/david/tmp/vecdisp/Guided Ocean Layer Displacement Test Luxcore.blend
Could not open as Ogawa file from provided streams.
Unable to open /home/david/Guided_Ocean_Blender_50_UV.abc
Could not open as Ogawa file from provided streams.
Unable to open /d/Houdini Practice/Ocean_Test_25_07.abc
ERROR (bke.modifier): source/blender/blenkernel/intern/modifier.c:457 BKE_modifier_set_error: Object: "beachtank_fluid_extended", Modifier: "MeshSequenceCache", Could not create Alembic reader for file D:/Houdini Practice/Ocean_Test_25_07.abc
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Rowquino
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Re: Strange artifacts when trying to use .exr vector displacement map

Post by Rowquino »

I've applied the mesh sequence cache modifier so it shouldn't be reading any external geometries now. Here's the updated link:

https://drive.google.com/file/d/1qLuJJ7 ... sp=sharing

Thank you for your patience! :D
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Dade
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Re: Strange artifacts when trying to use .exr vector displacement map

Post by Dade »

Rowquino wrote: Wed Oct 27, 2021 4:49 pm I've applied the mesh sequence cache modifier so it shouldn't be reading any external geometries now. Here's the updated link:

https://drive.google.com/file/d/1qLuJJ7 ... sp=sharing
Nope, you are still not including the required stuff:

Code: Select all

Unable to open /home/david/Guided_Ocean_Blender_50_UV.abc
[...]
WARNING: Node "Imagemap" in tree "Beach Tank Ocean Spectrum": Could not find image "ocean_displace.layer_0.25_07.1.exr" at path "D:/Houdini Practice/maps/ocean_displace.layer_0.25_07.1.exr" (Not an existing file: "D:/Houdini Practice/maps/ocean_displace.layer_0.25_07.1.exr")
Try to create a new scene from scratch and include any file you are referencing :idea:
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Rowquino
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Re: Strange artifacts when trying to use .exr vector displacement map

Post by Rowquino »

Okay so I've remade the file as just the one mesh and the displacement map, which I have packed into the blend file. I've also tested copying the blend file onto different parts of my computer and the displacement map is always recognised so the packing does seem to have worked. Here's the link:

https://drive.google.com/file/d/1qLuJJ7 ... sp=sharing
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Dade
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Re: Strange artifacts when trying to use .exr vector displacement map

Post by Dade »

Rowquino wrote: Tue Nov 02, 2021 8:54 am Okay so I've remade the file as just the one mesh and the displacement map, which I have packed into the blend file. I've also tested copying the blend file onto different parts of my computer and the displacement map is always recognised so the packing does seem to have worked. Here's the link:

https://drive.google.com/file/d/1qLuJJ7 ... sp=sharing
You are setting the displacement map image gamma to 2.2: the reverse gamma correction (i.e. raw rendering is done linear color space without gamma correction) will destroy the values of the image pixels.

Check the image map flag "Normal map" to avoid any reverse gamma correction. You can than increase the displacement scale to see the map applied.

It should be all (not sure how exactly the rendering is supposed to look).
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Rowquino
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Re: Strange artifacts when trying to use .exr vector displacement map

Post by Rowquino »

Dade wrote: Tue Nov 02, 2021 9:25 am
Rowquino wrote: Tue Nov 02, 2021 8:54 am Okay so I've remade the file as just the one mesh and the displacement map, which I have packed into the blend file. I've also tested copying the blend file onto different parts of my computer and the displacement map is always recognised so the packing does seem to have worked. Here's the link:

https://drive.google.com/file/d/1qLuJJ7 ... sp=sharing
You are setting the displacement map image gamma to 2.2: the reverse gamma correction (i.e. raw rendering is done linear color space without gamma correction) will destroy the values of the image pixels.

Check the image map flag "Normal map" to avoid any reverse gamma correction. You can than increase the displacement scale to see the map applied.

It should be all (not sure how exactly the rendering is supposed to look).
When I check 'Normal map', the Vector socket of the Vector Displacement node shows 'Wrong Input!' and however high I set the displacement, nothing shows in the render. The rendering is supposed to look like the image I posted at the top of the thread:
Attachments
Cycles.JPG
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