imported alembic hair UV

[zullup]

Hey!

Just tried importing hair as an alembic into c4d from maya/yeti. The curves are there and rendering but I can't manage to texture them. It seems like octane does not
now how to read the UVs? (yeti exports UV data to the alembic).
It should have the growth surface UV for proper fur texturing but I can't make it work.

I tried importing them as curves and used an octane tag with "render as hair" and I also imported as c4d hair which does not make any difference.
I hope you can help me!

kind regards

[jayroth2020]

It depends on how you have structured your hair material. Octane has a W Coordinate node that is used to apply color through the hair strand. Place a simplified version of your scene here so that we can take a look, or file a support ticket — [email protected]

[zullup]

Hey.

I do not have any problms with W coordinates... that works fine.
I want it to get texturing from the growth surface textures. In this example each strand should adopt the color from the underlaying surface when surface and hair have the same texture applied.

Dropbox link: https://www.dropbox.com/sh/ge17um8cmgmt ... iT5Oa?dl=0
(viewport visibility is off for the hair for performance reasons)

Yeti exports .abc with UVs so it should actually work like that.


kind regards!

[jobigoud]

I loaded your Alembic in Octane standalone and applied a UV test texture and got the expected result.

[zullup]

Yes, this looks like I want it to look. Unfortunately I am using C4D, have you tried the same in there?

[zullup]

BTw. I also checked in Standalone and it works over there but NO luck in c4d.
Is this something that was just not implemented in the plugin?

It also seems like the standalone automatically interprets the with attribute right which is awesome.
I really need this to work in the c4d plugin tho...

[aoktar]

Hey.

I do not have any problms with W coordinates... that works fine.
I want it to get texturing from the growth surface textures. In this example each strand should adopt the color from the underlaying surface when surface and hair have the same texture applied.

Dropbox link: https://www.dropbox.com/sh/ge17um8cmgmt ... iT5Oa?dl=0
(viewport visibility is off for the hair for performance reasons)

Yeti exports .abc with UVs so it should actually work like that.


kind regards!

I cannot get it work with standard renderer too. Can you?

[zullup]

I cannot get it work with standard renderer too. Can you?

I am not really familiar with the native c4d shading/rendering stuff but using a c4d hairshader and putting textures to "root" in the color section also does NOT do anything when rendered with "standard".
It really looks like c4d does not know what to do with the UV attributes of the imported curves which is absolutely crazy.

Can you with your deep knowledge can see if c4d somewhere reads the per strand attributes that are stored in the alembic? Maybe there is a workaround if c4d reads them but does not interpret it in any way.


thank you!

[aoktar]

I cannot get it work with standard renderer too. Can you?

I am not really familiar with the native c4d shading/rendering stuff but using a c4d hairshader and putting textures to "root" in the color section also does NOT do anything when rendered with "standard".
It really looks like c4d does not know what to do with the UV attributes of the imported curves which is absolutely crazy.

Can you with your deep knowledge can see if c4d somewhere reads the per strand attributes that are stored in the alembic? Maybe there is a workaround if c4d reads them but does not interpret it in any way.


thank you!

That's not a matter how you generate a hair. It should have some UV coordinates in C4D. Then our plugin will export it. Here alembic doesn't appear to have it, you can test it by UV kernel. Also tested this geometry with Standard Renderer and it still doesn't give mapped results. So issue is not on Octane plugin, on how you import that.

[zullup]

[/quote]
That's not a matter how you generate a hair. It should have some UV coordinates in C4D. Then our plugin will export it. Here alembic doesn't appear to have it, you can test it by UV kernel. Also tested this geometry with Standard Renderer and it still doesn't give mapped results. So issue is not on Octane plugin, on how you import that.[/quote]

Since it renders perfectly using this very alembic with the standalone but is not rendering correctly using the Standard renderer it seems like C4D just does not import the UVs correctly, right?
Is there anything we can do here like a direct passthrough of the .abc to the renderer without having c4d messing it up?