Chaos Corona Forum

General Category => Gallery => Work in Progress/Tests => Topic started by: maru on 2017-07-05, 12:00:36

Title: 1.7 - Hair shader playground and feedback
Post by: maru on 2017-07-05, 12:00:36
Let's share our tests and for fun renders with the new hair shader here!
You can get the newest daily build with hair support here: https://coronarenderer.freshdesk.com/support/solutions/articles/5000570015-daily-builds

Just a few very simple tests for the beginning:

Default settings:
(https://forum.corona-renderer.com/index.php?action=dlattach;topic=16730.0;attach=66990;image) (https://forum.corona-renderer.com/index.php?action=dlattach;topic=16730.0;attach=66992;image)

Melanin = 0,25
(https://forum.corona-renderer.com/index.php?action=dlattach;topic=16730.0;attach=67014;image)

Melanin = 0,25; pheomelanin = 1
(https://forum.corona-renderer.com/index.php?action=dlattach;topic=16730.0;attach=67016;image)

Diffuse color altered:
(https://forum.corona-renderer.com/index.php?action=dlattach;topic=16730.0;attach=66994;image)

Glints = 1
(https://forum.corona-renderer.com/index.php?action=dlattach;topic=16730.0;attach=66996;image)

Glints = 0
(https://forum.corona-renderer.com/index.php?action=dlattach;topic=16730.0;attach=66998;image)

Glossiness = 0,8
(https://forum.corona-renderer.com/index.php?action=dlattach;topic=16730.0;attach=67006;image)

Glossiness = 0,2
(https://forum.corona-renderer.com/index.php?action=dlattach;topic=16730.0;attach=67000;image)

Glossiness = 0,2; softness = 0,2
(https://forum.corona-renderer.com/index.php?action=dlattach;topic=16730.0;attach=67002;image)

Glossiness = 0,2; softness = 0,5
(https://forum.corona-renderer.com/index.php?action=dlattach;topic=16730.0;attach=67004;image)

Highlight shift = 0
(https://forum.corona-renderer.com/index.php?action=dlattach;topic=16730.0;attach=67008;image)

Highlight shift = 2,5
(https://forum.corona-renderer.com/index.php?action=dlattach;topic=16730.0;attach=67012;image)

Highlight shift = 5
(https://forum.corona-renderer.com/index.php?action=dlattach;topic=16730.0;attach=67010;image)


Bonus!
(https://forum.corona-renderer.com/index.php?action=dlattach;topic=16730.0;attach=67018;image)



Title: Re: Hair shader playground and feedback
Post by: maru on 2017-07-05, 12:21:38
My only feedback so far is that lowering opacity makes rendering extremely slow.
Title: Re: Hair shader playground and feedback
Post by: zuliban on 2017-07-05, 19:10:36
looks like a fun material to play with, is highlight shift the same as anisotropy reflections?
Title: Re: Hair shader playground and feedback
Post by: JoeVallard on 2017-07-05, 20:09:43
Downloaded the hair farm demo and one of the example scenes. I did this back on the Jun 21st build and i'm not sure if anything has changed since then but i did have some strange issues with the GI precomp hanging when rendering the Hair material (both render and interactive render). Anyways the setting are slightly tweaked from the default shader.

@Maru ty for posting this its nice to see these kind of images to quickly show what each setting does.
Title: Re: Hair shader playground and feedback
Post by: cecofuli on 2017-07-05, 22:50:47
What about H&F shading? How can be possible to add material to 3ds max H&F?
Title: Re: Hair shader playground and feedback
Post by: ylucic on 2017-07-05, 23:03:34
not at all a technical test...but had fun doing it..
works well with a couples of lights..
the ones with black background only have and light in the zenith...and did a quick reference image with just a corona material with similar color to see what the shader did...

it would be nice to have support for native hair and fur for the this shader...to do other stuff besides hair

cheers!
Title: Re: Hair shader playground and feedback
Post by: Fritzlachatte on 2017-07-06, 16:51:53
Hi, all those images look interesting, but I don´t realy understand (in case of fur not hair) the advantage over a selfmade shader.
For rendering a pleasant fur plaid, it was more the absence of 100% utilizing AD Hair&Fur and having massive RAM flooding. The optic for itself was good enough, it was more the rude hair/fur structure, not the shader which bothered me and spit out low memory warnings like hell.
The only alternative seem to be Ornatrix or HairFarm, but I always had the wish corona would offer an inhouse solution like corona scatter instead of Forestpack.
What is the real benefit of the shader? Is it just for Hair in combination with e.g. DAZ 3D ?! If there would be an implementation of H&F like Vray etc. use, would H&F still remain as a RAM eater? 
Does Ornatrix handle this problem better? Lots of questions sorry.
Title: Re: Hair shader playground and feedback
Post by: maru on 2017-07-06, 16:57:22
Apart from the hair shader, which is physically plausible (it actually simulates how light reacts with real hair), Corona can now take advantage of instancing when rendering hair. So you can expect huge RAM saving when rendering hair now*. Keep in mind that all this hair related stuff is still WIP.

