Corona Renderer Forum

Corona Renderer for 3ds Max => [Max] Daily Builds => Topic started by: GeorgeK on 2020-12-10, 18:05:19

Title: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2020-12-10, 18:05:19
From the latest Corona Renderer 7 Daily Builds Changelog:

Download Link: https://www.dropbox.com/s/7myibfgh9arlzqv/corona-7-3dsmax-daily-2020-12-10.exe?dl=0

(https://forum.corona-renderer.com/index.php?action=dlattach;topic=31802.0;attach=139211;image)

CoronaPhysicalMaterial is now available, please give it a try and share your feedback with us.

How it works:
Simply create a new material > Corona > CoronaPhysicalMtl, the older version of CoronaMtl is now labeled as CoronaLegacyMtl.
(https://forum.corona-renderer.com/index.php?action=dlattach;topic=31802.0;attach=139197;image)


CoronaPhysicalMtl consists of two modes-types that can be switched from the metalness rollout, Metal (conductor) and Non-metal (dielectric). Most of the basic parameters now change depending on the mode selected and the preferred material type. Various presets can be found in the material's basic options rollout.

(https://forum.corona-renderer.com/index.php?action=dlattach;topic=31802.0;attach=139454;image)

Since this is a physically based model, index or refraction-reflection is now limited to 3.0, reflection and refraction IOR are also connected into a single parameter (by default a highly refractive material, i.e. diamond will also have highly reflective surface if not rough). Metal materials don't use IOR for reflection intensity, rather their reflectance strength is based on color, roughness value or applied map, do note that roughness or glossiness model that can be interchanged from the Advanced options rollout of the CoronaPhysicalMtl itself.

(https://forum.corona-renderer.com/index.php?action=dlattach;topic=31802.0;attach=139201;image)

What else is new?
A ClearCoat layer is now included within the material, this can help coating your materials with a new layer that can have a different IOR reflection, separate bump, different roughness, and  absorption color. A great example of this is a PVC Plastic coated with a resin layer or other types of coats. Comparison of CoronaLegacyMtl with no coating and CoronaPhysicalMtl with coating: https://corona-renderer.com/comparer/FnPtXQ

(https://forum.corona-renderer.com/index.php?action=dlattach;topic=31802.0;attach=139203;image)

One more great addition is that of the Sheen layer which is responsible to represent an approximation of microfibers on cloth-surfaces like velvet or satin or other varying organic and rough surfaces. With a proper bump map it is now possible to emulate such cloth materials without the use of falloff, but by glossiness/roughness anisotropy and sheen layer alone.

(https://forum.corona-renderer.com/index.php?action=dlattach;topic=31802.0;attach=139205;image)

Lastly, there has been a rearrangement of various UI elements to be significantly more accessible to the user, best examples of this are the addition of Bump control in the Base layer section along with a better restructuring of parameters.

Is this it?
Anisotropic refraction is now a thing ;).

Corona Physical-material can be used along with CoronaLayeredMtl, a comparison between CoronaLegacyMtl and CoronaPhysicalMtl: https://corona-renderer.com/comparer/ZhR0A6

Coating on refractive spheres, a comparison between CoronaLegacyMtl and CoronaPhysicalMtl: https://corona-renderer.com/comparer/SSTif8


Credits for assets used in the tests (CC0 attribution license):
Butterfly, VirginiaTechUnivLibraries: https://sketchfab.com/3d-models/monarch-butterfly-3a5fc9a496cb402297ffdb6700d2ab60
HDRI: https://hdrihaven.com/hdri/?h=peppermint_powerplant
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Phasma on 2020-12-10, 20:20:36
this looks amazing!
Title: Re: New Corona Physical Material (PBR) playground!
Post by: scionik on 2020-12-10, 20:21:26
Just WOW. Let's play with it. Thank you!
Title: Re: New Corona Physical Material (PBR) playground!
Post by: juninholiveira on 2020-12-10, 20:43:53
Amazing! A question: The Corona Converter is already updated to convert to this new CoronaPhysicalMaterial? And what about the already existing Material Library? Any intentions to it?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: TomG on 2020-12-10, 20:48:52
The converter is not updated yet, because the material is not finalized (we are waiting on feedback from everyone to see if there needs to be further changes :) ). Can't start on the converter til the material is nicely locked and final, otherwise we'll just be re-writing the converter constantly ;)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: 88qba88 on 2020-12-10, 21:06:39
I've made some quick tests and I have a question about the visible brightness of new material.
Scene is made of 2 planes, 2 teapots and 2 spheres.
On part marked as NEW - new shader is applied, on part marked as OLD - Legacy Material is applied.

1 Corona Sun (size 1, value 1)
Environment - CoronaSky

Legacy Material settings:
Diffuse color: Corona Color R:180 G:180 B:180
Reflection: 1,0
Glossiness: Corona Color R:80 G:80 B:80

NEW: (same as above, switched from roughness to glossiness)
Mat settings:
Base Color: Corona Color R:180 G:180 B:180
Reflection: 1,0
Glossiness: Corona Color R:80 G:80 B:80
Non-metal

I can see that part with new material changes brightness quite hard depending on viewing angle. I believe the plane should be brighter when viewed towards the sun and darker in opposite direction?

Another issue seems to be visible when the camera is perpendicular to sun - I can see some changes in visible brightness of the plane from left to right.

Is that correct behavior?

Thanks
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Juraj on 2020-12-10, 21:17:57
Nice :- )
Title: Re: New Corona Physical Material (PBR) playground!
Post by: lupaz on 2020-12-10, 21:21:58
Exciting!!!
Could anyone post a screenshot of the material UI in the material editor please?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2020-12-10, 21:32:31
@lupaz

(https://i.imgur.com/r93Ltb3.png)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2020-12-10, 21:36:03
So if we have to specify metalness (metal or non-metal) at the top of the material, which do you choose if both metal and non-metal surfaces are represented in a single texture set?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Mohammadreza Mohseni on 2020-12-10, 22:27:39
I am gonna have so much fun to test this daily build.

Title: Re: New Corona Physical Material (PBR) playground!
Post by: romullus on 2020-12-10, 23:32:57
So if we have to specify metalness (metal or non-metal) at the top of the material, which do you choose if both metal and non-metal surfaces are represented in a single texture set?

You should use layered material then. Same as with legacy material.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: bluebox on 2020-12-10, 23:46:34
Am I correct to say that you guys implemented oren-nayar diffuse model ? This looks really really promissing !
Title: Re: New Corona Physical Material (PBR) playground!
Post by: TomG on 2020-12-11, 00:55:08
So if we have to specify metalness (metal or non-metal) at the top of the material, which do you choose if both metal and non-metal surfaces are represented in a single texture set?

There's a map slot for metalness, if you want a material to vary metal to non-metal over the surface.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2020-12-11, 01:00:21
So if we have to specify metalness (metal or non-metal) at the top of the material, which do you choose if both metal and non-metal surfaces are represented in a single texture set?

There's a map slot for metalness, if you want a material to vary metal to non-metal over the surface.

Nice, so between your response and Romullus' it sounds like the functionality from the Legacy Material is preserved.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: agentdark45 on 2020-12-11, 02:14:11
Am I correct to say that you guys implemented oren-nayar diffuse model ? This looks really really promissing !

Would like to know more about this for sure. The Arnold examples posted a while ago really benefited from the diffuse model.

Also, is there a guide for how to use legacy reflection and glossyness maps with the new PBR material?

Also, under what circumstances would you use the metalness/non-metal workflow? For example; semi-polished concrete, dark antique/tarnished bronze, polished marble, silk rugs, car paint e.t.c. I'm a bit confused as to where the cut off point is where materials have a reflective but also strong diffuse component. Or am I misunderstanding metalness?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2020-12-11, 06:19:21
I don't think there is such a thing as 'legacy reflection and glossyness maps' in the context of the physical material(?)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Ondra on 2020-12-11, 08:12:27
So if we have to specify metalness (metal or non-metal) at the top of the material, which do you choose if both metal and non-metal surfaces are represented in a single texture set?

In that case you will set a metalness map, and the dropdown will become greyed out, signalling that it is no longer used. Both options for metal and non-metal material become unlocked.

Title: Re: New Corona Physical Material (PBR) playground!
Post by: Ondra on 2020-12-11, 08:15:39
Also, under what circumstances would you use the metalness/non-metal workflow? For example; semi-polished concrete, dark antique/tarnished bronze, polished marble, silk rugs, car paint e.t.c. I'm a bit confused as to where the cut off point is where materials have a reflective but also strong diffuse component. Or am I misunderstanding metalness?

metalness should be really used only for materials made of metal - so concrete, marble, silk are non-metal. Darkened bronze would be probably done with metalness map (metal bronze vs. non-metal "dirt"). Car paint is very complex and specific material, neither metal nor non-metal will represent it 100% physically, so I guess it would be possible to fake it with both
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Bormax on 2020-12-11, 08:33:58
New material is really great! Thank you!

The Clearcoat layer is the thing I was missing for very long time, nice to get it now. Some idea came to my mind about it.
Now the Base bump affects the Clearcoat layer and Clearcoat bump gives possibility to Add bump to this layer. Would it be nice (if it's possible) to have kinda lock between Base bump and Clearcoat bump in order to imitate the bumpy surface covered by the polished transparent layer of lacquer? Something like on attached picture where I've created the geometry of the covering layer and assigned different material to the inner and covering surfaces.
According to this idea if the Lock is active Base bump affects the Coatlayer, if it's unlocked only Clearcoat layer's bump affects the Coat layer.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2020-12-11, 08:34:57
I've made some quick tests and I have a question about the visible brightness of new material.
Scene is made of 2 planes, 2 teapots and 2 spheres.
On part marked as NEW - new shader is applied, on part marked as OLD - Legacy Material is applied.

1 Corona Sun (size 1, value 1)
Environment - CoronaSky

Legacy Material settings:
Diffuse color: Corona Color R:180 G:180 B:180
Reflection: 1,0
Glossiness: Corona Color R:80 G:80 B:80

NEW: (same as above, switched from roughness to glossiness)
Mat settings:
Base Color: Corona Color R:180 G:180 B:180
Reflection: 1,0
Glossiness: Corona Color R:80 G:80 B:80
Non-metal

I can see that part with new material changes brightness quite hard depending on viewing angle. I believe the plane should be brighter when viewed towards the sun and darker in opposite direction?

Another issue seems to be visible when the camera is perpendicular to sun - I can see some changes in visible brightness of the plane from left to right.

Is that correct behavior?

Thanks

That is indeed expected as the new diffuse model is somewhat retro-reflective at low glossiness.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: 88qba88 on 2020-12-11, 08:45:12
I've made some quick tests and I have a question about the visible brightness of new material.
Scene is made of 2 planes, 2 teapots and 2 spheres.
On part marked as NEW - new shader is applied, on part marked as OLD - Legacy Material is applied.

1 Corona Sun (size 1, value 1)
Environment - CoronaSky

Legacy Material settings:
Diffuse color: Corona Color R:180 G:180 B:180
Reflection: 1,0
Glossiness: Corona Color R:80 G:80 B:80

NEW: (same as above, switched from roughness to glossiness)
Mat settings:
Base Color: Corona Color R:180 G:180 B:180
Reflection: 1,0
Glossiness: Corona Color R:80 G:80 B:80
Non-metal

I can see that part with new material changes brightness quite hard depending on viewing angle. I believe the plane should be brighter when viewed towards the sun and darker in opposite direction?

Another issue seems to be visible when the camera is perpendicular to sun - I can see some changes in visible brightness of the plane from left to right.

Is that correct behavior?

Thanks

That is indeed expected as the new diffuse model is somewhat retro-reflective at low glossiness.

Thank you for the answer:)
It doesn't look like a huge problem, especially considering photorealistic renderings, but when you start creating for example packshot images or renderings with lots of flat surfaces it looks a little bit like there is some smoothing groups problem in 3ds max!
By the way - I really like the new shader with all its possibilities! I like the UI and workflow changes that comes with it.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marti_d on 2020-12-11, 12:23:02
Hello everyone, just a simple question. When working with the new material where is one supposed to plug in the Reflection Glossiness map the old material used?
Tried different methods but didn't seem to work the same way.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2020-12-11, 13:04:16
Hello everyone, just a simple question. When working with the new material where is one supposed to plug in the Reflection Glossiness map the old material used?
Tried different methods but didn't seem to work the same way.

That would be your base roughness or base glossiness slot, but keep in mind that you have to invert the values of your glossiness map if you are using roughness. Alternatively, you can change the mode by going to your CoronaPhysicalMtl > Advanced Options and change the Roughness mode to Glossiness.

You should get the same glossiness between CMTL and PBR, if you plug the reflection glossiness map to Base glossiness for PBR, do note that your PBR result will be slightly brighter, even with the same IOR.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: agentdark45 on 2020-12-11, 13:39:51
metalness should be really used only for materials made of metal - so concrete, marble, silk are non-metal. Darkened bronze would be probably done with metalness map (metal bronze vs. non-metal "dirt"). Car paint is very complex and specific material, neither metal nor non-metal will represent it 100% physically, so I guess it would be possible to fake it with both

Great, thanks for clearing that up.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marti_d on 2020-12-11, 14:07:01
Hello everyone, just a simple question. When working with the new material where is one supposed to plug in the Reflection Glossiness map the old material used?
Tried different methods but didn't seem to work the same way.

That would be your base roughness or base glossiness slot, but keep in mind that you have to invert the values of your glossiness map if you are using roughness. Alternatively, you can change the mode by going to your CoronaPhysicalMtl > Advanced Options and change the Roughness mode to Glossiness.

You should get the same glossiness between CMTL and PBR, if you plug the reflection glossiness map to Base glossiness for PBR, do note that your PBR result will be slightly brighter, even with the same IOR.

