Cineversity

Has anybody noticed hair being pretty buggy with the tracer object?  Maybe it is to be expected, but I feel like the results are all over the place, sometimes I get hair dynamics, sometimes I don’t, the guides don’t update properly, the Hair attributes windows flashes as the preview plays etc…

I assume it because the spline is being created and hair is trying to keep up with it?

Hi Alex,

If you have a reduced scene file, just the object that is traced, the Tracer and the material, please share it, perhaps via PM and dropbox if it is NDA based.

The Tracer needs always to build up its “Spline”. It is not possible to scrub the timeline. The first thing that I would try is the Object Manager>Tags> Hair> Hair Render Tag> Mode set to Line.

I haven’t found any hard evidence yet, but my “gut-feeling” tells me always to test the settings “Intermediate points” for the Tracer as well. All I can say, it changes the outcome. Again, might be bogus in this case.

You should place a spline object close to it, to have a comparison, if it is at all the Tracer.

I assume you have set up the Hair materials properly. Just in case, check the Illumination tab of the hair Material. As in the other thread, I will post a little screen shot about. Perhaps the Roughness slider is all there is to this problem.

All the best

Hi Sassi

Thanks for the reply.
Here is a super simple scene file.  The render tag seems to smooth things out a bit, and a C4d restart also made things a bit better (no more flashing of the Hair attribute manager).

https://www.dropbox.com/s/sentufaj7fwf6k6/HairOnSpline.c4d?dl=0

But what I’m seeing now is that the hairs are indeed growing on the tracer, but they have no dynamics…Is that due to the tracer?  Because I put another spline right next to it, and in that one I can see the dynamics working fine…

Let me know if my file makes sense…

Thanks!

Interesting, I was taking about the Hair material, Alex, But yes, you indicated the Guides. Hence the scene file speaks a clear language and why it is really the best way. It is such a waste of everyones time to assume and not to look at a scene.

I can’t reproduce here any problem, even if I left the Object Manager as I got it. ALWAYS top to bottom hierarchy. Information flow. (BTW, why is there always an Foreground Element in it, Given the idea of a reduced scene, this gives me no clue, I ignore it, but it baffles me alawys.)

Tracer and progressively added Hair:
The tracer produces Dynamic Hair, but just for one frame, then it updates everything. So it doesn’t look like dyn-hair. Sometimes you can see a little bit of it—dynamic. I have to come back to that later, and check if I find something useable for such an set up. As it is now, no way.

Dynamics:
Use the Cache to get constant results, if there is a problem, but I get it, this was set as a reference. Try to do a cache on the Tracer set up and it fails, at least it does it here. Hair was not really designed for that…

All the best

Hi Sassi

Ok, I understand.  Thanks for looking into it.

The Foreground object is always in my scenes because I have it setup in my “new.c4d” file.  What it does is essentially prevent the Render Preview from rendering anything that is not already part of my Width/Height in the Output tab of the render settings.
It is always a bit frustrating to me to wait and see pixels render in the preview that I won’t see in the final output, so I set it up like that, just a FG object with a texture that has a solid color in the alpha channel…

Thanks again Sassi, I’ll work on a different system to have this effect I was looking for with the tracer.

Alex

You’re welcome, Alex.

If you would describe what the final target should look like…

I always hope to find something that works, even in the past there was no answer for it, but things change, so I try again.

:o)

Alex, I think I got something useful.

Think about our discussion earlier in an other thread about Feather
http://www.cineversity.com/forums/viewthread/1917/#7242

With this already in mind, use the tracer to create a spline (Animate>Play Mode>Simple) and let the Tracer work from start to the last moving frame. If you let run it long, and no movement is given, it just adds points and destroys the solve)

This Tracer needs to be copied and then this copy need to be made editable. This spline is now used in Hair, as you need it.

The progression comes with the “Feather” UV setting. In the example I have used a Gradient in the Transparency channel. This last gradient (in V) is animated and unveils so the Hair as the Cube-Tracer combination would have done it. The Color Channel, if needed is perhaps another discussion…

Now the Dynamics work, and you can even use other “normal” Hair influences and Cache!

https://www.amazon.com/clouddrive/share/76pVHhECAFBo6XoVjUv6aSCQehh75EIZq161uTDhnQE?ref_=cd_ph_share_link_copy

A rendered version of it (I down sampled an UHD to HD):
https://www.amazon.com/clouddrive/share/oI7cYG7uzG9rOjnMusAjMXM6DxXqiGGrywfCW6sxcfu?ref_=cd_ph_share_link_copy

Just render the example and see for yourself.

ENJOY

P.S.: I had an example in the post above, but I hope this is a little bit more clear. Since the use of Hair is these days mostly not really character based, I thought it was interesting to dive a little bit deeper. In any case, this is not documented, so please test it for the individual use. I use here a 3D gradient, which is kind of tricky. Some of the 3D Gradients showed interesting results with fizzy hair.

I hope this works for you, as it keeps the progress of the appearance and the dynamic in tact.

https://www.amazon.com/clouddrive/share/Ir9en4zW8FofKEpKlGl4tczT1wH0QtAyeBIXApZImyH?ref_=cd_ph_share_link_copy

Signal
from Alex Czetwertynski

Please have a look:

https://vimeo.com/158411855

A video commissioned by Samsung for their new 837NYC space (#837NYC).
It was designed for a 30ft tall video wall, so please watch full screen and with headphones.
Sound Design : Andrew Potter
Guitar : Daniel Kim