*devs, please correct me if I'm wrong
Title: Re: Hair shader playground and feedback
Post by: TomG on 2017-07-06, 17:52:08
As someone who does not know any of the details of the calculations involved (not being a coder!), there are two differences that are still visible to me about the hair material just from rendering it. The first is that it has transmission through the volume, somewhat like SSS, as can be seen in the image below with an array of regular cylinders lit by a sun.

The second is that the shape of the highlight is different, somewhat like anisotropy, as seen in the other image where the hair material is applied to a regular sphere.

And I am sure there is much more to it than that! But those are two visible differences that I hope show some ways that the hair material is different from any other sort of regular material (plus it has controls for melanin and pheomelanin to control color, has colorless and colored speculars, etc. - all of which makes it more suited to the task of rendering realistic hair and fur than regular materials).

Title: Re: Hair shader playground and feedback
Post by: TomG on 2017-07-06, 18:18:11
Nothing dramatic here, just wanted to have a scene with dynamics, so used the free sample scene from Ornatrix (https://ephere.com/plugins/autodesk/max/ornatrix/docs/5/Simple_Bird_With_Dynamic_Feathers.html (https://ephere.com/plugins/autodesk/max/ornatrix/docs/5/Simple_Bird_With_Dynamic_Feathers.html))  and went for a shiny metallic look for the bird using CoronaHair.

Aha found my test youtube, so uploaded it there:

Title: Re: Hair shader playground and feedback
Post by: Juraj on 2017-07-06, 19:30:25
Hi, all those images look interesting, but I don´t realy understand (in case of fur not hair) the advantage over a selfmade shader.

You definitely can't make certain materials using generic shader look convincing. Hair, Skin, Wood and certain rough materials have such different surface characteristic (multi-lobe specular response, special subsurface behavior, multi-directional anisotropy,etc..) that making them from generic shader will look wrong no matter how much effort is given to it.

That, and very nice default presets optimized for characteristic look.

All these weird, low-poly hair models make the shader look like from 1995 though :- ). Games running on PS4 (Rise of tomb raider, Uncharted 4, Horizon Zero Dawn) have higher fidelity in hair than this.
Title: Re: Hair shader playground and feedback
Post by: TomG on 2017-07-06, 20:01:55
All these weird, low-poly hair models make the shader look like from 1995 though :- ). Games running on PS4 (Rise of tomb raider, Uncharted 4, Horizon Zero Dawn) have higher fidelity in hair than this.

Yes, sadly I am brand new to Ornatrix, and have to rely on their free scenes for testing, just to see if things work :) Hopefully a hair artist will get into doing some testing and start showing how it all looks on some beautifully modeled hair! If anyone knows of any super-good models / scenes that come with good Ornatrix set ups, that would be awesome! I stopped my search for now with Ornatrix's own setups, just to get started :)
Title: Re: Hair shader playground and feedback
Post by: Fritzlachatte on 2017-07-07, 08:34:33
Thanks for all these demonstrative explenations.
I really have to play around with it to test the RAM saving aspect. But Juraj`s rude 90s comparison was my first impression as well, a little bit if Malibu Stacy refuses washing her hair.
But this shows clearly the need of addons like Ornatrix or a proper use of H&F ... or somewhere in the future "Corona Hairbrush 3000 "

Anyway thanks for explaining.
 
Title: Re: Hair shader playground and feedback
Post by: maru on 2017-07-07, 10:44:27
Better test object.
Checking the "render as planes" option, which is hidden in devel/debug rollout.
When enabled, rendering is much faster and with less noise, but the hair appear less realistic. Currently there also is an issue with Embree which may introduce some artifacts when this option is enabled.
Rendering for 2 minutes.
Title: Re: Hair shader playground and feedback
Post by: Juraj on 2017-07-07, 12:13:56
I would say that's super trade-off. I would rather render billion planes, I cannot tell the difference :- ). The AA is superior too.
Title: Re: Hair shader playground and feedback
Post by: Ludvik Koutny on 2017-07-07, 13:35:42
Shouldn't rendering as planes VS cylinders be considered per object in scene, not globally? :)
Title: Re: Hair shader playground and feedback
Post by: Bigguns on 2017-07-09, 23:12:09
I second that Rawalanche ^^ ** same thing for the tesselation, like facial hairs they are super short, I don't need them to be as tesselated as the long hairs etc. I guess it can optimise RAM that way and render time as well .
Title: Re: Hair shader playground and feedback
Post by: Ondra on 2017-07-10, 11:03:10
ok, lets end the broscience here ;)

I did tests on the biggun's hair model, with 65k strands. Tried different embree subdiv settings, from 1 to 16. Results:

memory usage was always the same. Subdiv settings are applied only during traversal