Hello, I tried just that but I am not getting the same result. Is this how it should look like?This is the reflection pass. Old has the map plugged in the reflection glossines the new one has in the base glossiness.
Also in the translucency tab there is no more translucency fraction should we control the amount with the map only now ?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2020-12-11, 16:05:07
Hello everyone, just a simple question. When working with the new material where is one supposed to plug in the Reflection Glossiness map the old material used?
Tried different methods but didn't seem to work the same way.

That would be your base roughness or base glossiness slot, but keep in mind that you have to invert the values of your glossiness map if you are using roughness. Alternatively, you can change the mode by going to your CoronaPhysicalMtl > Advanced Options and change the Roughness mode to Glossiness.

You should get the same glossiness between CMTL and PBR, if you plug the reflection glossiness map to Base glossiness for PBR, do note that your PBR result will be slightly brighter, even with the same IOR.

Hello, I tried just that but I am not getting the same result. Is this how it should look like?This is the reflection pass. Old has the map plugged in the reflection glossines the new one has in the base glossiness.
Also in the translucency tab there is no more translucency fraction should we control the amount with the map only now ?

We will look into this further, as there might be cases where this is an issue.

In regards to your second question, the translucency fraction is still there labeled as "Translucency" you can enable it and use it without the use of a map simply by enabling the Thin Shell (no inside) option above Base Layer. The color of the translucency depends on your base layer color.

Thank you.

(Report ID=CRMAX-71)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marti_d on 2020-12-11, 16:53:41
Hello everyone, just a simple question. When working with the new material where is one supposed to plug in the Reflection Glossiness map the old material used?
Tried different methods but didn't seem to work the same way.

That would be your base roughness or base glossiness slot, but keep in mind that you have to invert the values of your glossiness map if you are using roughness. Alternatively, you can change the mode by going to your CoronaPhysicalMtl > Advanced Options and change the Roughness mode to Glossiness.

You should get the same glossiness between CMTL and PBR, if you plug the reflection glossiness map to Base glossiness for PBR, do note that your PBR result will be slightly brighter, even with the same IOR.

Hello, I tried just that but I am not getting the same result. Is this how it should look like?This is the reflection pass. Old has the map plugged in the reflection glossines the new one has in the base glossiness.
Also in the translucency tab there is no more translucency fraction should we control the amount with the map only now ?

We will look into this further, as there might be cases where this is an issue.

In regards to your second question, the translucency fraction is still there labeled as "Translucency" you can enable it and use it without the use of a map simply by enabling the Thin Shell (no inside) option above Base Layer. The color of the translucency depends on your base layer color.

Thank you.

(Report ID=CRMAX-71)

Yes but before after you plugged in a map you could still control the amount of translucency with the fraction now you can't. You have just the map and that's it.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marchik on 2020-12-11, 18:56:58
New material is really great! Thank you!

The Clearcoat layer is the thing I was missing for very long time, nice to get it now. Some idea came to my mind about it.
Now the Base bump affects the Clearcoat layer and Clearcoat bump gives possibility to Add bump to this layer. Would it be nice (if it's possible) to have kinda lock between Base bump and Clearcoat bump in order to imitate the bumpy surface covered by the polished transparent layer of lacquer? Something like on attached picture where I've created the geometry of the covering layer and assigned different material to the inner and covering surfaces.
According to this idea if the Lock is active Base bump affects the Coatlayer, if it's unlocked only Clearcoat layer's bump affects the Coat layer.
+
yes, current implementation of bumps interaction is a little bit strange :D

I think you can focus on the implementation as in the standard physical material with "affect underying" concepts
One more great addition is that of the Sheen layer which is responsible to represent an approximation of microfibers on cloth-surfaces like velvet or satin or other varying organic and rough surfaces. With a proper bump map it is now possible to emulate such cloth materials without the use of falloff, but by glossiness/roughness anisotropy and sheen layer alone.
As for fabrics and sheen, if possible I would like to see an example of a photorealistic silk or velvet/crushed velvet shaders using as said detailed bump maps, for example these
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Kyle on 2020-12-12, 11:13:26
As far as I can tell the Substance Painter to 3ds Max workflow is working very well.  Just found an old model I made from a Blender tutorial slapped some smart materials on in Substance Painter, exported Albedo, Metalness, Roughness, Normal and Height maps.  Just slotted them into the new material and all seems to work as expected.  Took about 10 mins to do all together. Great work on the new material Corona team!
Title: Re: New Corona Physical Material (PBR) playground!
Post by: joonior1985 on 2020-12-12, 17:38:06
Hey there,
is there a difference between sheen parameter and regular falloff mask? Same question could be applied to a potential difference between using new clearcoat option and regular CoronaLayeredMtl where clearcoat is a regular glossy material masked with base layer using fresnel. I'm just curious because for instance velvet material is a pain in the ass as it's way more complex than just falloff and/or "sheen" :)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Feodor on 2020-12-12, 18:24:56
As always, you are on top!

But!
When testing the new Shader, I found two problems.
First: in a refractive material, when the minimum roughness value is set, the IOR changes significantly. Shown in the picture. Especially the picture becomes different when using glass with the Shell modifier
Second: if you set the roughness value to 0 in the Sheen layer, 3ds max 2021 will hang dead. (There must be a division by zero) :))
Title: Re: New Corona Physical Material (PBR) playground!
Post by: pokoy on 2020-12-12, 22:56:57
As always, you are on top!

But!
When testing the new Shader, I found two problems.
First: in a refractive material, when the minimum roughness value is set, the IOR changes significantly. Shown in the picture. Especially the picture becomes different when using glass with the Shell modifier
Second: if you set the roughness value to 0 in the Sheen layer, 3ds max 2021 will hang dead. (There must be a division by zero) :))
I think the same happened with the old material, too. Could you test this to verify?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Feodor on 2020-12-13, 11:28:46
Yes, the old material has the same problem. It is worth changing the roughness value in the reflection, how much does the IOR change in refraction, but how do I understand this applies only to the background?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Juraj on 2020-12-13, 14:44:12
Hey there,
is there a difference between sheen parameter and regular falloff mask? Same question could be applied to a potential difference between using new clearcoat option and regular CoronaLayeredMtl where clearcoat is a regular glossy material masked with base layer using fresnel. I'm just curious because for instance velvet material is a pain in the ass as it's way more complex than just falloff and/or "sheen" :)

From my testing, esp. Sheen doesn't seem to act much differently than Fallof, although it automatizes the setup with simpler setup ("Roughness"). I didn't test it too extensively but doesn't seem like it reacts to light or anything of that sort.

The best velvet setup is still mystery to me :- ).
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Feodor on 2020-12-13, 17:19:39


From my testing, esp. Sheen doesn't seem to act much differently than Fallof, although it automatizes the setup with simpler setup ("Roughness"). I didn't test it too extensively but doesn't seem like it reacts to light or anything of that sort.

The best velvet setup is still mystery to me :- ).

I don't think it's just Fallof

Title: Re: New Corona Physical Material (PBR) playground!
Post by: joonior1985 on 2020-12-13, 18:57:05

From my testing, esp. Sheen doesn't seem to act much differently than Fallof, although it automatizes the setup with simpler setup ("Roughness"). I didn't test it too extensively but doesn't seem like it reacts to light or anything of that sort.

The best velvet setup is still mystery to me :- ).

Apparently it really does work differently. Regular Fallof doesn't take light source directional vector into account but sheen does. Check out my previews :)
P.S. I figured out (partially) a relatively good velvet shader but still it's not the general solution that works in every scenario :D
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Epilog studio on 2020-12-13, 19:57:37
Hello, The overall concept of new material is looking great But I am missing one big feature- ability to define BRDF more precisely. Is it planned? Tail fallof etc?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Juraj on 2020-12-14, 08:21:39

From my testing, esp. Sheen doesn't seem to act much differently than Fallof, although it automatizes the setup with simpler setup ("Roughness"). I didn't test it too extensively but doesn't seem like it reacts to light or anything of that sort.

The best velvet setup is still mystery to me :- ).

Apparently it really does work differently. Regular Fallof doesn't take light source directional vector into account but sheen does. Check out my previews :)
P.S. I figured out (partially) a relatively good velvet shader but still it's not the general solution that works in every scenario :D

I downloaded this into Photoshop but I am still not sure what I am looking at :- ) The light spread the sheen "specular" lobes? The lobes react do directionality/size of light?

Title: Re: New Corona Physical Material (PBR) playground!
Post by: rowmanns on 2020-12-14, 09:35:38
As always, you are on top!

But!
When testing the new Shader, I found two problems.
First: in a refractive material, when the minimum roughness value is set, the IOR changes significantly. Shown in the picture. Especially the picture becomes different when using glass with the Shell modifier
Second: if you set the roughness value to 0 in the Sheen layer, 3ds max 2021 will hang dead. (There must be a division by zero) :))

Hi,

Can you send over a scene for the second issue you described? I am unable to reproduce this crash/hang.

Cheers,

Rowan
Title: Re: New Corona Physical Material (PBR) playground!
Post by: mvshabeer on 2020-12-14, 09:44:08
This is not specifically to PBR material. Here is the comparison b/n default max physical material and Corona physical material.
It will be nice to have viewport preview (reflections) in high quality mode. Latest max  even supports bloom. For those who argue about the use case, some projects we don't even render due to time restrictions and last minute changes. We use viewport previews. So far we have been creating 2 scene files, one with max physical material setup for previews and one with corona for rendering if needed. It will be really helpful if Corona have an option of high quality preview in viewports

Title: Re: New Corona Physical Material (PBR) playground!
Post by: joonior1985 on 2020-12-14, 09:47:49

From my testing, esp. Sheen doesn't seem to act much differently than Fallof, although it automatizes the setup with simpler setup ("Roughness"). I didn't test it too extensively but doesn't seem like it reacts to light or anything of that sort.

The best velvet setup is still mystery to me :- ).

Apparently it really does work differently. Regular Falloff doesn't take light source directional vector into account but sheen does. Check out my previews :)
P.S. I figured out (partially) a relatively good velvet shader but still it's not the general solution that works in every scenario :D

I downloaded this into Photoshop but I am still not sure what I am looking at :- ) The light spread the sheen "specular" lobes? The lobes react do directionality/size of light?

I prepared more obvious sample that explains how it works :) The Sheen somehow reacts with count of the light sources and their direction creating this radial gradient instead of linear (when using regular falloff). I still got no clue if there is any groundbreaking advantage over well customized falloff but I'll do some more testing anyway. It may works with satin materials but velvet from my adventures with that particular material is (as said in previous post) more complex. Velvet must take into account few variables (third is most important):
1. Falloff/Sheen (done)
2. Specular with anisotropy (done)
3. Handling a 3D map/bitmap that allows to recognize what particular direction and angle the surface is to the light and camera. The real physical velvet piece (lets say a square 50x50 cm) looks different for every angle. It is caused by tiny hairs that leans always to a particular direction (in world coordinates) and once they lean towards You but if You rotate this piece of fabric they don't change their direction according to surface but they do so for the viewer/camera. Thats the basic principle that (from my knowledge) nobody handled yet :D
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Juraj on 2020-12-14, 11:15:40
I wonder if what you are showing isn't just the diffuse retro-reflection very rough materials now have from Oren-Nayar shading. Is there a sheen pass to check? I would check the diffuse pass to see.

Fabric effect is extremely convincing from GeoPattern feature but sampling from normal maps not much so yet.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2020-12-14, 11:58:08
As for fabrics and sheen, if possible I would like to see an example of a photorealistic silk or velvet/crushed velvet shaders using as said detailed bump maps, for example these

Satin is a bit tough to work on bump+sheen alone, it is somewhat reproducible but the lack of detailed maps, proper UVs won't make it look nice in most angles, so you'll have to resort to using a custom fresnel.

Thus you can apply a falloff curve to sheen itself in order to emulate more satin surfaces, this works great and the effect is more subtle than diffuse+falloff and seems to react better with scene lighting overall.
(https://forum.corona-renderer.com/index.php?action=dlattach;topic=31802.0;attach=139462;image)

For silk-velvet, sheen alone is enough, comparison: https://corona-renderer.com/comparer/RugNph
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marchik on 2020-12-14, 12:58:30

Satin is a bit tough to work on bump+sheen alone, it is somewhat reproducible but the lack of detailed maps, proper UVs won't make it look nice in most angles, so you'll have to resort to using a custom fresnel.

Thus you can apply a falloff curve to sheen itself in order to emulate more satin surfaces, this works great and the effect is more subtle than diffuse+falloff and seems to react better with scene lighting overall.


For silk-velvet, sheen alone is enough, comparison: https://corona-renderer.com/comparer/RugNph
Thx for the reply, I mainly work with fabrics and have made hundreds of attempts to recreate complex shaders such as velvet, satin, silk, wool  and so on, including growing millions of fibers in Ornatrix and combing them and then using CoronaHairMtl  to get proper anisotropy reflection for the correct velvet, and basically I can create any texture in substance designer e.g.

But at the moment, if I understand everything correctly, we have no way to get the correct direction of the anisotropic reflection along the single fabric thread using height maps or normal maps, no matter how detailed they are, we can only fake it using the anisotropy rotation map.

And we also don't have a geopattern to mimic the real fabric structure. So I'll probably have to tweak the faloffs again and wait for the next release :D

PS
please guys, pay attention to the implementation of coating, which we wrote about above. let it be possible for coating to smooth the surface, creating mirror-like glossy coat with displaying the height details of the surface lying below, as Bormax mentioned here
New material is really great! Thank you!

The Clearcoat layer is the thing I was missing for very long time, nice to get it now. Some idea came to my mind about it.
Now the Base bump affects the Clearcoat layer and Clearcoat bump gives possibility to Add bump to this layer. Would it be nice (if it's possible) to have kinda lock between Base bump and Clearcoat bump in order to imitate the bumpy surface covered by the polished transparent layer of lacquer? Something like on attached picture where I've created the geometry of the covering layer and assigned different material to the inner and covering surfaces.
According to this idea if the Lock is active Base bump affects the Coatlayer, if it's unlocked only Clearcoat layer's bump affects the Coat layer.

