Vray next (also update2) + Hair and Fur multiple nodes/modifiers Bug

[cedeee]

Hello,

I'm having a quite annoying bug with the Hair and Fur modifier with Vray.

My object has 3 different hair and Fur modifiers on it, with each a polygon selection. All have a quite high count of hairs and multistrands.

The problem is that the hair and fur modifier on top doesn't render correctly. Lots of hair missing !

If I Move the modifier from place in the stack, the upper modifier Always renders buggy. See pics

Scanline render renders all of the hair.

I recreated the problem in a simplified scene with one sphere. Same problem.

Updated Vray to the update 2 but the problem persists

1trick is to make several instances of e.g. the sphere for each modifier, but I would prefer not too.

Anyone encountered the same issue?

Thanks

spec:

max 2019, vray next update2
Same problem with max 2020

Hair modifiers on test scene :

1: hairs 300k

seg. 10

renderpasses 2

multistrand 8

2: hairs 500k

seg. 15
renderpasses 4

multistrand 10

3: hairs 500k

seg. 10
renderpasses 1

multistrand 2

[vlado]

I will ask someone to try and reproduce this here.

Best regards,
Vlado

[cedeee]

Thanks, let me know !

[Margarita.Stoeva]

Hello!

I tried to reproduce your issue but with no luck so far.
Could you please send us the simple scene for testing - the one that demonstrates the hairs distribution on a Sphere? It will help us a lot.
You can send it to me - margarita.stoeva@chaosgroup.com
Thank you!

Best regards,
Margarita

[Margarita.Stoeva]

Thank you for your scene! I just tested it.
Unfortunately, I confirm I can reproduce the issue with it now. I'll forward it to our developers to look into.
I'll let you know if I can think of another workaround than the one you suggested.

Best regards,
Margarita

[cedeee]

Ok super! I hope it can get fixed fairly rapidly. Thanx!

[cedeee]

Thank you for your scene! I just tested it.
Unfortunately, I confirm I can reproduce the issue with it now. I'll forward it to our developers to look into.
I'll let you know if I can think of another workaround than the one you suggested.

Best regards,
Margarita

Hello Margarita,
Do you have perhaps any update on this?
Thank you

[Margarita.Stoeva]

Hello!

I'm sorry to say that we have not developed a fix for this this yet.

Your issue is logged with number VMAX-8853 in our bug tracking system - feel free to use this reference.
I suspect the timing is no good for you because you mentioned that you hoped for a rapid fix. Until our developers get to this issue you may want to check the VRayFur or try Ornatrix in your scene?
Look into the VRayFur example I attach. I tried to make it look similar but further enhancements can be done.

VRayFur_2019.zip


Best regards,
Margarita

[cedeee]

Hello Margarita,
Could you tell me where I can check the bug tracking system?

I Don't think VrayFur would be suitable for my project. (Maybe for the test scene but not enough controls for an animal).
I know Ornatrix, but my workflow here is with Hair 'n fur. (no plugins, except vray of course )

I used now the trick of having multiple meshes, but I can not work further with this method neither present it this way to my clients.

Thank anyhow of taking the effort of re-making the scene with VrayFur, but this was just the test scene to reproduce the bug.

Thanks!

[Margarita.Stoeva]

Hello!

I'm sorry that the workaround didn't help for your project. I hope you have managed to complete it in some other way.

About our bug tracking system - there is no public access to it. The issue number I shared was for making it easier to reference your case with the logged entry.
(And I can check and inform you that there's no development progress on it yet.)

If you have the time, I would appreciate if you could share some experience on the features you miss the most in VRayFur.
I agree it's not as powerful in shaping hairstyles as the plugins specialized for this exact purpose but probably some improvements may be considered if suggested.
Also, you may want to check out the VRayFur styler if you think it may be useful to you: https://docs.chaosgroup.com/display/VRAY4MAX/Misc+Tools


Best regards
Margarita

[cedeee]

Hello Margarita,
Can I still expect any fix for this? Or is it a lost cause?
Thanks

[Margarita.Stoeva]

Hello!

I apologise for the late reply (shame on me).
Unfortunately there is no fix developed for your case yet so I asked our devepolers to make time and look into it again.

Best regards,
Margarita

[alexander.kazandzhiev]

Hi,

I was looking into this issue. But while I was playing with the scene I've noticed that if I reduce the hairs counts by 10 for all 3 modifiers they start to render properly. Also while I was playing the hairs distribution gets wrong from time to time with the big hairs counts. So I decided to test the scene with ART Renderer as more native to Max and got the same result (screenshot attached) so I think this is more of an issue with the Hair and Fur itself. Can you check it at your side to confirm the results with ART or something else please?
Another thing that may be a problem is that in the sample scene the Hair and Fur effect was using "buffer" instead of "mr prim" hairs type. As described here https://docs.chaosgroup.com/display/...d+Fur+Modifier "mr prim" is the type used to render the hairs as native V-Ray geometry. In this mode Hair and Fur generates the hairs and gives the raw data to V-Ray, so the hairs are treated as hair objects. Can you check if that would improve the results?

Best regards,
Alexander