Performance, in Mrays/s:
Subdiv  1: 5.6
Subdiv 4: 5.2
Subdiv 8: 5.1
Subdiv 16: 4.2

So only going into extremes - single subdiv, or 16 subdivs - have some effect. I am tempted to increase the default subdiv to 8, as there is no peformance penalty - remember that the scene was JUST the haircut, nothing else - with other geometry, the impact would be negligible

Title: Re: Hair shader playground and feedback
Post by: ylucic on 2017-07-10, 21:35:20
Damn...those came out a bit "Trumpy" :S
Title: Re: Hair shader playground and feedback
Post by: cecofuli on 2017-07-11, 02:58:28
Ok, CoronaHairMtl now works with H&F.
But, is it normal, when I change some CoronaHairMtl (Diffuse Color, for example) I need to wait 10 second for the IR update?
It looks like Corona needs to rebuilt the hairs geometry structure, every time. 
It's very difficult to "play" with CoronaHairMtl in IR, because every shading change is so slow.

And, if I change the CoromaHairMtl opacity value (from 1 to 0.9, for example) I have ridiculous Rays/s speed (from 2 million to 100.000)
Title: Re: Hair shader playground and feedback
Post by: martinsik on 2017-07-11, 09:35:32
I have added a new poll that concerns how you control hair highlights size in CoronaHairMtl, please vote if this is important to you :)
Title: Re: Hair shader playground and feedback
Post by: martinsik on 2017-07-11, 09:39:00
looks like a fun material to play with, is highlight shift the same as anisotropy reflections?
Highlight shift can be though of as some sort of uniform bump mapping. In other words the normal is shifted by several degrees. This effect is here to simulate real hair fiber scales as seen on the image
Title: Re: Hair shader playground and feedback
Post by: martinsik on 2017-07-11, 09:42:32
Ok, CoronaHairMtl now works with H&F.
But, is it normal, when I change some CoronaHairMtl (Diffuse Color, for example) I need to wait 10 second for the IR update?
It looks like Corona needs to rebuilt the hairs geometry structure, every time. 
It's very difficult to "play" with CoronaHairMtl in IR, because every shading change is so slow.
In order to render Hair&Fur, all the hairs are first dump from 3ds max to a file and then loaded by Corona, that can take a pretty long time.

And, if I change the CoromaHairMtl opacity value (from 1 to 0.9, for example) I have ridiculous Rays/s speed (from 2 million to 100.000)
Yes, we are aware of this issue and will work on it. For now I recommend using opacity equal to 1 (it is also more physically correct).
Title: Re: Hair shader playground and feedback
Post by: cecofuli on 2017-07-11, 14:14:23
Thank you , Martin.
Maybe will we have some improvement about IR and H&F speed in the next release?
Or is it impossible, because 3ds max?
Title: Re: Hair shader playground and feedback
Post by: martinsik on 2017-07-11, 15:24:58
Maybe will we have some improvement about IR and H&F speed in the next release?
Or is it impossible, because 3ds max?
Unfortunately this is a limitation of Hair&Fur itself :(
Title: Re: Hair shader playground and feedback
Post by: romullus on 2017-07-11, 16:26:01
I like it CoronaHair very much. Never had chance to play with hair rendering much, so it's maybe good time to start doing it now :]
Title: Re: Hair shader playground and feedback
Post by: Fluss on 2017-07-11, 20:10:02
I'm starting some tests with the new hair shader. It seems to be quite slow. I've plugged the same map in both hair and diffuse color, everything else is set to defaults.

edit: dual xeon 2683 v3 (28 cores / 56 threads) @ 2.5GHz
Title: Re: Hair shader playground and feedback
Post by: Bigguns on 2017-07-11, 21:26:03
I'm starting some tests with the new hair shader. It seems to be quite slow. I've plugged the same map in both hair and diffuse color, everything else is set to defaults.

It's certainly not as fast as the corona Mtl, wich is normal, since hairs is a particular material and this one is really accurate high quality material wich produce great result. It's like a skin shader, these shaders are never fast .. or if they are.. they are not accurate and look super fake. You can't have the butter and the money of the butter as we say haha :)
Title: Re: Hair shader playground and feedback
Post by: Fluss on 2017-07-11, 21:41:15
Yes I know that. But 490 000 rays/s on a dual xeon 2683 v3 (so 28 cores / 56 threads), on approx. 1200x900px is really really slow.
Title: Re: Hair shader playground and feedback
Post by: Ludvik Koutny on 2017-07-11, 22:12:01
Yes I know that. But 490 000 rays/s on a dual xeon 2683 v3 (so 28 cores / 56 threads), on approx. 1200x900px is really really slow.
Make sure you are rendering hair as planes, not cylinders, and definitely make sure you are not using any opacity mapping. These two things can slow rendering down extremely.
Title: Re: Hair shader playground and feedback
Post by: Bigguns on 2017-07-11, 23:27:41
Yes I know that. But 490 000 rays/s on a dual xeon 2683 v3 (so 28 cores / 56 threads), on approx. 1200x900px is really really slow.