PPS
and maybe it is worth lowering the metalness map slot below the others, because now I habitually attach base color or diffuse to it as it is the first in the list :D
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Feodor on 2020-12-14, 15:28:19

Hi,

Can you send over a scene for the second issue you described? I am unable to reproduce this crash/hang.

Cheers,

Rowan

It doesn't make sense to load the scene at all. Try creating a teapot object, with 64 segments, or a sphere of 200 segments, put the material and click the render button. This happens with highly polygonal objects
Title: Re: New Corona Physical Material (PBR) playground!
Post by: rowmanns on 2020-12-14, 16:08:03

Hi,

Can you send over a scene for the second issue you described? I am unable to reproduce this crash/hang.

Cheers,

Rowan
It doesn't make sense to load the scene at all. Try creating a teapot object, with 64 segments, or a sphere of 200 segments, put the material and click the render button. This happens with highly polygonal objects
Hey,

Thanks for the info! I was missing the high polygon objects part. I will forward this to our devs.

Rowan

(Report ID=CRMAX-80)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2020-12-15, 09:20:36
PS
please guys, pay attention to the implementation of coating, which we wrote about above. let it be possible for coating to smooth the surface, creating mirror-like glossy coat with displaying the height details of the surface lying below, as Bormax mentioned here
New material is really great! Thank you!

The Clearcoat layer is the thing I was missing for very long time, nice to get it now. Some idea came to my mind about it.
Now the Base bump affects the Clearcoat layer and Clearcoat bump gives possibility to Add bump to this layer. Would it be nice (if it's possible) to have kinda lock between Base bump and Clearcoat bump in order to imitate the bumpy surface covered by the polished transparent layer of lacquer? Something like on attached picture where I've created the geometry of the covering layer and assigned different material to the inner and covering surfaces.
According to this idea if the Lock is active Base bump affects the Coatlayer, if it's unlocked only Clearcoat layer's bump affects the Coat layer.

PPS
and maybe it is worth lowering the metalness map slot below the others, because now I habitually attach base color or diffuse to it as it is the first in the list :D

Thank you and Bormax for your input on this, I have passed all information to the devs.

(Report ID=CRMAX-85)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: n2graf on 2020-12-17, 23:38:52
I have seen that you have improved the BDRF single scattering problem that appears for maximum reflections with high roughtness, where all the 100x100 light should be reflected. Now it reflects much more light than before. Will it end up implementing a multiple scattering BDRF solution where all complete 100x100 of the light is reflected?

It would be nice if there was a numerical value for the amount of metalness because almost no material in reality is pure metal, there is always a film of rust or dust, and we would save time applying a corona color to obtain a gray value, if we could regulate the amount of metalness with a numerical value as an alternative to using a map.


Thanks!
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2020-12-18, 12:58:57
I have seen that you have improved the BDRF single scattering problem that appears for maximum reflections with high roughtness, where all the 100x100 light should be reflected. Now it reflects much more light than before. Will it end up implementing a multiple scattering BDRF solution where all complete 100x100 of the light is reflected?

It would be nice if there was a numerical value for the amount of metalness because almost no material in reality is pure metal, there is always a film of rust or dust, and we would save time applying a corona color to obtain a gray value, if we could regulate the amount of metalness with a numerical value as an alternative to using a map.


Thanks!

Hey, thanks for the feedback. I will get back to you on the first one, in regards to the second I have reported it to the dev-team for consideration.

(report id=CRMAX-120)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marchik on 2020-12-22, 05:12:43
for some reason I now miss the opportunity to change the final level of reflections using a spinner or a BW map, sometimes it helps a lot in bringing the floor material to realism, now you have to create a composite map with two ior values :DDD
Title: Re: New Corona Physical Material (PBR) playground!
Post by: maru on 2020-12-22, 12:19:26
for some reason I now miss the opportunity to change the final level of reflections using a spinner or a BW map, sometimes it helps a lot in bringing the floor material to realism, now you have to create a composite map with two ior values :DDD

Can you explain what exact property you would like to change?
With the new physical material, you should be following the metalness/roughness workflow. You can map metalness, roughness, and IOR.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marchik on 2020-12-24, 05:06:05
for some reason I now miss the opportunity to change the final level of reflections using a spinner or a BW map, sometimes it helps a lot in bringing the floor material to realism, now you have to create a composite map with two ior values :DDD

Can you explain what exact property you would like to change?
With the new physical material, you should be following the metalness/roughness workflow. You can map metalness, roughness, and IOR.

Of course I understand that I should use a metallic / roughness workflow, there is no problem with that) and of course there is a direct relationship between roughness and the strength of reflections, the same as it was in legacy corona mtl

And despite this, there are some materials in which, to achieve better results, sometimes it is necessary to tweak the final strength of the reflections with spinner or B&W map, and its not very convenient to do this by mixing two linear ior values

as an example, lets take a flooring material, let's assume I use a generator from Poliigon and at the output, in addition to roughness, I will also get a specular level (pic1) but unfortunately now I can't use it directly but only as a mask when mixing two IORs, in fact it is not a big problem, except that mixing different IORs give a slightly different result from simply reducing the strength of reflections. e.g. in legacy mtl i used speclvl in reflection color slot with about 5-15% of opacity
Title: Re: New Corona Physical Material (PBR) playground!
Post by: romullus on 2020-12-24, 14:16:40
as an example, lets take a flooring material, let's assume I use a generator from Poliigon and at the output, in addition to roughness, I will also get a specular level (pic1) but unfortunately now I can't use it directly but only as a mask when mixing two IORs, in fact it is not a big problem, except that mixing different IORs give a slightly different result from simply reducing the strength of reflections. e.g. in legacy mtl i used speclvl in reflection color slot with about 5-15% of opacity

I can't tell you how realistic those maps are - i suspect they are pretty arbitrary, but by mapping IOR instead of reflection level, you get at least physically more correct results, even if it requires more work to set-up.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marchik on 2020-12-25, 02:29:04

I can't tell you how realistic those maps are - i suspect they are pretty arbitrary, but by mapping IOR instead of reflection level, you get at least physically more correct results, even if it requires more work to set-up.
exactly) no matter how realistic those maps are, my eye and little tweaks will make them look realistic)
and for my part, I'm just looking for a handy tool that will allow me to achieve this in less amount of time.

it would probably be a good idea to allow  mapping ior values ​​with rgb where  ​​1.0 is 0.0.0 and 3.0 is 255.255.255, in this case we can easily clamp our speclvl map values ​​to 0-128 and get reasonable results. Just my thoughts.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: n2graf on 2021-01-07, 14:48:13
I wanted to contribute some insights.

For metallic materials that accumulate a thin layer of dust, it is interesting to be able to map the metalness so that it has dielectric zones (non-metal), as the physicalmtl now allows. Previously we could do this by lowering the reflection and the diffuse color would appear. The problem now is that you are forced to make the reflection color the same as the diffuse color of the non-metal you are mixing, since there is only one slot for base color. It might be interesting that there is a slot for diffuse so you can separate the gold color for the reflection of the metal and the white color for the diffuse of the layer of dust or dirt. I know that it can usually be solved with the coronalayeredmtl but it is more laborious and makes sense for more complex cases. When you only want to add dust and dirt it would be useful to be able to do it from the physicalmtl itself since it has the option to map the metalness. Another option would be to place an identical color texture to the one we placed in metalness but that has the desired colors for the metal area and for the diffuse area of ​​dirt, but it is difficult to achieve textures like this or they would have to be generated by adding shaders previously, which complicates work, for this reason I think the most practical would be a slot for diffuse that will be activated only in the case that you want to map the metalness, as well as a spinner in metalness would be practical to be able to mix it numerically for little complex cases where we can save the step of putting a map. Thank you!
Title: Re: New Corona Physical Material (PBR) playground!
Post by: maru on 2021-01-08, 10:33:14
it would probably be a good idea to allow  mapping ior values ​​with rgb where  ​​1.0 is 0.0.0 and 3.0 is 255.255.255, in this case we can easily clamp our speclvl map values ​​to 0-128 and get reasonable results. Just my thoughts.

Is this (screenshot attached) solution good enough for you, or would it be vital to have some kind of native Corona feature for this?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: maru on 2021-01-08, 10:37:37
For metallic materials that accumulate a thin layer of dust...

The issue is that metal and dust are two completely different materials. Layered Mtl would be definitely preferred here.
Maybe you could also use the built in Sheen layer? (you can specify its color, amount, and roughness so it's a bit like a layer of non-metal).
Title: Re: New Corona Physical Material (PBR) playground!
Post by: rowmanns on 2021-01-08, 19:51:09
As always, you are on top!

But!
When testing the new Shader, I found two problems.
First: in a refractive material, when the minimum roughness value is set, the IOR changes significantly. Shown in the picture. Especially the picture becomes different when using glass with the Shell modifier
Second: if you set the roughness value to 0 in the Sheen layer, 3ds max 2021 will hang dead. (There must be a division by zero) :))
Second issue is fixed in the latest daily. Available here: https://forum.corona-renderer.com/index.php?topic=30876.msg180340#msg180340

Cheers.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marchik on 2021-01-09, 01:32:37
it would probably be a good idea to allow  mapping ior values ​​with rgb where  ​​1.0 is 0.0.0 and 3.0 is 255.255.255, in this case we can easily clamp our speclvl map values ​​to 0-128 and get reasonable results. Just my thoughts.

Is this (screenshot attached) solution good enough for you, or would it be vital to have some kind of native Corona feature for this?
As I described, I am using this solution now, of course, this is not an "vital" feature, but just my suggestion to simplify the usage of the new shader, is that what you are aiming for in the end? convenience and realism) What I'm most worried about right now is the implementation of changing the bump effect on the clearcoat layer. Everything except the clearcoat layer works well overall, thx :D
Title: Re: New Corona Physical Material (PBR) playground!
Post by: pokoy on 2021-01-09, 08:59:33
it would probably be a good idea to allow  mapping ior values ​​with rgb where  ​​1.0 is 0.0.0 and 3.0 is 255.255.255, in this case we can easily clamp our speclvl map values ​​to 0-128 and get reasonable results. Just my thoughts.

Is this (screenshot attached) solution good enough for you, or would it be vital to have some kind of native Corona feature for this?

I've said it many times and always will - this setup is so cumbersome it hurts. Thinking this is good enough is a mistake, sorry.
You should map incoming images so that RGB 0 is IOR 1.0 and RGB 255 is the specified IOR in the material UI. Or make a new IOR map where users can specify the value mapping in a similar way.
But to me, your setup is just not sufficient in terms of use ease nor setup time, plus you can't see what the values specified are unless you inspect all nested maps, that's absolutely insane.
It looks like you guys are going the Autodesk way on this one - "half-assed will do it, let's not think any further."
I don't mean to offend, but we already discussed this elsewhere and it's frustrating you think it's good enough.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: romullus on 2021-01-09, 12:08:36
It doesn't have to be cumbersome, just set-up this map once, save it to a material library and never get bothered by creating it again. And you can control everything from slate editor view, no need to go to parameter editor.

I think you are well aware that remapping Corona IOR slot as you ask, would break other people's workflows and your suggestion to introduce new IOR map would go directly against Corona's policy about simplicity. I think that current solution is more flexible and it's not complicated at all to anyone who's using slate material editor.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: agentdark45 on 2021-01-09, 21:37:41
Would it not be easier to just create a dedicated "IOR map" that the source bitmap feeds into, that automatically inverts, and internally changes the high value according to whatever the main material IOR is? This implementation shouldn't need a material rewrite or break any pre-existing material setups (kind of like how a bitmap feeds into a "normal map" before going into the bump slot).
Title: Re: New Corona Physical Material (PBR) playground!
Post by: pokoy on 2021-01-09, 22:57:51
It doesn't have to be cumbersome, just set-up this map once, save it to a material library and never get bothered by creating it again. And you can control everything from slate editor view, no need to go to parameter editor.

I think you are well aware that remapping Corona IOR slot as you ask, would break other people's workflows and your suggestion to introduce new IOR map would go directly against Corona's policy about simplicity. I think that current solution is more flexible and it's not complicated at all to anyone who's using slate material editor.
If you work on projects with some pressure behind or have to inspect existing materials and need  the fastest visual feedback you can get, going into submaps to figure out values is the last thing you need. The new workflow is flawed.
We can agree to disagree.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Juraj on 2021-01-10, 10:21:44
I've placed the above macro that Romullus wrote into my base Corona material in Editor and inactivated it (checkbox off). I did this since day one.

Yes it's effectively what Pokoy writes could be called 'IOR map' but I am ok with this solution which is how FresnelIOR map should have always been (Since no one really uses it because of how cumbersome it is).
Title: Re: New Corona Physical Material (PBR) playground!
Post by: maru on 2021-01-11, 15:59:05
it would probably be a good idea to allow  mapping ior values ​​with rgb where  ​​1.0 is 0.0.0 and 3.0 is 255.255.255, in this case we can easily clamp our speclvl map values ​​to 0-128 and get reasonable results. Just my thoughts.

Is this (screenshot attached) solution good enough for you, or would it be vital to have some kind of native Corona feature for this?

I've said it many times and always will - this setup is so cumbersome it hurts. Thinking this is good enough is a mistake, sorry.
You should map incoming images so that RGB 0 is IOR 1.0 and RGB 255 is the specified IOR in the material UI. Or make a new IOR map where users can specify the value mapping in a similar way.
But to me, your setup is just not sufficient in terms of use ease nor setup time, plus you can't see what the values specified are unless you inspect all nested maps, that's absolutely insane.
It looks like you guys are going the Autodesk way on this one - "half-assed will do it, let's not think any further."
I don't mean to offend, but we already discussed this elsewhere and it's frustrating you think it's good enough.

Your answer is exactly why I posted the question in the first place. Thanks.

