Volume trail strand UVs?

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Hey guys, what is teh way to apply UVs on volume trail strand primitives please? TO get black at the start of the strand and white at the end for instance?

Cheers,

A.
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Use a uvtexture SOP and set the texture type to rows and columns.
Dont forget to set the attribute class to points if you want to manipulate them.
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Hey Man, thanks for the help. I'm somehow getting something now along the length of the strands following your inputs. Although i have no clue where those colors come from (see first pic).

I'm using an attribute from map to generate colors per strand, and it shows in my viewport. But somehow i'm not managing to forward that attribute color to the redshift user data color node (or even the redshift point attribute node). It just won't use that color at render time. I made sure to promote that Cd attribute in the RS obj parameters, but nothing.

Furthermore, i'm trying to mix what you helped me with, re-map /use a ramp on the length of the strands, and multiply / mix it with the color from the attribute from map. I've been tweaking things around but can't seem to get anywhere.

Cheers,

A.
Edited by Adriano - March 12, 2017 10:16:21

Attachments:
WolumeTrailsRowsandColumns.JPG (81.5 KB)
WolumeTrails2.JPG (74.8 KB)
VolumeTrails3.JPG (242.9 KB)

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Hey.
Cant help you with the redshift problem.

The colors in your viewport and the render looks like the visualization colors from the volume trail node. Try turn it of.

Also, keep in mind that the volume trail SOP doesn´t promote attributes from the incomming points. Only the first point in the primitive will get the assigned value, you will have to promote them from there using the first match method.
Ill post a RFE for the volume trail to carry attributes thru.
Edited by mawi - March 12, 2017 17:30:42

Attachments:
vTrail.hiplc (113.7 KB)

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Thanks a bunch, man. Great stuff. interesting approach. I was following that tuts from the Entagma guys, amazing resource as well. So many ways to go at it in Houdini, it's quite impressive.

Thanks for the tips.

A.
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I was able to color volume trails in Redshift by first promoting the Cd attribute to primitives as a way to color each strand, then promote again from primitive to point, passing the strand color back to each point, which can then be read in from Redshift via an RS Point Attribute node in a material/shop network.

Attachments:
colorTrails.png (1.2 MB)

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