Like he said, don't use Opacity ! and you don't need opacity, this shader has super nice SSS build in to simulate real hair scattering.

and as a comparaison , in just a few minute I get this result , I don't know what you did wrong with you'r scene.. and I have only 4 cores 8 threads.. I7 2600k ..

Also, if you lit with an HDRI image, some will affect a lot the render time .. it's a thing to watch
Title: Re: Hair shader playground and feedback
Post by: cecofuli on 2017-07-12, 01:32:26
Why do I have this strange white dots? They are positioned on the hairs segments vertexes.
Also, I don't see any differences when I change the Curve Subdivs parameter.
In mantis a bug report with video: during the animations, I have some frames competently black.

(http://www.francescolegrenzi.com/Temp/Corona/0176_Fur_Bug.jpg)


Title: Re: Hair shader playground and feedback
Post by: Bigguns on 2017-07-12, 01:43:48
here's an other fur test .... dont ask me what it is ^^

Title: Re: Hair shader playground and feedback
Post by: Bigguns on 2017-07-12, 01:56:07
Why do I have this strange white dots? They are positioned on the hairs segments vertexes.
Also, I don't see any differences when I change the Curve Subdivs parameter.
In mantis a bug report with video: during the animations, I have some frames competently black.

(http://www.francescolegrenzi.com/Temp/Corona/0176_Fur_Bug.jpg)

cecofuli, I just did test and it's the glint that does that ... definately something to check in there I guess.. if you put it to zero it's ok. And BTW, the subdivs are there for hairfarm, if you use ahir and fur or ornatrix you don't need to touch it there.

Title: Re: Hair shader playground and feedback
Post by: marqueso on 2017-07-12, 02:23:06
Can this be used for grass or carpeting?
Title: Re: Hair shader playground and feedback
Post by: Bigguns on 2017-07-12, 02:38:49
hmm does grass or carpet are made of hairs ? lol it's not a tool for making actual hair, it's a shader to put on hairs or fur , it's different. If you'r capet is made of fur, like a bear carpet, then yes, if it's a fabric carpet, then you'r better with the coronaMtl .
Title: Re: Hair shader playground and feedback
Post by: Fluss on 2017-07-12, 09:26:24
Yes I know that. But 490 000 rays/s on a dual xeon 2683 v3 (so 28 cores / 56 threads), on approx. 1200x900px is really really slow.
Make sure you are rendering hair as planes, not cylinders, and definitely make sure you are not using any opacity mapping. These two things can slow rendering down extremely.

Hair passes parameter was the issue, it was set on 2 and needs to be set to 1. And there was no geometry under the Hair&Fur. killer combo...

That's way better now !

BTW, There is some uncleanable high noise on the ground. I guess it is introduced by hairMaterial as i never seen that kind of noise before. It seems to be more pronounced on cat's surronding

Title: Re: Hair shader playground and feedback
Post by: romullus on 2017-07-12, 09:54:57
Hair passes parameter was the issue, it was set on 2 and needs to be set to 1. And there was no geometry under the Hair&Fur. killer combo...

That's way better now !

BTW, There is some uncleanable high noise on the ground. I guess it is introduced by hairMaterial as i never seen that kind of noise before.

What hair solution do you use? In native H&F hair passes acts as simple multiplier for hair count. It shouldn't affect rendering speed much.
Title: Re: Hair shader playground and feedback
Post by: Bigguns on 2017-07-12, 10:05:10
Some new and older tests

Title: Re: Hair shader playground and feedback
Post by: Fluss on 2017-07-12, 10:15:52
Hair passes parameter was the issue, it was set on 2 and needs to be set to 1. And there was no geometry under the Hair&Fur. killer combo...

That's way better now !

BTW, There is some uncleanable high noise on the ground. I guess it is introduced by hairMaterial as i never seen that kind of noise before.

What hair solution do you use? In native H&F hair passes acts as simple multiplier for hair count. It shouldn't affect rendering speed much.

Max H&F
Title: Re: Hair shader playground and feedback
Post by: romullus on 2017-07-12, 10:20:41
Max H&F

Could you tell how did you achieve mapping to work then? For me H&F mapping doesn't work with Corona.
Title: Re: Hair shader playground and feedback
Post by: Fluss on 2017-07-12, 10:49:15
Max H&F

Could you tell how did you achieve mapping to work then? For me H&F mapping doesn't work with Corona.

It's a downloaded assset but from what i see, it is mapped on the base geometry then in H&F material parameters, diffuse is plugged in tip color and root color.
Title: Re: Hair shader playground and feedback
Post by: romullus on 2017-07-12, 10:58:03
Right, but hair is still H&F or is it converted to mesh/splines? i can plug maps in whatever hair material's slots and it doesn't work except for 3d procedural ones which doesn't need UV coordinates.

