Color channel of the Redshift material volume node issue...

[Masoud]

Hi guys,

I would like to use the color channel of the Redshift's material volume node.

1) I created a vector point attribute called "absorption".

2) I added this attribute's name to the "Volume Rasterize Attribute", attributes list, to create a volume called "absorption"

3) In the "volume source" node of my pyro DOP, I added "absorption" as the source and target field (as vector type).

4) I add a "VDB vector merge" node before my pyro material node.

5) In the RS Volume material, I add "absorption name into the color channel.

 

But it doesn't work..! How can I fix it?

 

Thanks for helping.

Absorption_01.hip

[flcc]

After your vdbvectormerge there is only two volume : density and vel.
Thus in the color channel field you can't use absorbtion, just density or vel.

 

[Masoud]

Hi Fred,

Your right, I add it, but it still doesn't work!

[flcc]

What I do know is that the channel works the way you use it. Just enter the name of a volume that works to try.
If you enter density, heat or temperature, which obviously must be present after the VDB conversion you will see that it works fine.
Now I'm not really a pyro user. Just my two pence guess : I don't see where in the DOP network, the absorption volume is processed by the pyro solver.
Maybe it's just that all the values are zero.
In my opinion this is where you should look.

 

Edited April 16, 2022 by flcc

[Masoud]

Any more ideas?

[Ziyad]

Hello, 

Like Fred suggested, your absorption vector attribute has 0 values, hence why it's not showing anything.

Give the absorption attribute a value like {1,0,0} then use the Dop I/O node to import the volume fields including the absorption. You should then be able to see it working. 

 

[Masoud]

Hi Ziyad,

Thanks for the reply. In the Volume Source, I turned the "Enlarge Fields to Contain Source" ON, and the problem was solved.