(Report ID=CRMAX-168)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: pokoy on 2021-01-11, 20:42:49
Looking at my answer above I see that I should have put this in a more polite way, sorry for the harsh tone. I should back up my critique with screenshots and examples but I'm not going to be in front of my PC for the next 1-2 weeks and just can't be more specific right now. Not ideal, but I hope it's clear why the current approach isn't very user friendly right now.
What I dislike is that without inspecting maps or map trees you won't be able to tell what the IOR value is. Also, by using values outside of 0-1 map thumbnails will always be white, making it impossible to quickly check the final map, especially if you stack them you want to know what you're doing - an all white final map result won't tell you anything.
By mapping the map/map tree values instead you can immediately see what the final map stack is, since it displays in 0-255 and you specify the max IOR value in a numerical way right within the material's UI. This way you get the info much quicker with the same result.
I'm eager to see why others don't see anything wrong in going the more winded route. Maybe I'm missing something and judge too quickly.
Sorry again, Maru.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: maru on 2021-01-12, 10:26:40
No problem at all! I am happy to hear any feedback and actually using a more straightforward tone usually makes the message easier to understand.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: dacian on 2021-01-13, 20:46:06
How do you set a translucency color in the new material? other than the base color.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: maru on 2021-01-14, 11:31:44
How do you set a translucency color in the new material? other than the base color.

See:
Quote
we are aware that some of the features which are grayed out are not really clear UX/UI-wise on how to enable them. We have a fix ready in our development build, which should arrive to you soon.
In the meantime:
Translucency requires "Thin Shell" in General Tab
Refraction>Thin Absorbtion requires "Thin Shell" in General Tab
Opacity>Clip requires a texture map in the Opacity Texture
Volumetrics require refraction to be enabled
SSS requires Refraction at lower than 100 value.
Source: https://forum.corona-renderer.com/index.php?topic=31989.msg180472#msg180472
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Nejc Kilar on 2021-01-14, 12:41:34
How do you set a translucency color in the new material? other than the base color.

Seemingly you cannot quite do that anymore. GeorgeK posted this line a couple of pages ago: "In regards to your second question, the translucency fraction is still there labeled as "Translucency" you can enable it and use it without the use of a map simply by enabling the Thin Shell (no inside) option above Base Layer. The color of the translucency depends on your base layer color."

Maybe I'm wrong :D
Title: Re: New Corona Physical Material (PBR) playground!
Post by: maru on 2021-01-14, 13:12:56
Ah, damn, it looks like I misunderstood the question, sorry!
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Nejc Kilar on 2021-01-14, 13:43:31
Ah, damn, it looks like I misunderstood the question, sorry!

For what its worth, you answered a couple of my questions with it, ha! :)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marchik on 2021-01-19, 10:56:33
There is one more thing, due to the connection between roughness of reflections and roughness of refractions, it became virtually impossible to add, for example, fingerprints to the glass surface, because even the stained glass remains with 0 roughness, at first I thought that this could be solved with clearcoat but my attempts did not lead to anything good. It seems a little strange to me that when adding new functions, old ones break) and ofc the same concerns translucency color map, which in some cases just necessary

I hope you wont delete the legacy shader because sometimes some "fakes" lead to good results or maybe it will be a good idea to add "expert" mode in our new physical material which will break those "physicall correct connections"

And I also recently remembered how we discussed the idea of ​​adding a fake thickness function https://forum.corona-renderer.com/index.php?topic=15639.0 (https://forum.corona-renderer.com/index.php?topic=15639.0) for thin meshes that would allow using the opacity map to simulate an effect similar to corona round edges in legacy mode without having to make a separate super-detailed normal map. It would be a great addition to the new thin shell and volume switching function in the new shader


Title: Re: New Corona Physical Material (PBR) playground!
Post by: Nejc Kilar on 2021-01-19, 11:10:18
There is one more thing, due to the connection between roughness of reflections and roughness of refractions, it became virtually impossible to add, for example, fingerprints to the glass surface, because even the stained glass remains with 0 roughness, at first I thought that this could be solved with clearcoat but my attempts did not lead to anything good. It seems a little strange to me that when adding new functions, old ones break) and ofc the same concerns translucency color map, which in some cases just necessary
I hope you wont delete the legacy shader because sometimes some "fakes" lead to good results or maybe it will be a good idea to add "expert" mode in our new physical material which will break those "physicall correct connections"

I haven't tried it myself yet but I suspect that a potential workflow for this could revolve around having the glass be the base in a Corona Layered material while the fingerprints come on top with a mask using it's own separate material.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Mohammadreza Mohseni on 2021-01-19, 11:20:40
I hope the name of CoronaLegacyMtl class would go back to CoronaMtl class which would be really easier to find because of the years of habit and since it completely distinguishes itself from the CoronaPhysicalMtl class I did not grasp the need for changing the class name.

ps: I know it works with both in maxscript because of the compatibility and we have two class for one single thing but I mean the name that shows in the material editor
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marchik on 2021-01-19, 11:30:19
There is one more thing, due to the connection between roughness of reflections and roughness of refractions, it became virtually impossible to add, for example, fingerprints to the glass surface, because even the stained glass remains with 0 roughness, at first I thought that this could be solved with clearcoat but my attempts did not lead to anything good. It seems a little strange to me that when adding new functions, old ones break) and ofc the same concerns translucency color map, which in some cases just necessary
I hope you wont delete the legacy shader because sometimes some "fakes" lead to good results or maybe it will be a good idea to add "expert" mode in our new physical material which will break those "physicall correct connections"

I haven't tried it myself yet but I suspect that a potential workflow for this could revolve around having the glass be the base in a Corona Layered material while the fingerprints come on top with a mask using it's own separate material.

no doubt this can be solved, but what is the point in this innovation if it does not make working with the render engine easier?
In this case, we may not use maps for roughness or base color at all, but simply mix the necessary materials by masks: D: D: D
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-01-21, 10:37:56
it became virtually impossible to add, for example, fingerprints to the glass surface

Why isn't this solved by just passing a roughness / glossiness map into the roughness / glossiness channel of a refractive (glass) material? I would presume that would be sufficient for ~90% of cases - maybe even for the remaining edges cases in which a close-up is required(?)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marchik on 2021-01-21, 11:12:34
it became virtually impossible to add, for example, fingerprints to the glass surface

Why isn't this solved by just passing a roughness / glossiness map into the roughness / glossiness channel of a refractive (glass) material? I would presume that would be sufficient for ~90% of cases - maybe even for the remaining edges cases in which a close-up is required(?)

because even a refraction glossiness of 0.99 results in blurry unwanted results for me) ofc it is not "critical" but personal for me, i want to have an option to unlink refl/refr roughness
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-01-21, 14:36:49
it became virtually impossible to add, for example, fingerprints to the glass surface

Why isn't this solved by just passing a roughness / glossiness map into the roughness / glossiness channel of a refractive (glass) material? I would presume that would be sufficient for ~90% of cases - maybe even for the remaining edges cases in which a close-up is required(?)

because even a refraction glossiness of 0.99 results in blurry unwanted results for me) ofc it is not "critical" but personal for me, i want to have an option to unlink refl/refr roughness

Working with the coat layer for the fingerprints wouldn't solve your issue?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marchik on 2021-01-21, 20:24:33
Working with the coat layer for the fingerprints wouldn't work for your case?

logically, this approach should work, but I still cannot get it to produce a similar result. It would be logical to set the required roughness value for the coat layer and apply it using a contrast mask, but as a result, the picture is more noisy and the pattern of smudges does not turn out to be as clear, of course you can always tweak  this to death, but it seems to me that this should not work like that.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: pokoy on 2021-01-22, 10:41:01
I think the map should go into clearcoat roughness (inverted), not clearcoat amount. Clearcoat amount needs to be >0 then, of course.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-01-22, 15:24:20
^this 👏
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marchik on 2021-01-22, 19:43:01
I think the map should go into clearcoat roughness (inverted), not clearcoat amount. Clearcoat amount needs to be >0 then, of course.

Nope) you can try it yourself) as I said, a workaround can of course be found, but I cannot understand the ultimate purpose of this simplification if it only complicates the task.
PS and finally, if this is a "physically correct" shader, why should I add a layer of transparent glossy varnish to the glass if it is not there?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: romullus on 2021-01-22, 21:19:02
PS and finally, if this is a "physically correct" shader, why should I add a layer of transparent glossy varnish to the glass if it is not there?

Technically fingerprint marks are not the part of the glass, it's a layer of grease and dirt on top of the glass. Maybe using clearcoat is not the best solution, but physically it's more correct than making fingerprints as a property of the glass.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: pokoy on 2021-01-22, 22:42:31
Yes, some things are now easier to achieve by using LayerMtl. I don't like it myself that much but there's hardly a way to make everything easier with the new material.
The thing is that LayerMtl needs some work now too - displacement, bump, some properties only being used when in base material etc. The new PBR material certainly implies a few challenges here and there.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marchik on 2021-01-23, 10:30:50
PS and finally, if this is a "physically correct" shader, why should I add a layer of transparent glossy varnish to the glass if it is not there?

Technically fingerprint marks are not the part of the glass, it's a layer of grease and dirt on top of the glass. Maybe using clearcoat is not the best solution, but physically it's more correct than making fingerprints as a property of the glass.
Absolutely, but i'm talking about using clearcoat roughness parameter instead of clearcoat amount
I think the map should go into clearcoat roughness (inverted), not clearcoat amount. Clearcoat amount needs to be >0 then, of course.



in this case it is absolutely obvious that the glass surface without fingerprints is not covered with any clearcoat at all
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-01-23, 12:21:58
PS and finally, if this is a "physically correct" shader, why should I add a layer of transparent glossy varnish to the glass if it is not there?

Technically fingerprint marks are not the part of the glass, it's a layer of grease and dirt on top of the glass. Maybe using clearcoat is not the best solution, but physically it's more correct than making fingerprints as a property of the glass.
Absolutely, but i'm talking about using clearcoat roughness parameter instead of clearcoat amount
I think the map should go into clearcoat roughness (inverted), not clearcoat amount. Clearcoat amount needs to be >0 then, of course.



in this case it is absolutely obvious that the glass surface without fingerprints is not covered with any clearcoat at all

Some differences in roughness are to be expected, the underlying models in Physical material are different than in the legacy material. Diffuse reflection is different based on base glossiness/roughness, reflection is normalized (scaled in order to not lose energy) differently to be more physically plausible.

Comparison 1, HDRI lighting: https://corona-renderer.com/comparer/NugVgk
Comparison 2, two light sources: https://corona-renderer.com/comparer/Uw9dpN

In my opinion, I find the physical model to be more accurate, but I can see how this might need some effort into being get used to, as always if a lot of voices raise concern we will forward your criticism to the devs for further consideration.

(Report ID=CRMAX-71)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marchik on 2021-01-23, 13:34:34

Some differences in roughness are to be expected, the underlying models in Physical material are different than in the legacy material. Diffuse reflection is different based on base glossiness/roughness, reflection is normalized (scaled in order to not lose energy) differently to be more physically plausible.

Comparison 1, HDRI lighting: https://corona-renderer.com/comparer/NugVgk
Comparison 2, two light sources: https://corona-renderer.com/comparer/Uw9dpN

In my opinion, I find the physical model to be more accurate, but I can see how this might need some effort into being get used to, as always if a lot of voices raise concern we will forward your criticism to the devs for further consideration.

(Report ID=CRMAX-71)

Thank you very much, this is more likely not a criticism, I just try to use a new shader in my daily work and check as many controversial points and difficulties in use as possible, and accordingly I am writing about the results here.

I would also like to know the opinion of the dev team about the implementation of bump "replacement" in the clearcoat  layer as we mentioned before)
the item about the implementation of the new shader in the roadmap was fully checked yesterday and it makes me worried: D
Title: Re: New Corona Physical Material (PBR) playground!
Post by: boston.george on 2021-01-28, 16:15:01
Stupid question:

Where is reflection slot?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: enrico.lapponi on 2021-01-28, 17:57:21
Stupid question:

Where is reflection slot?

I think the slot we knew as Reflection now it's been incorporated in the Base layer under the Color option, which makes sense because in reality the base color and specular reflection are one thing, in cgi they are separated for artistic purposes, at least this is how I understand it. Also in the tool tip there is a simple explanation.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: n2graf on 2021-01-29, 18:34:31
For metallic materials that accumulate a thin layer of dust...

The issue is that metal and dust are two completely different materials. Layered Mtl would be definitely preferred here.
Maybe you could also use the built in Sheen layer? (you can specify its color, amount, and roughness so it's a bit like a layer of non-metal).


Yes they are completely different, but In the real world there are no pure metals, within seconds of leaving the furnace, they begin to oxidize in a very thin and superficial layer that itself serves as a shield so that the oxidation continues to advance inwards. In this way there will always be a certain mixture of non-metal in metallic materials. Having to always use multimaterial to solve this is very laborious and does not make sense. It is much more practical to be able to lower the amount of non-metal with a spinner and attach a slot for the diffuse color that is operative only when we activate the spinner.(http://)
Sheenlayer with roughtness at 1 does not work well. As you can see in the metal gold image, the blue sheenlayer is increased in the tangential parts when a diffuse one should mix equally in all areas.

Title: Re: New Corona Physical Material (PBR) playground!
Post by: Anatoly on 2021-02-01, 12:34:00
I suggest that you need to add a very understandable and detailed chapter on helpdek site (https://coronarenderer.freshdesk.com/support/home), explaining this "new" material approach with comparison to traditional one, and how one should migrate to it, filled with examples and tutorials.

I believe that it would take some effort for a lot of users, who used to classic approach, to start using this new one with the same ease. Currently I can imagine exactly what map should be in reflect, refract, diffuse, translucency, e.t.c. slot, to make material look as intended. This is not the case with PBR material, and you can see it by the questions above, and I believe that here is the progressive part of your audience.

Maybe it would be a good idea to add some script that converts traditional materials to Physical, converting and placing all maps correctly, to achieve correct result. Or may be some map node that would take a traditional diffuse, reflect, refract, translucency and other maps on the input, and generate correct output maps required for PBR, like roughness, metalness and others. This might help with asset migration and migration in general. One could see how new PBR maps should look like, to achieve the same (or close to the same) result as with the classic approach.