Can anyone else confirm if H&F mapping is picked up by Corona or not?
Title: Re: Hair shader playground and feedback
Post by: Fluss on 2017-07-12, 11:02:47
It' still H&F, rendering set to geometry in Env effects.
Title: Re: Hair shader playground and feedback
Post by: romullus on 2017-07-12, 11:14:34
Hmm, i think i found what it is. You're not using CoronaHair material in H&F mr parameters, right? I think it's wrong approach, although it seems to respect mapping and gives some remote possibility to colorize hair, but you loose all hair material controls and overal result looks much worse. I guess we need to wait for full and proper H&F support to be implemented.
Title: Re: Hair shader playground and feedback
Post by: Fluss on 2017-07-12, 11:17:09
No, Hair material is applied on the base mesh, not in the MR shader, simply because it's not a MR shader. So this is why i'm not able to get those nice specular effects !
Title: Re: Hair shader playground and feedback
Post by: Bigguns on 2017-07-12, 11:40:48
No, Hair material is applied on the base mesh, not in the MR shader, simply because it's not a MR shader. So this is why i'm not able to get those nice specular effects !

Yes, don't render the hairs as geometry the shader is made to work from spline generated either by Hand F ornatrix or hairfarm.. but not on poly.. like he said, you'r loosing all the nice effect of the shading... would look WAYYY better with not rendering with geometry :)
Title: Re: Hair shader playground and feedback
Post by: Fluss on 2017-07-12, 11:48:05
So i have to set the H&F env. effect to buffer instead of geometry ?
Title: Re: Hair shader playground and feedback
Post by: Fluss on 2017-07-12, 12:37:49
Well i left H&F env. effect as geometry but I've plugged coronaHairMtl into the MR shader, it seems to be set up correctly now and i confirm that mapping does not work that way. Hair passes have now way less influence over render time, i've set it to 3 and still have good performances. I have to say i'm pretty impressed by this shader right now, here is what i got.
Title: Re: Hair shader playground and feedback
Post by: cecofuli on 2017-07-12, 13:16:54
Bigguns, we cannot insert 0 as Curve subdivs. with 1, I have this strange white dots on every vertex.
I think it's a bug. also, you wrote to put "zero" to avoid the white dots. But.. in which option =) ?

And, I have discover that "Curves subdivs" works also with H&F =)
Title: Re: Hair shader playground and feedback
Post by: romullus on 2017-07-12, 14:13:55
So i have to set the H&F env. effect to buffer instead of geometry ?

As far as i can tell, settings in env. effects tab has no influence on Corona hair implementation, so you can leave it as it is.
Title: Re: Hair shader playground and feedback
Post by: Ondra on 2017-07-12, 14:29:37
Low Rays/s can be caused by HairFarm atmospherics effect - disable hairfarm renderer and/or disable atmospherics in common renderer settings to get 10x speed boost.

Cecofuli: no difference when changing subdivs is probably because your hair already have way too many subdivs from 3ds max - there is no more quality to gain

Is it just me, or does the cat looks kinda dead? ;)
Title: Re: Hair shader playground and feedback
Post by: Fluss on 2017-07-12, 14:32:43
Some minor adjustment on the dead cat, the shader is promising.
Title: Re: Hair shader playground and feedback
Post by: Fritzlachatte on 2017-07-12, 14:52:59
looks like some hair is missing along the grey fur gaps. Furthermore the fur looks quite scruffy "unstroked" and those extincted eyes look like the cat is more than sleeping.
But anyway, leaving the "dead cat" on cobblestones is way to cruel, it looks like passed over by a car... not funny.
 
Title: Re: Hair shader playground and feedback
Post by: maru on 2017-07-12, 14:57:13
hmm does grass or carpet are made of hairs ? lol it's not a tool for making actual hair, it's a shader to put on hairs or fur , it's different. If you'r capet is made of fur, like a bear carpet, then yes, if it's a fabric carpet, then you'r better with the coronaMtl .
Well if you look at a carpet close enough, you will most probably see that it's made of fibers which are pretty much hair-like (they scatter light, are reflective, etc), so if you need super high quality carpet for close ups, I think there is nothing wrong with using hair plugins with hair shader for that. But generally you can usually get away with scattering some strands and standard Corona material.
I wonder if there is any way to make a grass field with some hair plugin + hair shader. I can't really think of any benefits from doing that, but who knows... As far as I know Ornatrix can be used to scatter trees, grass, or other plants.

