Luxcore really needs an anisotropic rotation option

Use this forum for general user support and related questions.
Forum rules
Please upload a testscene that allows developers to reproduce the problem, and attach some images.
Post Reply
User avatar
khaldrogo
Posts: 1
Joined: Fri Apr 16, 2021 10:13 am

Luxcore really needs an anisotropic rotation option

Post by khaldrogo »

REDACTED: This was a spam post: Post something reasonable sounding first (probably copied from elsewhere), then edit it into spam later...
Last edited by CodeHD on Mon May 12, 2025 8:01 am, edited 14 times in total.
Reason: remove spam
User avatar
Dade
Developer
Developer
Posts: 5675
Joined: Mon Dec 04, 2017 8:36 pm
Location: Italy

Re: Luxcore really needs an anisotropic rotation option

Post by Dade »

khaldrogo wrote: Fri Apr 16, 2021 10:23 am I have not seen an X/Y workflow
Actually, LuxCore uses an U/V workflow: the anisotropic follows U/V coordinates so it can be rotated by rotating the UV coordinates. However, I'm not sure to understand your topic, can you add some link about this feature ? Like how it is supported in Vray, etc. ?
Support LuxCoreRender project with salts and bounties
nostalphia
Posts: 5
Joined: Sun May 11, 2025 4:38 pm

Re: Luxcore really needs an anisotropic rotation option

Post by nostalphia »

Dade wrote: Fri Apr 16, 2021 10:35 am
khaldrogo wrote: Fri Apr 16, 2021 10:23 am I have not seen an X/Y workflow
Actually, LuxCore uses an U/V workflow: the anisotropic follows U/V coordinates so it can be rotated by rotating the UV coordinates. However, I'm not sure to understand your topic, can you add some link about this feature ? Like how it is supported in Vray, etc. ?
Greetings!
Apologies for my poor English,
I can understand that {u-rough=1&v-rough=0} can achieve a tight brushed texture sorted by left - right; and a circular or radial texture by rotating the uv,
ImageImage
(Adding subD (level 3) to the circular texture brings terrible saw aliasings)

but it becomes difficult when cannot changing the uv for some reason:
Image
in the U/V workflow, the u-rough = v-rough of Apoint and Bpoint(two points at ±45°) , who should be opposite value :o .
CodeHD
Developer
Developer
Posts: 482
Joined: Tue Dec 11, 2018 12:38 pm
Location: Germany

Re: Luxcore really needs an anisotropic rotation option

Post by CodeHD »

nostalphia wrote: Sun May 11, 2025 6:42 pm ...
(Adding subD (level 3) to the circular texture brings terrible saw aliasings)

but it becomes difficult when cannot changing the uv for some reason
in the U/V workflow, the u-rough = v-rough of Apoint and Bpoint(two points at ±45°) , who should be opposite value :o .
Hello,

Could you explain this in a little more detail, please?
For example, about the second issue, can you show a comparison of how it is supposed to look?
Ideally, always include a blend file (simple and with textures included) so that your setup can be better understood.
nostalphia
Posts: 5
Joined: Sun May 11, 2025 4:38 pm

Re: Luxcore really needs an anisotropic rotation option

Post by nostalphia »

CodeHD wrote: Mon May 12, 2025 8:35 am
nostalphia wrote: Sun May 11, 2025 6:42 pm ...
(Adding subD (level 3) to the circular texture brings terrible saw aliasings)

but it becomes difficult when cannot changing the uv for some reason
in the U/V workflow, the u-rough = v-rough of Apoint and Bpoint(two points at ±45°) , who should be opposite value :o .
Hello,

Could you explain this in a little more detail, please?
For example, about the second issue, can you show a comparison of how it is supposed to look?
Ideally, always include a blend file (simple and with textures included) so that your setup can be better understood.
Hello Hello,
When I'm dealing with some oddly shaped objects, I can't get the desired effect by changing their UVs, here's an example:
Image
Its scratches are roughly like this:
Image
This is a mechanical watch movement deck, decorated with a regular (sort of) texture called Geneva stripes,which made by countless circular scratches arranged in parallel.
When using anisotropic rotation to implement a circular texture, this can be achieved by setting anisotropy ≠ 0 and linking a conical gradient to the anisotropic rotation:
Image
(Looking from the z-axis, sun shine's highlights are generated in the area perpendicular to the scratches)
Geneva stripes,which made by countless circular scratches arranged in parallel,can be achieved in a similar way:
Image

But if in u/v roughness workflow, I find it difficult to find some intuitive way to get a physically consistent result.

p.s, I haven't found a way to upload .blend files yet, maybe I could get your email address?
-------------------------------
to
CodeHD
Developer
Developer
Posts: 482
Joined: Tue Dec 11, 2018 12:38 pm
Location: Germany

Re: Luxcore really needs an anisotropic rotation option

Post by CodeHD »

nostalphia wrote: Tue May 13, 2025 10:03 am p.s, I haven't found a way to upload .blend files yet, maybe I could get your email address?
You can attach files directly to messages in this board, including .blend files.

The same with images, you don't need to use postimages.cc!
nostalphia
Posts: 5
Joined: Sun May 11, 2025 4:38 pm

Re: Luxcore really needs an anisotropic rotation option

Post by nostalphia »

CodeHD wrote: Tue May 13, 2025 10:11 am
nostalphia wrote: Tue May 13, 2025 10:03 am p.s, I haven't found a way to upload .blend files yet, maybe I could get your email address?
You can attach files directly to messages in this board, including .blend files.

The same with images, you don't need to use postimages.cc!
:lol: thx
the file too large 2.2Mb (if include texture), I have to upload .blend to this board,texture to that .cc website :D
geneva waves.blend
(945.49 KiB) Downloaded 273 times
with the textureImage
nostalphia
Posts: 5
Joined: Sun May 11, 2025 4:38 pm

Re: Luxcore really needs an anisotropic rotation option

Post by nostalphia »

CodeHD wrote: Mon May 12, 2025 8:35 am
nostalphia wrote: Sun May 11, 2025 6:42 pm ...
(Adding subD (level 3) to the circular texture brings terrible saw aliasings)

but it becomes difficult when cannot changing the uv for some reason
in the U/V workflow, the u-rough = v-rough of Apoint and Bpoint(two points at ±45°) , who should be opposite value :o .
Hello,

Could you explain this in a little more detail, please?
For example, about the second issue, can you show a comparison of how it is supposed to look?
Ideally, always include a blend file (simple and with textures included) so that your setup can be better understood.
there is another example to explain the convenience of{anisotropic rotation} in dealing with certain situations:
1.jpg
A metal ball with many very slight scratches. When the ball reflects the highlight of the light source, the scratches around the highlight (although their directions are randomly distributed) are also partially illuminated, but always appear to be rotating around the highlight.
scratches in blender viewport:
2.jpg
Anisotropic rotation calculated by node in blender viewport:
3.jpg
texture file:
Image
the .blend file:
Messy scratches.blend
(1.83 MiB) Downloaded 254 times
======================================================
using [Vector Brush] or [Flow Map Painting] by Mari or Substance Painter, to get the RG two-color map with scratch direction information, and then get the anisotropic rotation map through node calculation:
4.jpg
(in some renderer may add 0.25 at the end)
Post Reply