Thank you. Hope this make sense.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: mantaskava on 2021-02-01, 13:40:16
I suggest that you need to add a very understandable and detailed chapter on helpdek site (https://coronarenderer.freshdesk.com/support/home), explaining this "new" material approach with comparison to traditional one, and how one should migrate to it, filled with examples and tutorials.

Totally agree with Anatoly on this one.
I want to see various examples of various materials converted correctly from legacy to new PBR material (or in other words, in a way developer intended). All with clear explanations, like what bitmap goes where and why.
I don't want to spend another weak experimenting and guessing if it's the most efficient/correct way of doing this or that or not.
Hope you'll consider this and make it real.

Thanks
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-02-01, 13:55:25
I suggest that you need to add a very understandable and detailed chapter on helpdek site (https://coronarenderer.freshdesk.com/support/home), explaining this "new" material approach with comparison to traditional one, and how one should migrate to it, filled with examples and tutorials.

Totally agree with Anatoly on this one.
I want to see various examples of various materials converted correctly from legacy to new PBR material (or in other words, in a way developer intended). All with clear explanations, like what bitmap goes where and why.
I don't want to spend another weak experimenting and guessing if it's the most efficient/correct way of doing this or that or not.
Hope you'll consider this and make it real.

Thanks

Not just considering it, already doing it ;).

We are also looking into a viable and efficient conversion method between a legacy material and a physical one.

Thanks for your feedback.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-02-03, 12:56:13
Hi all,

Just so to clarify some things with regards to the IOR/Specular Mapping request.


Would it be possible to offer a practical example of this, I am assuming that this includes a workflow along with other software, if so yes can you please specify which?

Thanks.

(Report ID=CRMAX-168)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: niljut on 2021-02-03, 16:03:06
How set are the properties of the material? I don't have the opportunity to install the beta, but I would like to prepare some of my scripts for when it goes live. Could someone so kindly post the properties of the material class? Can be done by typing in Show CoronaPhysicalMaterial in the listener (assuming the class is named as such, otherwise Show $.material with an object selected that has the material applied should work, iirc)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: maru on 2021-02-03, 16:14:27
How set are the properties of the material? I don't have the opportunity to install the beta, but I would like to prepare some of my scripts for when it goes live. Could someone so kindly post the properties of the material class? Can be done by typing in Show CoronaPhysicalMaterial in the listener (assuming the class is named as such, otherwise Show $.material with an object selected that has the material applied should work, iirc)

I think it would be best to wait for the final version, because the current ui/properties can still change.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Fluss on 2021-02-09, 11:32:06
wow didn't check the forum in a while! That new shader looks sexy! I'll have to give it a try
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marchik on 2021-02-10, 02:45:45

Some differences in roughness are to be expected, the underlying models in Physical material are different than in the legacy material. Diffuse reflection is different based on base glossiness/roughness, reflection is normalized (scaled in order to not lose energy) differently to be more physically plausible.

Comparison 1, HDRI lighting: https://corona-renderer.com/comparer/NugVgk
Comparison 2, two light sources: https://corona-renderer.com/comparer/Uw9dpN

In my opinion, I find the physical model to be more accurate, but I can see how this might need some effort into being get used to, as always if a lot of voices raise concern we will forward your criticism to the devs for further consideration.

(Report ID=CRMAX-71)

with regard to the results, how were they achieved in this case? which parameter was mapped? clearcoat amount or clearcoat roughness?


And in addition, I may be wrong, but it seems to me that the format of the normal map has changed for the new material, is it so?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-02-10, 10:27:38

Some differences in roughness are to be expected, the underlying models in Physical material are different than in the legacy material. Diffuse reflection is different based on base glossiness/roughness, reflection is normalized (scaled in order to not lose energy) differently to be more physically plausible.

Comparison 1, HDRI lighting: https://corona-renderer.com/comparer/NugVgk
Comparison 2, two light sources: https://corona-renderer.com/comparer/Uw9dpN

In my opinion, I find the physical model to be more accurate, but I can see how this might need some effort into being get used to, as always if a lot of voices raise concern we will forward your criticism to the devs for further consideration.

(Report ID=CRMAX-71)

with regard to the results, how were they achieved in this case? which parameter was mapped? clearcoat amount or clearcoat roughness?


And in addition, I may be wrong, but it seems to me that the format of the normal map has changed for the new material, is it so?

The above examples were made with clearcoat gloss for the CoronaPhysicalMtl and reflection.gloss for the CoronaLegacyMtl, both materials shared the same maps in all slots and bump.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Fluss on 2021-02-12, 13:20:41
So we do not have control over the main specular lobe anymore?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: burnin on 2021-02-12, 16:27:16
Could you be more specific.
As I see it's not separated anymore but simply optimized by it being connected, dependent... as is in real world.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Fluss on 2021-02-12, 17:37:26
Yes, it's great when everything behaves physically but it's also great to keep control when we need to, for artistic or whatever reasons. Hope we at least can access this through additional params.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: LorenzoS on 2021-02-13, 20:54:05
Hi all,
the bump on base layer affect the clearcoat layer and consequently the surface reflection.
For my point of view it is should not, or this behavior is as expected?

Title: Re: New Corona Physical Material (PBR) playground!
Post by: burnin on 2021-02-13, 22:34:18
Hi all,
the bump on base layer affect the clearcoat layer and consequently the surface reflection.
For my point of view it is should not, or this behavior is as expected?
Well... Isn't 'clearcoat' just a 'thin coat'?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: lupaz on 2021-02-13, 22:43:54
Hi all,
the bump on base layer affect the clearcoat layer and consequently the surface reflection.
For my point of view it is should not, or this behavior is as expected?
Well... Isn't 'clearcoat' just a 'thin coat'?

It is, but like with snow, the upper surface should get evened out at one point. So it should/could have no or less bump than the base layer.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marchik on 2021-02-14, 06:14:24
Hi all,
the bump on base layer affect the clearcoat layer and consequently the surface reflection.
For my point of view it is should not, or this behavior is as expected?
Well... Isn't 'clearcoat' just a 'thin coat'?

It is, but like with snow, the upper surface should get evened out at one point. So it should/could have no or less bump than the base layer.
Thats what I'm talking about from the very beginning) we definitely need spinner to control a base bump influence on the clearcoat
Title: Re: New Corona Physical Material (PBR) playground!
Post by: LorenzoS on 2021-02-14, 10:12:13
this should be the correct result.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-02-14, 13:27:37
this should be the correct result.

We already have this logged for consideration :)

(Report ID=CRMAX-85)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: burnin on 2021-02-14, 14:22:14
this should be the correct result.
Right, I see now :)... since it has its own bump it should really be flat over when used & set in such way.
Sure then, a value (slider) to influence it and/or mix with bump under, could be another good feature to have.


///
Oof, am getting a bit slow, not interacting and brain storming as much as used to. 
Title: Re: New Corona Physical Material (PBR) playground!
Post by: ATa on 2021-02-20, 13:08:22
HI CORONA guyz... as a corona user over 2 years, i couldn't find out why we should have Corona mtl and this one (PBR) simultaneously with same behavior!? 🤔 instead of parallel parts i supposed that we see some dramatic improvements in VFX, caustics and speed of rendering for animating ANY WAY... infinite loop⁉ after Chaos group😐 plz be U r self_ forward thinking nothing more!
Title: Re: New Corona Physical Material (PBR) playground!
Post by: TomG on 2021-02-21, 14:26:44
HI CORONA guyz... as a corona user over 2 years, i couldn't find out why we should have Corona mtl and this one (PBR) simultaneously with same behavior!? 🤔 instead of parallel parts i supposed that we see some dramatic improvements in VFX, caustics and speed of rendering for animating ANY WAY... infinite loop⁉ after Chaos group😐 plz be U r self_ forward thinking nothing more!

Not sure what you mean, can you explain more? This material is not the same as the Legacy, e.g. the big obvious examples are that this one has Clear Coat and Sheen, but there are other differences under the hood too that makes this easier to use, less likely to create "fake" materials, and more compatible with other approaches to materials to make importing things from Quixel, Megascans, Substance etc. easier. All of those are the reasons why the material is changing.

As a note, the Physical Material is the new default and recommended to use - the old one is left in place simply for legacy scenes that use it, so you can continue to get identical results from your previous scenes (so that's why you end up with both materials, rather than just the new one).

The merger with Chaos Group has nothing to do with deciding it was time for a new material with more functionality and better compatibility, still entirely our own decision :)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: LorenzoS on 2021-02-21, 16:04:28
Hi,
what the future of legacy materials in actual Library?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: ATa on 2021-02-21, 19:19:04
TNX TomG, i mean why should we have the new tab as PBR? instead of improving current situation (corona MTL parameters) because after a couple of years users are completely compatible with them (any way, I'm worried it is just like another complexity or NT 🤔)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: zaar on 2021-02-22, 11:37:45
When looking at the new coat function, I'm thinking of something I wanted for a long time but never dared request: Wetness like in some game engines. So where there is a coat (of water) the underlying material gets darkened based on it's porosity, and maybe depending on how wet, the material either just gets damp/darkened (and gloss might be affected too?) and if it's really wet it gets a coat that also has a bumped edge?

It's not like this is impossible to set up. It's just that it would be very convenient to have built in to the material from the start. A lot of arch-viz people a lot of puddles :) And if the setup is smart I think it would interest some motion graphics and VFX-peeps too!?
Or maybe in future versions of Slate Max will let us make little macro nodes that multiply diffuse by an inverted wetmap and so on, so that you don't have to do this over and over if you have many ground materials that need to be affected by the same puddles.

disclaimer: I'm not on daily builds, just trying to keep up here on news about the new PBR material
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Visuali on 2021-02-24, 11:56:04
this should be the correct result.
Right, I see now :)... since it has its own bump it should really be flat over when used & set in such way.
Sure then, a value (slider) to influence it and/or mix with bump under, could be another good feature to have.

Maybe just a padlock on the Bump parameter of the Clearcoat layer would be enough to choose whether the two should have the same behavior as in the first image (Reply #104) or should be independent as in the second (Reply #108).
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Yuriy Bochkaryov on 2021-02-26, 11:42:07
this should be the correct result.
Right, I see now :)... since it has its own bump it should really be flat over when used & set in such way.
Sure then, a value (slider) to influence it and/or mix with bump under, could be another good feature to have.

Maybe just a padlock on the Bump parameter of the Clearcoat layer would be enough to choose whether the two should have the same behavior as in the first image (Reply #104) or should be independent as in the second (Reply #108).
I think it is a good idea
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marchik on 2021-02-26, 14:43:35
I think it is a good idea
Base layer bump intesity slider or  some "coat water level" or maybe fake "coat thiсkness" slider can be very usable for fast recreating porus absorption effect, espessialy on laquered wood without having to create a new bump map or modify the existing
(https://i.ibb.co/DD60q7j/coat-bump.jpg) (https://imgbb.com/)
(https://i.ibb.co/sq4pDkL/coat-bump2.jpg) (https://imgbb.com/)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: JoeS on 2021-03-03, 03:43:56
Any chance we will see some settings for an iridescent effect ?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-03-03, 11:20:55
Any chance we will see some settings for an iridescent effect?

It is in our plans for the future, granted that there's a popular demand for it.

Also worth looking into https://forum.corona-renderer.com/index.php?topic=14552.0

(Report ID=CRMAX-319)

Title: Re: New Corona Physical Material (PBR) playground!
Post by: JoeS on 2021-03-03, 23:49:00
Any chance we will see some settings for an iridescent effect?

It is in our plans for the future, granted that there's a popular demand for it.

Also worth looking into https://forum.corona-renderer.com/index.php?topic=14552.0

(Report ID=CRMAX-319)


Thanks (GeorgeK) I have tried using this technique in the link but for some reason I can't apply a reflection colour to the non-metal material. And metallic materials no longer have that option for refraction I cant make a bubble shader. If I use the the metalness slot on the non-metal material I lose the ability to tweak the reflection amount etc plus it looks strange. Any thoughts on this would be appreciated.

Cheers
 
Title: Re: New Corona Physical Material (PBR) playground!
Post by: burnin on 2021-03-04, 23:41:19
About Clearcoat, it'd  be really great to also have metalness option for it.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-03-05, 00:19:57
Any chance we will see some settings for an iridescent effect?

It is in our plans for the future, granted that there's a popular demand for it.

Also worth looking into https://forum.corona-renderer.com/index.php?topic=14552.0

(Report ID=CRMAX-319)


Thanks (GeorgeK) I have tried using this technique in the link but for some reason I can't apply a reflection colour to the non-metal material. And metallic materials no longer have that option for refraction I cant make a bubble shader. If I use the the metalness slot on the non-metal material I lose the ability to tweak the reflection amount etc plus it looks strange. Any thoughts on this would be appreciated.

Cheers

Well, iridescence could be also described as some sort of coating, and in many cases a form of thin-film covering organic surfaces and whatnot.  There are many ways to approach this, so far it will still be an artistic representation of the actual effect itself but it can come pretty close.  (Attaching 3ds max file with base shaders no textures)

(https://forum.corona-renderer.com/index.php?action=dlattach;topic=31802.0;attach=143654;image)

For CoronaPhysicalMtl you can use base color for metallics, or clearcoat absorption for dielectrics/non-metallics. You can control the effect with the amount of base color or absorption amount for clearcoat respectively.

(https://forum.corona-renderer.com/index.php?action=dlattach;topic=31802.0;attach=143652;image)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: JoeS on 2021-03-05, 23:05:45
Any chance we will see some settings for an iridescent effect?

It is in our plans for the future, granted that there's a popular demand for it.

Also worth looking into https://forum.corona-renderer.com/index.php?topic=14552.0

(Report ID=CRMAX-319)


Thanks (GeorgeK) I have tried using this technique in the link but for some reason I can't apply a reflection colour to the non-metal material. And metallic materials no longer have that option for refraction I cant make a bubble shader. If I use the the metalness slot on the non-metal material I lose the ability to tweak the reflection amount etc plus it looks strange. Any thoughts on this would be appreciated.