Just a note on using 3ds H&F modifier: just forget about the effects dialog. Leave those settings at defaults. Then plug Corona's hair mtl into the mr shader slot. That's the only workflow for now.
Title: Re: Hair shader playground and feedback
Post by: cecofuli on 2017-07-12, 15:01:19
Ok about the white dots: if, in the H&F I use a standard CoronaMtl with glossy, no problem at all.
The problem appear when I use CoronaHairMtl. Try to play with Glints Strenght value, with your hairs are big like a small tubes.
Title: Re: Hair shader playground and feedback
Post by: maru on 2017-07-12, 15:26:49
Ok about the white dots: if, in the H&F I use a standard CoronaMtl with glossy, no problem at all.
The problem appear when I use CoronaHairMtl. Try to play with Glints Strenght value, with your hairs are big like a small tubes.
We have to wait for martinsik to take a look at this and tell us what it is. It could be a bug. It could be an intended feature.
Title: Re: Hair shader playground and feedback
Post by: romullus on 2017-07-12, 15:30:16
Is it just me, or does the cat looks kinda dead? ;)

You're not alone, there's entire topic in the forum about this cat: https://www.dropbox.com/s/jfyhupz2ut9j3wt/04%20rubai%20melyna.png?dl=0

And now, since Corona hair does not support H&F UV mapping, our little friend looks like he was treated with bleacher o_O
Title: Re: Hair shader playground and feedback
Post by: Fluss on 2017-07-12, 15:48:12
Just to leave any ambiguity, i added some details... Enjoy ! I have to leave now, PETA foundation is knocking on my door

Ps : feel free to use it as splash screen for the 1.7 corona installer (a splash screen will never have been as well named)
Title: Re: Hair shader playground and feedback
Post by: martinsik on 2017-07-12, 15:54:30
Ok about the white dots: if, in the H&F I use a standard CoronaMtl with glossy, no problem at all.
The problem appear when I use CoronaHairMtl. Try to play with Glints Strenght value, with your hairs are big like a small tubes.
The dots are inteded irregularities introduced by the glint parameter. If you want to remove these irregularities set glint strength to 0.
Anyway, the hair shader is mostly intended for hair fibers that are much smaller in the image :)
Title: Re: Hair shader playground and feedback
Post by: cecofuli on 2017-07-12, 15:56:26
Thanks you, Martin. Finally I understand =)
Title: Re: Hair shader playground and feedback
Post by: Bigguns on 2017-07-12, 21:05:29
Bigguns, we cannot insert 0 as Curve subdivs. with 1, I have this strange white dots on every vertex.
I think it's a bug. also, you wrote to put "zero" to avoid the white dots. But.. in which option =) ?

And, I have discover that "Curves subdivs" works also with H&F =)

I meant, put zero in the glint, in the shader , by default the glint value is 0,2 , put 0 and it will be ok .
Title: Re: Hair shader playground and feedback
Post by: Bigguns on 2017-07-12, 21:44:46
some more old test ^^
Title: Re: Hair shader playground and feedback
Post by: cecofuli on 2017-07-12, 22:27:14
Bigguns, you have a PM =)
Title: Re: Hair shader playground and feedback
Post by: FrostKiwi on 2017-07-16, 10:51:29
(http://www.saires.de/anim.gif)
Did an animation of a furry teapot using H&F and found some corona buginess:
Animation as MP4 in attachment

Edit: screenshot in Attatchments of Corona massing Ram and never unlocking until crash.
Both DrSlave and Workstation produced a black frame once they ran out of all virtual memory.
Screenshot is after crash an hour before. Where it was 45 /45 GB virtual ram.
This is after ~8 frames. Each frame adds ~1.5gb ram that never unlock
Title: Re: Hair shader playground and feedback
Post by: Bigguns on 2017-07-16, 12:16:58
personnaly I did not tried it with hair and fur since I don't use it anymore.. it's so so bad.. but , you should not apply the material to the material slot in the hair and fur, it's for MR material. Just appy it to the emitter mesh , that's it. Also, in the environment ( never render the hairs as geo ! that shader is not made to work well on geo hairs! you'r loosing most of the quality of it by oding that and it takes more RAM ) I guess you should use buffer mode , but I'm not sure since I did not test it with hair and fur.
Title: Re: Hair shader playground and feedback
Post by: FrostKiwi on 2017-07-16, 12:24:15
personnaly I did not tried it with hair and fur since I don't use it anymore.. it's so so bad.. but , you should not apply the material to the material slot in the hair and fur, it's for MR material. Just appy it to the emitter mesh , that's it. Also, in the environment ( never render the hairs as geo ! that shader is not made to work well on geo hairs! you'r loosing most of the quality of it by oding that and it takes more RAM ) I guess you should use buffer mode , but I'm not sure since I did not test it with hair and fur.
Ohh snap! Thanks for the tipp. Gonna retry
Title: Re: Hair shader playground and feedback
Post by: Ondra on 2017-07-16, 22:59:15
corona actually uses the mr slot instead of emitter material
Title: Re: Hair shader playground and feedback
Post by: FrostKiwi on 2017-07-17, 13:44:40
corona actually uses the mr slot instead of emitter material
Yeah, I was about to say after I double checked with the Changelog.
I indeed had it set to geometry and that caused all the incorrect Ramlocking. With buffer mode it seems to.be all fine.

