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Hi,

I've modeled a lot of art in VR using tiltbrush flat brush. This creates a ribbon with a vertex color and none of the other effects usually seen in tiltbrush.

I've been able to work flawlessly with Corona before by creating a super simple material that extracts the vertex colors and applies it to the ribbons. So far, I've not been able to achieve the same results with Octane:
Here is the test file from Tiltbrush:
I've followed the instructions illustrated here:
https://docs.otoy.com/3DSMaxH/3DSMaxPlu ... ribute.htm
1-Set the object to moveable proxy
2-Set up the material as illustrated above
3-Set MapChannel to 0 in the parameters
4-Applied the material to the object

I keep getting grey renders when it should be blue. I am wondering if anyone could assist me with this issue. Thank you in advance!

Solved it!

For some reason it does not work in the Diffuse material, but it works if you plug the vertex into a Universal material's Albedo!

Thanks for sharing

Hi SamuelAB,
As I can see in your screenshot, you are using a diffuse layer instead of a diffuse material, you would connect material layer to Octane material.
Regards
Paride

You are right, I was initially using the wrong kind of material

Actually I'd like to update this thread. I said the vertex show up, but they show up wrong. If you only have one Tiltbrush color it is fine, but otherwise, the colors are all wrong and at the wrong location.
I still have to still have to do some research to get it right.

Hi SamuelAB,
could you share an Octane material made with Tiltbrush?
Regards
Paride

Hi Paride,

My material is the same as in post # 2, with a vertex color in Albedo. But the problem is a bit more complicated than that. The vertex colors of Tiltbrush files were not meant to be read as is. Tiltbrush was made to be read in Unity and Google open sourced the code so you can do your own shader if you want it supported in other applications.

You can read about it here:
https://support.google.com/tiltbrush/th ... 5102?hl=en
https://support.google.com/tiltbrush/th ... 3994?hl=en

Some hints as to how the vertex colors are distributed:

"colors in Tilt Brush are set using vertex colors so a single batch may contain many colors. You would have to write your own code to split them by color."
"I am able to re-export the mesh from Houdiniby promoting the point class to the vertex class as below:"

-

I do have a second problem as well. I am able to pull out this incorrect vector color data in 3ds Max by following the steps in my first post above, but I am not able to do this in Unity's Octane or in Octane standalone when I export the scene from Unity.

To get the vectors to show up in 3ds Max's Octane, I have to do this:
1-Set the object to moveable proxy
2-Set up the material as illustrated above
3-Set MapChannel to 0 in the parameters
4-Apply the material to the object

However in Unity's Octane and in the exported Standalone file, there is no option for setting the object to a moveable proxy. The color vertex geometry is always just white.

Hi SamuelAB,
did you try to export an .orbx from from Houdini?
Regards
Paride

I have not tried this yet since I've never used Houdini. I may try the free version, but I feel I will get lost pretty quickly, especially if I try to recreate what this person did.