Cheers

Well, iridescence could be also described as some sort of coating, and in many cases a form of thin-film covering organic surfaces and whatnot.  There are many ways to approach this, so far it will still be an artistic representation of the actual effect itself but it can come pretty close.  (Attaching 3ds max file with base shaders no textures)

(https://forum.corona-renderer.com/index.php?action=dlattach;topic=31802.0;attach=143654;image)

For CoronaPhysicalMtl you can use base color for metallics, or clearcoat absorption for dielectrics/non-metallics. You can control the effect with the amount of base color or absorption amount for clearcoat respectively.

(https://forum.corona-renderer.com/index.php?action=dlattach;topic=31802.0;attach=143652;image)

GerogeK these shaders look great. But just like my tests they all look more like tinted glass then an iridescent material. I will make some render tests and post them.

On another note with the new physical material under volumetric scattering would it be possible to include the volume mapping options "on surface and inside volume" the same one that's in the corona volumetric material ?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-03-10, 12:51:06
Any chance we will see some settings for an iridescent effect ?

Hi again, I've managed to reproduce the issue with CoronaPhysical, it seems that indeed it's not that easy to get a nice "bubble result" without the use of a properly physically-correct thin-film addition.

As said previously I've logged a feature request for thin-film for CoronaPhysicalMtl.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Feodor on 2021-03-23, 01:12:48
I use this plugin.
https://www.sigerstudio.eu/sigertexmaps-thinfilm/
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-03-23, 11:29:23
Hi, as of the latest daily build of Corona 7 2021-03-22, If clearcoat bump map is not supplied, clearcoat does not use any bump-mapping (previously it used bump map from base layer). Further detailed info can be found here: [Behind the scenes: The Physical Material] (https://blog.corona-renderer.com/behind-the-scenes-the-physical-material/?fbclid=IwAR3eidlUiWGl_ctHWyBAiiXe4acjM6ydgJrs_p5gY8fJB2tvfoUF04LPr6o)

You can find the latest DB here: [Link] (https://www.dropbox.com/s/p1axf3mq9nmthfb/corona-7-3dsmax-daily-2021-03-22.exe?dl=0)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: ferrosoa on 2021-03-23, 16:00:41
Are you sure with new Iron preset in last daily? Why is red? Version before was gray, same result like using complexfresnel.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marchik on 2021-03-23, 16:34:08
Hi, as of the latest daily build of Corona 7 2021-03-22, If clearcoat bump map is not supplied, clearcoat does not use any bump-mapping (previously it used bump map from base layer). Further detailed info can be found here: [Behind the scenes: The Physical Material] (https://blog.corona-renderer.com/behind-the-scenes-the-physical-material/?fbclid=IwAR3eidlUiWGl_ctHWyBAiiXe4acjM6ydgJrs_p5gY8fJB2tvfoUF04LPr6o)

You can find the latest DB here: [Link] (https://www.dropbox.com/s/p1axf3mq9nmthfb/corona-7-3dsmax-daily-2021-03-22.exe?dl=0)
I observe strange behavior of the material if I add a normal bump map to the clearcoat bump slot, and vice versa, if I use a normal map in the base bump slot, then the clearcoat layer looks like inheriting the bumps of the base layer, is it expected?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: TomG on 2021-03-23, 17:02:08
I observe strange behavior of the material if I add a normal bump map to the clearcoat bump slot, and vice versa, if I use a normal map in the base bump slot, then the clearcoat layer looks like inheriting the bumps of the base layer, is it expected?
[/quote]

Not happening for me here - Corona Bitmap to Corona Normal to Base Bump, the Clear Coat is unaffected (unlike with the daily build before this one, be sure to be using the one from yesterday). Can you share images, grabs of the material set up, etc. ?

EDIT - or do you mean if you add a second normal, to the Clear Coat bump, only then does the Base Bump show through?

EDIT 2 - I tested the second case and I see what you mean, if there is a normal map in both Base and Clear Coat, the Base normal still affects the Clear Coat. It's not what I'd have expected so I will ask :)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marchik on 2021-03-23, 17:41:33


Not happening for me here - Corona Bitmap to Corona Normal to Base Bump, the Clear Coat is unaffected (unlike with the daily build before this one, be sure to be using the one from yesterday). Can you share images, grabs of the material set up, etc. ?

EDIT - or do you mean if you add a second normal, to the Clear Coat bump, only then does the Base Bump show through?

EDIT 2 - I tested the second case and I see what you mean, if there is a normal map in both Base and Clear Coat, the Base normal still affects the Clear Coat. It's not what I'd have expected so I will ask :)
ok, I recorded small video) but i cant totally understand what is going on. With some maps, for example default procedural noise connected through CoronaBumpConverter all work as expected, with some normal bump maps don't
Title: Re: New Corona Physical Material (PBR) playground!
Post by: TomG on 2021-03-23, 21:07:22


Not happening for me here - Corona Bitmap to Corona Normal to Base Bump, the Clear Coat is unaffected (unlike with the daily build before this one, be sure to be using the one from yesterday). Can you share images, grabs of the material set up, etc. ?

EDIT - or do you mean if you add a second normal, to the Clear Coat bump, only then does the Base Bump show through?

EDIT 2 - I tested the second case and I see what you mean, if there is a normal map in both Base and Clear Coat, the Base normal still affects the Clear Coat. It's not what I'd have expected so I will ask :)
ok, I recorded small video) but i cant totally understand what is going on. With some maps, for example default procedural noise connected through CoronaBumpConverter all work as expected, with some normal bump maps don't

After some more digging, I noticed this - if I checked the "Add gamma to input" in the Corona Normal for the Clearcoat Bump, the Base Bump no longer showed through (changing it in the Base layer Corona Normal did not make a difference). So looks like if the normals are wrong in the Clearcoat bump, it will let the Base bump have an effect.

This would explain why it happens sometimes but not other times, as it would depend on whether the Clearcoat bump has wrong normals (I did get the Corona warning about a Normal map being potentially incorrect).

Can you check and see if this is the same for you please? May also want to check the same for your Base layer, as it might depend on which Normal map is incorrect. Thanks!

Title: Re: New Corona Physical Material (PBR) playground!
Post by: marchik on 2021-03-23, 22:21:48

After some more digging, I noticed this - if I checked the "Add gamma to input" in the Corona Normal for the Clearcoat Bump, the Base Bump no longer showed through (changing it in the Base layer Corona Normal did not make a difference). So looks like if the normals are wrong in the Clearcoat bump, it will let the Base bump have an effect.

This would explain why it happens sometimes but not other times, as it would depend on whether the Clearcoat bump has wrong normals (I did get the Corona warning about a Normal map being potentially incorrect).

Can you check and see if this is the same for you please? May also want to check the same for your Base layer, as it might depend on which Normal map is incorrect. Thanks!
I think i got it, it is not a gamma related issue, i usually load my maps with override 1.0 gamma using DropToSlate plug-in, what I discovered right now is that when i use low intense, low "contrast" normal maps - then it gives incorrect results, transfering the bump details to the coat layer, you can check this in the video i've attached
in other words, some normal maps give incorrect results because their intensity is too low
PS I put video to .rar because it is too big for attachment
Title: Re: New Corona Physical Material (PBR) playground!
Post by: TomG on 2021-03-24, 14:50:32
Some more digging into it on this side, and it seems that if the base bump is dramatic/intense, it may affect the Clearcoat. A fix is being worked on to limit this issue, so keep an eye out for that in a future daily. Just to manage expectations, due to the nature of bump mapping it may not fix 100% of all possible cases, so we'd welcome your testing with any known examples to see how it works (once the fix is available, of course). Thanks!
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Duron on 2021-03-26, 18:04:34
I have installed the latest build today to check the new physical material and the first issue i came accross is this one with base bump affecting clearcoat.

Not only that the base bump is affecting the coat layer, even the bump isn't calculated like it should (see first two images below).
Title: Re: New Corona Physical Material (PBR) playground!
Post by: shortcirkuit on 2021-03-29, 00:01:55
nice flakes map - where might i find that online?
I have installed the latest build today to check the new physical material and the first issue i came accross is this one with base bump affecting clearcoat.

Not only that the base bump is affecting the coat layer, even the bump isn't calculated like it should (see first two images below).
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-03-29, 17:06:21
I have installed the latest build today to check the new physical material and the first issue i came accross is this one with base bump affecting clearcoat.

Not only that the base bump is affecting the coat layer, even the bump isn't calculated like it should (see first two images below).

Thanks Duron, this seems to be an issue with blurred input values/maps. I am reporting this for further assessment.

(Report ID=CRMAX-392)

Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-04-06, 08:45:48
That would be your base roughness or base glossiness slot, but keep in mind that you have to invert the values of your glossiness map if you are using roughness.

Is this issue (https://forum.corona-renderer.com/index.php?topic=28250.0) persistent in the Physical Material?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-04-06, 09:03:47
I'm reluctant to ask, but how is the Physical Material being handled by external integration partners, e.g. Quixel, Allegorithmic, etc.? I suspect this question is outside the scope of this forum thread, but the direct and obvious implication the Physical Material has for external asset libraries is very extreme in terms of asset migration.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Juraj on 2021-04-06, 09:46:30
I'm reluctant to ask, but how is the Physical Material being handled by external integration partners, e.g. Quixel, Allegorithmic, etc.? I suspect this question is outside the scope of this forum thread, but the direct and obvious implication the Physical Material has for external asset libraries is very extreme in terms of asset migration.

Bump :- ) I already asked this elsewhere and Maru gave elusive answer ("Maybe we are already talking" or something like that).

Would be really good if this was supported by Quixel Megascans exporter early. The current exporter sucks but they should have less excused why their convertion is weird when the new Physical material is industry-standard PBR.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-04-06, 11:21:34
Is there already a global setting (e.g. system settings, dev / exp stuff) to toggle the default 'roughness mode' of the Physical Material so that the roughness / glossiness does not need to be enabled a la carte?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: romullus on 2021-04-06, 11:25:45
+100 to the request above.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-04-06, 12:16:57
Hi everyone,

@Juraj, it is currently being taken care of. (elusively as always)

@cjwidd, @romullus, Already in the works as well :).
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Duron on 2021-04-06, 12:55:54
Ok from what i can tell you today is that the new PhysicalMtl is not made for carpaints and other painted metallic mixed surfaces with clearcoats.

I don't know if this is intentional, but uncontrollable things happen.
If you make a fresh new physicalMtl and change metallnes to metal and add a full red base colour 128.0.0 with roughness to 0.3, you can see that the red colour is changing to your light source by angle. Weird...
Now if you change the base colour to 64.0.0 you get a pinkish output which doesn't makes sense.

Im working with the phsyical material for few days now and it makes much fun. I really would like to use it as my standard mtl.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Duron on 2021-04-06, 17:26:05
One thing which was always a difficult approach for me was, light behind frosted glass.

In the attachement you can see an example of Roughness 0 to Roughness 0.01.
I quite not understand why a frosted glas can block soo much light. I understand that at some point like 0.4-0.6 you loose a lot but why already at 0.01? It seems like it clamps right above 0.

This behavior is also happening with the LegacyMtl. Can somebody maybe explain if this is intentional? Thank you.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-04-06, 20:15:36
Ok from what i can tell you today is that the new PhysicalMtl is not made for carpaints and other painted metallic mixed surfaces with clearcoats.

I don't know if this is intentional, but uncontrollable things happen.
If you make a fresh new physicalMtl and change metallnes to metal and add a full red base colour 128.0.0 with roughness to 0.3, you can see that the red colour is changing to your light source by angle. Weird...
Now if you change the base colour to 64.0.0 you get a pinkish output which doesn't makes sense.

Im working with the phsyical material for few days now and it makes much fun. I really would like to use it as my standard mtl.

Hi again, thanks for reporting those. This is highly likely unwanted we will be looking into it further.

Title: Re: New Corona Physical Material (PBR) playground!
Post by: pokoy on 2021-04-06, 20:38:53
One thing which was always a difficult approach for me was, light behind frosted glass.

In the attachement you can see an example of Roughness 0 to Roughness 0.01.
I quite not understand why a frosted glas can block soo much light. I understand that at some point like 0.4-0.6 you loose a lot but why already at 0.01? It seems like it clamps right above 0.

This behavior is also happening with the LegacyMtl. Can somebody maybe explain if this is intentional? Thank you.
I guess it's switching rendering modes as soon as any roughness is introduced. Since there are two different algorithms used (layman here, no idea if true) there's no way to get a smooth transition. I fought many times against this effect when using mapped glossiness for very subtle effects and finally accepted that it isn't possible.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-04-06, 20:54:11
Hi everyone,

@Juraj, it is currently being taken care of. (elusively as always)

@cjwidd, @romullus, Already in the works as well :).

Nice, thanks!
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Duron on 2021-04-07, 21:47:21
Is the PhysicalMtl supports MultiTile Map for using UDIMS already?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-04-08, 03:23:00
Not having any visibility into the actual mechanisms controlling the sheen layer - a sort of analog to the falloff map - it seems like:
Curious if that is a reasonable way of thinking about it(?)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-04-08, 10:08:57
I spent a lot of time experimenting with the new 'sheen layer,' and for some reason I had it in my head that the sheen layer was intended as a sort of catch-all method to address fabric shading in Corona Renderer without falloff maps; to obviate the need for falloff maps in fabric shading. I think that was a gross misinterpretation on my part because the sheen layer really is not flexible enough in its implementation to address very many fabric types - it is equipped to address velvet, satin, silk, etc.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-04-08, 11:42:54
I spent a lot of time experimenting with the new 'sheen layer,' and for some reason I had it in my head that the sheen layer was intended as a sort of catch-all method to address fabric shading in Corona Renderer without falloff maps; to obviate the need for falloff maps in fabric shading. I think that was a gross misinterpretation on my part because the sheen layer really is not flexible enough in its implementation to address very many fabric types - it is equipped to address velvet, satin, silk, etc.