However, see picture attached. 2.5mio hair causes 500k rays/s, but transferring to mesh gives a boost to 800k rays/s (in normal scenes it is usually 2-2.5mio)
Is this subject to change, or will H&F buffer Hair always be slower than convert to mesh ? (Ignoring the horrible Ram explosion after mesh convert)
Also will parse times always be this aweful with H&F? For 2.5mio strands its almost a minute.
Title: Re: Hair shader playground and feedback
Post by: Ondra on 2017-07-17, 18:06:30
corona actually uses the mr slot instead of emitter material
Yeah, I was about to say after I double checked with the Changelog.
I indeed had it set to geometry and that caused all the incorrect Ramlocking. With buffer mode it seems to.be all fine.

However, see picture attached. 2.5mio hair causes 500k rays/s, but transferring to mesh gives a boost to 800k rays/s (in normal scenes it is usually 2-2.5mio)
Is this subject to change, or will H&F buffer Hair always be slower than convert to mesh ? (Ignoring the horrible Ram explosion after mesh convert)
Also will parse times always be this aweful with H&F? For 2.5mio strands its almost a minute.
do you use "render as planes" option? unchecking it slow things down pretty considerably. Generally usually hair is a bit slower to intersect, but way less memory hungry
Title: Re: Hair shader playground and feedback
Post by: FrostKiwi on 2017-07-17, 19:52:05
Quote from: Ondra link=topic=16730.msg105691#msg105691
do you use "render as planes" option?
Yeah, it is on by default. Was just suprised to find mesh faster than Hair & Fur Buffer.
Title: Re: Hair shader playground and feedback
Post by: Bigguns on 2017-07-18, 07:58:14
corona actually uses the mr slot instead of emitter material
Yeah, I was about to say after I double checked with the Changelog.
I indeed had it set to geometry and that caused all the incorrect Ramlocking. With buffer mode it seems to.be all fine.

However, see picture attached. 2.5mio hair causes 500k rays/s, but transferring to mesh gives a boost to 800k rays/s (in normal scenes it is usually 2-2.5mio)
Is this subject to change, or will H&F buffer Hair always be slower than convert to mesh ? (Ignoring the horrible Ram explosion after mesh convert)
Also will parse times always be this aweful with H&F? For 2.5mio strands its almost a minute.


Nice teapot haired ^^

2,5 millions of hairs.. less then a 1 min to parse.. not that slow to me. it's 2,5 millions ! give it a chance lol
Title: Re: Hair shader playground and feedback
Post by: Bigguns on 2017-07-18, 09:19:32
An other test

Title: Re: Hair shader playground and feedback
Post by: Fluss on 2017-07-18, 10:26:22
Hey guys,

I just want to react about the poll of this topic. No matter the outcome of the poll, I think that what matter the most is that all the shaders follows the same rules. Thus, if the coronamtl stick with glossiness input, then the Hair shader should behave the same way. Btw, from these two workflows, one of them seems to stand out as the standard today and it's the roughness one. I think YOU (devs) have to make that choice, not us (users), because i think (in most cases) you are responsible for making adopt these new workflows by imposing them. I think that's how a standard become a standard. I think it's really great to ask user feedback and this is one of the thing i love with corona development but on certain subjects like this one, I think we should not intervene.

Of course, this my point of view and i will understand some people will disagree with me. I just want to introduce some constructive discussion about that because it seems important to my eyes.

Title: Re: Hair shader playground and feedback
Post by: Bigguns on 2017-08-08, 20:05:38
Hi guy's , my latest hair tweak, added custom glint effects and hair breakdown into the reflection . Look's quite real now :P Lit with an hdri

Title: Re: Hair shader playground and feedback
Post by: Bigguns on 2017-08-17, 22:56:45
Converted my hairfarm daniel craig haircut to Ornatrix yesterday while learning ornatrix and rendered it with my latest set up of my corona hair shader .

Hope you like it ^^

Title: Re: Hair shader playground and feedback
Post by: Fluss on 2017-08-18, 09:27:10
Nice ! Still with custom glints ?
Title: Re: Hair shader playground and feedback
Post by: Bigguns on 2017-08-18, 20:44:41
yes and I have a new idea wich I think will improve it even more.. just need to test it ..
Title: Re: Hair shader playground and feedback
Post by: Bigguns on 2017-08-24, 12:03:34
Hi there, some more test . The haircut is from Tarkan Sarim , he sent me the splines and I transferred to ornatrix it was originally done in Xgen.

