strands don't start at particle position

[seb4d]

Hi everyone !

I am working on a close up shot of optical fibers and used ICE strands to generate them.
I want to focus on the beginning of the strands, where they are generated from the point cloud (represented by the grid mesh).
My problem is that the strands don't "touch" the particles from where they are generated, as you can see on the image.
I can make it better by adjusting the "Num Segments" parameter, but it makes my scene very heavy and doesn't really solve the problem.

Any idea how to do it ?

[Mathaeus]

Are you are able to see ICE strand starting directly from particle, in view port, but not in renderer. If so, most likely, this is behavior of renderer, who omits the particle position when creates the strands. Usually this is behavior of Arnold renderer. It's possible to compensate this, by using a few small compounds from Melena. I think this is something like 'get array ratio' > 'get position on strand'> set strandposition (both are Melena compounds).

Anyway, if I'm correct with all what I said, this is not a bug on SI side, more an intentionally unusual behavior of Arnold. At least would be nice from Arnold side (or any else renderer with such practice), to provide these workarounds with install, or in another way.

[seb4d]

Yes this is only in renderer.
I will try to play with melena compound to see if I managed to solve my problem.
Thanks for your help !

[forton]

This helps normally, put it like this image in your last execute port, it adds the pointposition as first value to your strandpositions.

strands.jpeg

Cheers!

[seb4d]

WOW !
It works like a charm Forton !!
Exactly what I needed, thank you very much

[forton]

You're welcome!

[forton]

What I forgot to mention, arnold (or was it emtopolizer I'm not sure) wants you to have some other arrays like strandsize have the same size as strandposition, so if you get an error do the same thing with these.