The primary goal of Sheen is an easy simulation of the effect of subsurface scattering in the fibers, so any further customization options would highly likely deviate from sheen itself (and physical correctness). With that said we are always open to improvements or further feature requests that could potentially make it much better/flexible.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-04-08, 12:03:15
One thing which was always a difficult approach for me was, light behind frosted glass.

In the attachement you can see an example of Roughness 0 to Roughness 0.01.
I quite not understand why a frosted glas can block soo much light. I understand that at some point like 0.4-0.6 you lose a lot but why already at 0.01? It seems like it clamps right above 0.

This behavior is also happening with the LegacyMtl. Can somebody maybe explain if this is intentional? Thank you.

I am afraid this is a known issue with fake glass (no caustics enabled) but also a bug that we are planning to address.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-04-09, 00:37:34
The primary goal of Sheen is an easy simulation of the effect of subsurface scattering in the fibers, so any further customization options would highly likely deviate from sheen itself (and physical correctness).

Is that to say the sheen layer is meant as a sort of artistic embellishment, or is it offering a physically correct look by default?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Juraj on 2021-04-09, 16:16:08
The primary goal of Sheen is an easy simulation of the effect of subsurface scattering in the fibers, so any further customization options would highly likely deviate from sheen itself (and physical correctness).

Is that to say the sheen layer is meant as a sort of artistic embellishment, or is it offering a physically correct look by default?

Truth be told I don't know myself how to use it properly :- ).

One important aspect I found, is that it's good idea to "map" the intensity of the effect, instead of using pure numerical value. No fabric is smooth enough to create the sheen effect uniformly, the effect follows the structure so the structure needs to be converted into map that drives the effect intensity.

How that conversion should be done, is purely artistic interpretation. It's one of those "fake, but not fake" approaches to PBR that is necessary because real fabric is incredibly complex and mapping shader to a flat plane does pretty bad job most of the time, making "pure" PBR approach impossible. Just like Ambient Occlusion being mapped onto Albedo is necessary for most scanned materials (like rocks, grass, etc...)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-04-09, 22:43:47
One important aspect I found, is that it's good idea to "map" the intensity of the effect, instead of using pure numerical value. No fabric is smooth enough to create the sheen effect uniformly, the effect follows the structure so the structure needs to be converted into map that drives the effect intensity.

Ah I see, this is very helpful, thanks!
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-04-09, 23:15:56
One important aspect I found, is that it's good idea to "map" the intensity of the effect, instead of using pure numerical value. No fabric is smooth enough to create the sheen effect uniformly, the effect follows the structure so the structure needs to be converted into map that drives the effect intensity.

Ah I see, this is very helpful, thanks!

Sheen also cooperates very well with displacement, it also seems to do lovely for certain fruits (or seeds) that have fuzzy skin :).
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-04-10, 01:03:23
it also seems to do lovely for certain fruits (or seeds) that have fuzzy skin :).

Would love to see some example renders of this effect in action if any are available
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-04-11, 16:39:34
it also seems to do lovely for certain fruits (or seeds) that have fuzzy skin :).

Would love to see some example renders of this effect in action if any are available

So far I've been applying Sheen to peaches and some watermelons, works great with Kiwi too but needs some more tunning along with scattering.
The biggest benefit as I see it, it's that I had to only work with 60k fibre strands instead of 600k for Cscatter, the rest of the colouration that I wanted is coming from Sheen. I will post some examples again at a later date for release highlights.

But for the moment, in the Kiwi case, I exaggerate the effect a bit to notice its strengths and weaknesses on the model, a mask always helps:
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-04-12, 23:03:51
Really looks good +1

Any chance you could do a 5-10min walkthrough of how you approached the shading of this asset, e.g. fibre modeling, scattering, shader setup, etc.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-04-14, 12:22:01
Really looks good +1

Any chance you could do a 5-10min walkthrough of how you approached the shading of this asset, e.g. fibre modeling, scattering, shader setup, etc.

Surething! I will try and make a short guide-approach :), I will also fix scatter base inconsistency with sheen (highly likely this will result in a feature request).
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cgiout on 2021-04-15, 08:55:52
Hi guys. Any chance to have also an upgraded material library with brand new physical materials in the future?

Thanks
Raf
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-04-15, 09:05:21
Surething! I will try and make a short guide-approach :), I will also fix scatter base inconsistency with sheen (highly likely this will result in a feature request).

Nice, looking forward to it!
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-04-15, 09:28:33
Hi guys. Any chance to have also an upgraded material library with brand new physical materials in the future?

Thanks
Raf

This is also being addressed, please stay tunned.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: romullus on 2021-04-15, 10:40:12
#1 it would be nice if presets would be grouped by categories, e.g. metals, transparent, plastics, fabrics, etc. Basic alphabetical sorting is not enough, especially if the list will grow larger in the future.

#2 don't know how others, but i hate when you can change presets just by hovering mouse pointer over contracted list and rolling the mouse wheel. Since mouse wheel is most often used to navigate throgh UI, i always feel insecure to accidentally change some parameter. I know that this is global "issue" in 3ds max, but maybe it's possible to override this behaviour? IMO, the best practice is, when user has to click on, or expand scroll list, before he's allowed to scroll through it with mouse wheel.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-04-19, 11:43:28
#1 it would be nice if presets would be grouped by categories, e.g. metals, transparent, plastics, fabrics, etc. Basic alphabetical sorting is not enough, especially if the list will grow larger in the future.

#2 don't know how others, but i hate when you can change presets just by hovering mouse pointer over contracted list and rolling the mouse wheel. Since mouse wheel is most often used to navigate throgh UI, i always feel insecure to accidentally change some parameter. I know that this is global "issue" in 3ds max, but maybe it's possible to override this behaviour? IMO, the best practice is, when user has to click on, or expand scroll list, before he's allowed to scroll through it with mouse wheel.


Hey Romullus, regarding your first request I will have to get back to you on that.

About #2, from the moment you introduce some edits to your CoronaPhysicalMtl, if you accidentally scroll on the presets you will get a warning asking you if you really wish to continue with the change, and thus preventing any unwanted changes.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: romullus on 2021-04-19, 15:26:28
About #2, from the moment you introduce some edits to your CoronaPhysicalMtl, if you accidentally scroll on the presets you will get a warning asking you if you really wish to continue with the change, and thus preventing any unwanted changes.

IMHO that's not the best solution - if scroll list wouldn't be scrollable when contracted, then you wouldn't need that warning pop-up window in the first place.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-04-19, 22:45:34
I take advantage of the ability to scroll lists in the interface while contracted very often, e.g. VFB LUT. I don't know that I would be bothered if that behavior were limited in the shader preset rollout, but I definitely would not want that behavior to be limited globally throughout the interface.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-04-19, 22:50:22
You can map metalness, roughness, and IOR.

How do you map metalness in the Physical Material?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: pokoy on 2021-04-19, 23:21:57
About #2, from the moment you introduce some edits to your CoronaPhysicalMtl, if you accidentally scroll on the presets you will get a warning asking you if you really wish to continue with the change, and thus preventing any unwanted changes.

IMHO that's not the best solution - if scroll list wouldn't be scrollable when contracted, then you wouldn't need that warning pop-up window in the first place.
This could be a side-effect of the Qt interface, something similar happens with the Composite map since the switch to Qt which didn't happen in <2016 versions.
What if you put the preset list into a collapsable rollout? That way, once collapsed it's not accessible anymore and would remember its state on material change. Sure, not the most elegant solution, then again, presets might not be of interest once you start tweaking your material.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-04-21, 10:06:21
Organization of the shader rollout dialog is not my favorite at the moment

(https://i.imgur.com/YvXDR9v.jpg)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Duron on 2021-04-21, 22:25:28
Just wanted to share my excitement with you as i saw the latest build change log. WOW!

Thank you soo much for fixing the base bump and metal colour issue! You guys rrrrrrrrrrrrrrock!
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-04-22, 16:51:14
Just wanted to share my excitement with you as i saw the latest build change log. WOW!

Thank you soo much for fixing the base bump and metal colour issue! You guys rrrrrrrrrrrrrrock!

Cheers Duron! Thanks for reporting those in the first place.

Quote
Organization of the shader rollout dialog is not my favorite at the moment

The ever-evading ordering, let me see if we can re-arange those, thanks.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Feodor on 2021-05-24, 00:42:25
New physical material bomb, now you can make CDs with it!
Do the developers themselves know about this possibility? This is not documented anywhere.


Title: Re: New Corona Physical Material (PBR) playground!
Post by: lupaz on 2021-05-24, 01:08:17
New physical material bomb, now you can make CDs with it!
Do the developers themselves know about this possibility? This is not documented anywhere.

20 years late
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-05-24, 02:07:41
now you can make CDs with it!

How?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Feodor on 2021-05-24, 09:24:05
now you can make CDs with it!

How?

Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-05-25, 01:37:47
New physical material bomb, now you can make CDs with it!
Do the developers themselves know about this possibility? This is not documented anywhere.

Pretty awesome :).
Title: Re: New Corona Physical Material (PBR) playground!
Post by: romullus on 2021-05-25, 10:15:20
20 years late

I'm pretty sure you could do this in earlier Corona versions too - we have dispersion for quite some time.

@Feodor, thanks for sharing your setup. May i ask why you decided to modify gradient ramp in aniso rotation slot that way? I think default settings with only the type being changed to spiral, would give you more physically accurate result.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Feodor on 2021-05-25, 10:29:11
20 years late

I'm pretty sure you could do this in earlier Corona versions too - we have dispersion for quite some time.

@Feodor, thanks for sharing your setup. May i ask why you decided to modify gradient ramp in aniso rotation slot that way? I think default settings with only the type being changed to spiral, would give you more physically accurate result.

Previously, such a material could not be made, the dispersion worked only on refraction. In the Physical Material, it is taken into account when reflecting. From my personal experience (I may be wrong) Corona is the first render where I managed to make CD material!
Title: Re: New Corona Physical Material (PBR) playground!
Post by: maru on 2021-05-25, 12:32:02
Sorry, but this really was possible in older versions of Corona. The attached is a V6 render.
And here is a post with CDs from 2013 :)
https://forum.corona-renderer.com/index.php?topic=577.msg5982#msg5982
Title: Re: New Corona Physical Material (PBR) playground!
Post by: lupaz on 2021-05-25, 13:13:54
20 years late

I'm pretty sure you could do this in earlier Corona versions too - we have dispersion for quite some time.
It was a joke: like, who needs to render cds anymore.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-05-25, 16:20:14
20 years late

I'm pretty sure you could do this in earlier Corona versions too - we have dispersion for quite some time.

@Feodor, thanks for sharing your setup. May i ask why you decided to modify gradient ramp in aniso rotation slot that way? I think default settings with only the type being changed to spiral, would give you more physically accurate result.

Previously, such a material could not be made, the dispersion worked only on refraction. In the Physical Material, it is taken into account when reflecting. From my personal experience (I may be wrong) Corona is the first render where I managed to make CD material!

On the context of previously not possible to make materials, do try Aerogel, it's great with the new PhysicalMtl :).
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Feodor on 2021-05-25, 18:49:41
Sorry, but this really was possible in older versions of Corona. The attached is a V6 render.
And here is a post with CDs from 2013 :)
https://forum.corona-renderer.com/index.php?topic=577.msg5982#msg5982

I have some doubts about the physical correctness of the 2013 method. And with the 6 Corona it would be interesting to see the material settings, what did I miss!)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Yuriy Bochkaryov on 2021-06-14, 17:14:02
New physical material does not work correctly with the map in IOR
I think you need to check and fix it.
Adding a texture to the IOR slot does not draw on reflections.
For the texture to start working, you need to increase its RGB multiplier Level - this is not correct, because the texture has a normal contrast and should already work
Also, if you switch from IOR mode to Specular mode, then the texture starts working.
Please check.

P / S "black - increase, white - decrease" - a bit unusual and probably not logical, but perhaps it was done for convenience using Roughness

Title: Re: New Corona Physical Material (PBR) playground!
Post by: maru on 2021-06-15, 16:32:55
New physical material does not work correctly with the map in IOR
I think you need to check and fix it.
Adding a texture to the IOR slot does not draw on reflections.
For the texture to start working, you need to increase its RGB multiplier Level - this is not correct, because the texture has a normal contrast and should already work
Also, if you switch from IOR mode to Specular mode, then the texture starts working.
Please check.

P / S "black - increase, white - decrease" - a bit unusual and probably not logical, but perhaps it was done for convenience using Roughness

I have some info here, since this appears to be an important issue:

The way IOR mapping currently works (and always worked) is this:
- if the value is above 1, it is directly applied as IOR (e.g. value 1.5 = IOR 1.5)
- if the value is below 1, it is converted into 1/IOR (e.g. value 0.5 = 1/0.5 = 2)

This is why you are getting the "black = increase" effect.

8-bit textures like JPGs will have RGB values 255 or less, which means less than 1.
If you need to get the "brighter = increase" effect, you either have to use a texture with higher bit depth (like EXR) or you need to manually boost the texture's RGB level to go above RGB 255.

Honestly, I am not sure what at typical IOR texture looks like. Could you share some examples? Where does your texture come from? Do you know of some commonly used software that can generate IOR textures?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: pokoy on 2021-06-15, 17:51:35
I still think that remapping of texture values from 0-255 to '1-user value' would have been the most reasonable way to go. The current way is just a big question mark, while remapping would have been self-explained if available right in the material's UI. Nothing works without adding extra nodes anymore the way it is right now.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Juraj on 2021-06-15, 17:57:47
I take what I wrote below back, I forgot it's Substance that introduced the 1/IOR mapping texture. I don't want to tinker with industry standard.


------------------------------------------------------------------------------------------


I still think that remapping of texture values from 0-255 to '1-user value' would have been the most reasonable way to go. The current way is just a big question mark, while remapping would have been self-explained if available right in the material's UI. Nothing works without adding extra nodes anymore the way it is right now.

