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Hello again.

I want to get attributes from SOP to use them for material customization.

I can attach float attributes through the "Float_Vertex_Attribute" node with no problem.
But I have no way to see any vector attributes (except the built-in color attribute) with "Vector_Vertex_Attribute".

What is the correct way to output/get vector attributes?

michaelskripin wrote:Hello again.

I want to get attributes from SOP to use them for material customization.

I can attach float attributes through the "Float_Vertex_Attribute" node with no problem.
But I have no way to see any vector attributes (except the built-in color attribute) with "Vector_Vertex_Attribute".

What is the correct way to output/get vector attributes?

Hi Michael,

Thanks for the post again. We have made all two named vertex color arrays and four named float arrays dynamic so Houdini can read the vertex arrays.
Btw, have you also checked the name change in LOP workflow?

https://www.sidefx.com/docs/houdini/sol ... mport.html


cheers

Hi. I checked the attribute mapping in Arnold and Karma - everything works fine.

Let me show you a simple example of how I work with Octane.

In "sop create" I create a simple "grid". I create float and vector attributes for it. When I connect "float_vertex_attribute" to "baseColor", I can see in the viewer that the attributes are displayed in the material. When I connect "color_vertex_attribute" to "baseColor", nothing happens. Where am I making a mistake?
I attach a hip file just in case.

This is interesting. Same scene, but I added a "scatter" node after the grid.
Float attribute, which was displayed on the surface of the grid when rendering,
is no longer displayed on the points. What is the trick?

michaelskripin wrote:Hi. I checked the attribute mapping in Arnold and Karma - everything works fine.

Let me show you a simple example of how I work with Octane.

In "sop create" I create a simple "grid". I create float and vector attributes for it.

Screenshot 2024-05-03 at 14.13.37.png

Screenshot 2024-05-03 at 14.13.47.png

When I connect "float_vertex_attribute" to "baseColor", I can see in the viewer that the attributes are displayed in the material.

Screenshot 2024-05-03 at 14.15.34.png

When I connect "color_vertex_attribute" to "baseColor", nothing happens.

Screenshot 2024-05-03 at 14.15.50.png

Where am I making a mistake?
I attach a hip file just in case.

Hi Michael,

Thank you for reporting this issue.
We have fixed this for the next release.

Regarding the scatter issue, could you try using Texture instance color node and assign the *alpha4k_map.ppm* from the plugin's *tex* folder?

cheers

BK wrote:
Regarding the scatter issue, could you try using Texture instance color node and assign the *alpha4k_map.ppm* from the plugin's *tex* folder?

cheers

Hi BK,

I attached the "Texture instance color" with "alpha4k_map.ppm" to the "Base color" of the "Standard surface" node.
I'm not sure what the result should be, but nothing seems to be happening.


Update.
Texture instance color works as expected.

I must have made a mistake somewhere. My bad.

Random color works as expected too.

Attributes didn't work. I rechecked several times.

michaelskripin wrote:

BK wrote:
Regarding the scatter issue, could you try using Texture instance color node and assign the *alpha4k_map.ppm* from the plugin's *tex* folder?

cheers

Hi BK,

I attached the "Texture instance color" with "alpha4k_map.ppm" to the "Base color" of the "Standard surface" node.
I'm not sure what the result should be, but nothing seems to be happening.


Update.
Texture instance color works as expected.

I must have made a mistake somewhere. My bad.

Random color works as expected too.

Attributes didn't work. I rechecked several times.

Thank you Michael,
Glad to know the random color works as expected.
we will investigate further on attribute issues.

Cheers