Hope you like it

(https://forum.corona-renderer.com/index.php?action=dlattach;topic=16730.0;attach=69513;image)
Title: Re: Hair shader playground and feedback
Post by: maru on 2017-08-24, 17:28:34
Is that He-Man or some lady from German olympics representation?
Title: Re: Hair shader playground and feedback
Post by: Bigguns on 2017-08-24, 21:55:58
lol it's not a lady for sure and I don't think it's he-man either lol he just did it for testing haircut in xgen I think
Title: Re: Hair shader playground and feedback
Post by: pokoy on 2017-08-24, 23:22:14
Great looking results! Many thanks for posting these and testing it extensively!
Title: Re: Hair shader playground and feedback
Post by: romullus on 2017-08-29, 11:44:16
Now when Corona Team has access to Chaos Group knoledge base, is there a chance that CoronaHair can be made fully functional with 3ds max H&F in the future?
Title: Re: Hair shader playground and feedback
Post by: Ondra on 2017-08-29, 11:54:18
Now when Corona Team has access to Chaos Group knoledge base, is there a chance that CoronaHair can be made fully functional with 3ds max H&F in the future?
which aspect of the 3dsmax h&f is not working? It now works in interactive, and we already consulted about the memory leak problem - we made it smaller, but there is a bug in 3dsmax implementation that makes it impossible for us not to leak at least some memory every time we render it.
Title: Re: Hair shader playground and feedback
Post by: romullus on 2017-08-29, 11:58:43
CoronaHair is not mappable in combination with H&F. Or should i say UV coordinates are not transfering from H&F to CoronaHair.
Title: Re: Hair shader playground and feedback
Post by: Ondra on 2017-08-29, 14:42:20
is it on mantis? I can explore that, but I think AD already said it is a known bug
Title: Re: Hair shader playground and feedback
Post by: romullus on 2017-08-29, 14:55:33
No, it's not on mantis yet. I'll create report later.

I remember when you've said it's autodesk's fault, i just thought that someone from Chaos may share a secret how they managed to make work V-ray with H&F :]

BTW, if it's autodesk bug, does that mean that it will work in later max versions? Maybe it's already working in max2017-18? Anyone can check that?
Title: Re: Hair shader playground and feedback
Post by: TomG on 2017-08-29, 20:27:36
I haven't found it to be working in 2017 with Corona hair mtl, though I am not that familiar with Max hair and fur yet so maybe I missed a setting someplace, will try to do some more testing and see!
Title: Re: Hair shader playground and feedback
Post by: maru on 2017-09-01, 11:47:50
One issue with Max H&F I am aware of is that the base object is not rendered. It's already logged in our internal task tracker.
Title: Re: Hair shader playground and feedback
Post by: romullus on 2017-09-01, 12:18:36
That's not always an issue, since hair guides usually are grown from low-poly version of base object and it has to be made non renderable anyway :]
Title: Re: 1.7 - Hair shader playground and feedback
Post by: cecofuli on 2017-09-09, 05:02:24
Someone can you explain me why, my Hair and Fur, change position from time to time? Loot at the roots
Nothing is animated.

(*) The spline (hair guides) are linked to the head and the head is linked to a dummy.
(*) The dummy has a simple 360° rotation.

Thanks



Title: Re: 1.7 - Hair shader playground and feedback
Post by: Alan on 2017-09-11, 15:17:45
Maybe if you detach the splines from the head. Use them just to recomb the guides and deform, after that detach from Spline Deform.
Title: Re: 1.7 - Hair shader playground and feedback
Post by: maru on 2017-09-14, 09:29:43
So, if someone here is using 3ds Max native hair and fur, would you rather have the base object visible or not?
The default behavior in Max is to have the base object visible, but there are also some arguments to have it hidden (e.g. you usually put hair on a lowpoly "cap" object).
Title: Quick Ornatrix test
Post by: thilima on 2017-09-14, 15:58:54
Quick test with ornatrix and Hair material
(https://i.imgur.com/87M9yda.jpg)
Title: Re: 1.7 - Hair shader playground and feedback
Post by: Juraj on 2017-09-14, 16:17:48
Damn it, I am glad I didn't open this thread at night time :- )
Title: Re: 1.7 - Hair shader playground and feedback
Post by: thilima on 2017-09-14, 16:59:25
Damn it, I am glad I didn't open this thread at night time :- )

auauauhauhauhuhauhauhahuauhauhauhuaha

Mission Accomplished :p
Title: Re: 1.7 - Hair shader playground and feedback
Post by: romullus on 2017-10-31, 18:58:46
Does Corona support hair object mapping along the strands? Not only roots and tips like in max's H&F, but proper mapping vith maps? Maybe with Ornatrix or Hairfarm it's possible?
Title: Re: 1.7 - Hair shader playground and feedback
Post by: maru on 2017-11-01, 09:55:27
Looks like it's working with Ornatrix and native hair and fur, at least with the gradient ramp. Let me know if that's not what you meant.
Title: Re: 1.7 - Hair shader playground and feedback
Post by: romullus on 2017-11-01, 10:07:09
Yes, that's exactly what i wanted. Great that it works with H&F too! Thanks maru!
Title: Re: 1.7 - Hair shader playground and feedback
Post by: Ondra on 2017-11-07, 16:02:48
all hair generators in corona create hair that are mapped in 0-1 interval in W dimension in all mapping channels