I see a perfect way implement this :- D

Quote
- if the value is above 1, it is directly applied as IOR (e.g. value 1.5 = IOR 1.5)
- if the value is below 1, it is converted into 1/IOR (e.g. value 0.5 = 1/0.5 = 2)

Who on earth would use the second method (below 1) to create 1/IOR? Let's just change that one method and we'll have both approaches at same time. Full backwards compatibility, full IOR mode override and full easy flexibility. Everyone could be happy?

Like this:

If the value is above 1, it is applied directly as IOR override (exactly as right now).
If the value is below 1, it will directly map as fraction of existing material IOR. Example value 0.5 will halve the reflectance of material IOR 1.52 (so something like 1.333 I don't know the math from head).

Did I miss something, looks ok to me but I also have brutal migraine right now..
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Yuriy Bochkaryov on 2021-06-15, 19:47:31
Quote
Do you know of some commonly used software that can generate IOR textures
we do not need a program to generate IOR textures, it should work with any texture, with any image, based on the gradation of dark and light, where dark adds IOR and light removes IOR - or vice versa, it doesn't matter, the algorithm subtracts from light to dark, this allows us to define areas with and without reflection on one object through the texture.
For example - a leaf of a tree, the leaf has veins that have no reflection, and another zone of the leaf has a reflection, this makes our picture realistic.
It is impossible for the entire sheet to have the same IOR value, this is not correct.
I’m not saying that your theory is not correct, I’m saying that we probably have an error somewhere in the work of IOR with textures
Please note that when switching IOR mode to Specular mode, the texture starts to work. If everything is correct, then there should be no changes in the reflection when switching different modes to IOR.
I tried a texture with 16 bit depth and the problem persisted.
I also observed problems - when I tried to adjust the IOR through the texture in the color-correction and it did not work, RGB level 0 and level 1000 always gave reflection, but the texture at RGB 1000 was absolutely white, and at RGB 0 it was absolutely black. The reflection was of different strengths, but it was a reflection. Although, within the maximum range of 0 and 1000, I should have had maximum reflection at one value, and complete lack of reflection at the other.
The working range for the color corestore was approximately 120-180 in the RGB, all other values ​​of the RGB multiplier simply did not work, there was no texture on the reflection, it was just a mirror with different reflection strength
Also, if you check the Invert checkbox on the texture, then the card starts working - this also indicates that the work is incorrect, because the invert should swap the reflection and its absence, and not turn the texture on and off.
You need to make tests with a simple texture, with 3d max procedural maps everything works fine, the problem is in raster textures
Another oddity - texture in IOR through color correction with RGB 500 - has the correct reflection pattern, if you make RGB 700, then the texture is perceived as inverted for reflection, but the texture itself remains the same, but the texture itself has become brighter, but not inverted, why is it in IOR perceived as inverted?
I think we have obvious problems with the perception of the range of brightness of the texture, somewhere there is an error in converting the brightness of pixels to IOR values

 
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Mohammadreza Mohseni on 2021-06-15, 19:51:08


I have some info here, since this appears to be an important issue:

The way IOR mapping currently works (and always worked) is this:
- if the value is above 1, it is directly applied as IOR (e.g. value 1.5 = IOR 1.5)
- if the value is below 1, it is converted into 1/IOR (e.g. value 0.5 = 1/0.5 = 2)


really???? wow. that's is strange behavior. really not expecting it.
personally, I always used EXR for it so not expected it to behave like that for 8 bits.

IOR generated from something like substance painter for corona would really look strange with this current behavior. I would expect this to be in the tooltip so if someone generated a map from substance ecosystem or other texturing applications to at least know about this and only generate 16 or 32-bit exr to use in corona.
I think at least more than half of those who use substance painter and corona use this incorrectly with the wrong exporting format.

Quote
Like this:

If the value is above 1, it is applied directly as IOR override (exactly as right now).
If the value is below 1, it will directly map as fraction of existing material IOR. Example value 0.5 will halve the reflectance of material IOR 1.52 (so something like 1.333 I don't know the math from head).

Did I miss something, looks ok to me but I also have brutal migraine right now..

thats something that we can imagine really easily and it works really well
Title: Re: New Corona Physical Material (PBR) playground!
Post by: romullus on 2021-06-15, 20:21:57
really???? wow. that's is strange behavior. really not expecting it.
personally, I always used EXR for it so not expected it to behave like that for 8 bits.

IOR generated from something like substance painter for corona would really look strange with this current behavior. I would expect this to be in the tooltip so if someone generated a map from substance ecosystem or other texturing applications to at least know about this and only generate 16 or 32-bit exr to use in corona.
I think at least more than half of those who use substance painter and corona use this incorrectly with the wrong exporting format.

Substance generates IOR maps that are 1/x IOR, so it should work in Corona out of the box. If you have evidence that it's not the case, then please share it with community.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Juraj on 2021-06-15, 21:39:24
For example - a leaf of a tree, the leaf has veins that have no reflection, and another zone of the leaf has a reflection, this makes our picture realistic.
It is impossible for the entire sheet to have the same IOR value, this is not correct.

That is not entirely true, the leaf in 99perc. of cases has the same IOR value/Specular value across its surface. But due to its surface micro-structure variation, which in CGI PBR model will translate to modulation with roughness(/glossiness) and normal map(/bump/displacement).

But because nothing in CGI can perfectly capture all the irregularities of real world, not even gigantic normal maps, micro occlusions, cracks and many tiny imperfections have to be simulated using "fake" methods. The result is not fake at all ! This is where specular modification applies. Or modification of IOR. Same thing, but the specular map is easier to work with since it's most similar to former reflection map.

Unreal Documentation on PBR material explains it nicely:
Quote
Commonly, if we modify Specular, we do so to add micro occlusion or small scale shadowing, say from cracks represented in the normal map


Specular 0.5 is IOR 1.52, the CoronaPhysicalMaterial nicely translates this value for you when you keep changing the modes.

To simulate former behavior of reflection slot, here is quick tutorial of one particular common scenario:

LegacyMaterial: IOR 1.52, Reflection 1.0, Reflection map B&W with 0 value in map being Reflection 0.0 (and thus IOR 1.0) and 255 being Reflection 1.0 (and thus specified IOR 1.52).

PhysicalMaterial: IOR 1.52 translates as Specular 0.5 (this is industry standard formular, Corona didn't make it up, look Unreal or Substance documentation), so B&W map with 0 value will be IOR 1.0, 128 (linear mid-grey) will be 1.52 and 255 will be IOR 1.8.

To use the same reflection maps previously with IOR 1.52 as specular maps just clamp them by half.

I know written like this it might seem complex, but I presume it will become second nature soon. This is industry standard now and will make translating between Substance/Quixel/etc.. assets much easier. There just a lot of options, and multiple workflows, which will be confusing at first. It's best to pick one (roughness or gloss, IOR or specular) and stick with that.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: lupaz on 2021-06-15, 23:08:51
I don't know what you guys think, but I'd pay the guy that used to do these Corona tutorials to make one for Physical material and all the things you are talking about here. He was awesome, and maybe if we all chip in he can get a good chunk of money and would be interested in doing one more tutorial. I don't know his name, so I can't contact him.

ab_channel=CoronaRendererCoronaRenderer
Title: Re: New Corona Physical Material (PBR) playground!
Post by: TomG on 2021-06-15, 23:40:51
As mentioned before, it's not about the money or anything else, he wanted to move on to other projects that were not tutorials. We will be having new tutorials though, and with an equally awesome presenter, so never fear in that regard :)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Yuriy Bochkaryov on 2021-06-15, 23:42:19
Quote
PhysicalMaterial: IOR 1.52 translates as Specular 0.5 (this is industry standard formular, Corona didn't make it up, look Unreal or Substance documentation)
if this is really a new industry standard, then you have to get used to it, this is not a problem. It just looks strange to me and I am worried that it may turn out to be a mistake, I will do a lot of work on my library, and then the development team will recognize it as a mistake and change the algorithm and it will break my whole library, it will be a very unpleasant surprise )
Title: Re: New Corona Physical Material (PBR) playground!
Post by: lupaz on 2021-06-16, 00:51:10
As mentioned before, it's not about the money or anything else, he wanted to move on to other projects that were not tutorials. We will be having new tutorials though, and with an equally awesome presenter, so never fear in that regard :)

Great.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-06-16, 02:14:23
just so I'm clear, if I set the IOR to 1.52 and I pass in a bitmap that contains black and white pixels, the white pixels will render as 1.52 IOR and the black pixels will render as 1.0 IOR?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: romullus on 2021-06-16, 10:05:16
No, the moment you assign a map to IOR, its spinner value gets ignored and the map values are read depending on its dynamic range, like it's described in maru's message (https://forum.corona-renderer.com/index.php?topic=31802.msg186485#msg186485) above. So in your example (asuming that we're talking about low dynamic range image), white pixels would represent IOR 1,0 and black pixels woul go for IOR 999
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Yuriy Bochkaryov on 2021-06-16, 12:09:12
we still have an open question - why increasing texture brightness starts to work as an invert for IOR
texture through color correction with RGB 500 - works correctly
texture through color correction with RGB 700 - starts to work as inverted. why?
Why does increasing the brightness of the bitmap change the reflection value of the IOR to inverted?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: romullus on 2021-06-16, 15:12:00
I think that's happening because when you're increasing value intensity, pixels that didn't reach value of 1 yet, are treated by the different set of rules than pixels that are over 1 already. In other words, while pixel's value is increasing in 0-1 range, its represented IOR is decreasing and approaching 1,0, but as soon as that pixel's intensity goes beyond 1, its represented IOR starts increasing and approaching max value, i.e. IOR 999 I always though that this behaviour is global and uniform per map, but it looks that it's being calculated per pixel. I know it sounds complicated and i might be completely wrong, so it would be nice to get confirmation (or denial) from the team.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Yuriy Bochkaryov on 2021-06-17, 11:54:44
The development team is silent and we cannot understand whether this is normal or is it a bug.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: maru on 2021-06-17, 15:31:52
we still have an open question - why increasing texture brightness starts to work as an invert for IOR
texture through color correction with RGB 500 - works correctly
texture through color correction with RGB 700 - starts to work as inverted. why?
Why does increasing the brightness of the bitmap change the reflection value of the IOR to inverted?

Most likely, this is happening exactly because of what I explained in my previous posts:
- if the value is above 1, it is directly applied as IOR (e.g. value 1.5 = IOR 1.5)
- if the value is below 1, it is converted into 1/IOR (e.g. value 0.5 = 1/0.5 = 2)

But to make sure, it would be great to check the specific scene that you are using. Could you please send it to us? The uploader is in my signature below.
Thanks in advance!

I will be sure to look into this myself and in case of any doubts discuss this with the other teams.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: maru on 2021-06-17, 18:18:37
Despite being a non-developer, I am breaking the silence! :)

Please check this video, I hope it clearly explains the behavior we are observing here:
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-06-17, 18:57:24
I needed this, thank you +1
Title: Re: New Corona Physical Material (PBR) playground!
Post by: scionik on 2021-06-17, 21:57:18
Despite being a non-developer, I am breaking the silence! :)

Please check this video, I hope it clearly explains the behavior we are observing here:


Thank you for explaining this case.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Yuriy Bochkaryov on 2021-06-17, 23:14:45
Quote
Despite being a non-developer, I am breaking the silence! :)

Please check this video, I hope it clearly explains the behavior we are observing here:
Thanks for the info.
Now it looks very strange, but you can get used to it.
The main thing is that the developers do not change anything in the future, which will lead to the breakdown of our materials made now on the new physical shader.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: maru on 2021-06-18, 09:23:16
I am still interested in seeing examples of:
- materials that are using IOR textures
- how materials with IOR textures are exported from various commonly used apps - what format are they exported to, what is their bit depth
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-06-18, 09:26:09
Everything from Designer and Painter, Megascans to a lesser extent.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: pokoy on 2021-06-18, 18:49:47
I am still interested in seeing examples of:
- materials that are using IOR textures
- how materials with IOR textures are exported from various commonly used apps - what format are they exported to, what is their bit depth
As for materials with reflection color or IOR textures, basically anything with varying reflection amount on its surface:

- wood
- any sort of stone and minerals (with the exception of those polished for high gloss maybe)
- concrete, especially when mixed with additional stones or gravel etc
- skin (tiny sweat droplets etc)
- metals - almost any metal that's been touched/used will feature oxidation, impurities or stains etc that will result in varying reflection levels
- manmade surfaces that have seen any usage

The more I think about it, the more I'm convinced that almost everything will display varying reflection level. Absolute perfection will look artificial... an exception would be a water surface, maybe :D
Title: Re: New Corona Physical Material (PBR) playground!
Post by: maru on 2021-06-19, 10:36:51
I am still interested in seeing examples of:
- materials that are using IOR textures
- how materials with IOR textures are exported from various commonly used apps - what format are they exported to, what is their bit depth
As for materials with reflection color or IOR textures, basically anything with varying reflection amount on its surface:

- wood
- any sort of stone and minerals (with the exception of those polished for high gloss maybe)
- concrete, especially when mixed with additional stones or gravel etc
- skin (tiny sweat droplets etc)
- metals - almost any metal that's been touched/used will feature oxidation, impurities or stains etc that will result in varying reflection levels
- manmade surfaces that have seen any usage

The more I think about it, the more I'm convinced that almost everything will display varying reflection level. Absolute perfection will look artificial... an exception would be a water surface, maybe :D

Thanks a lot. These examples are awesome. Some of them really opened my eyes. Just a few ideas, of course without discrediting your list:
- some of these effects could be achieved by using Layered Mtl with masks (mixing two or more different Physical Mtls)
- metal with oxidation - could be done with a metalness texture rather than IOR? (maybe?)
- some things (maybe skin with sweat) could be done with uniform IOR and a roughness map rather than IOR map

But even with that said, yes, I see the point.

The question now is:
If you were to create such materials with varying IOR - how would you do it? Procedural textures in 3ds Max? Some textures generated with 3rd party apps? If they were bitmaps, what file format and bit depth would you use?
What would be the simplest, most ideal solution for you?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: MarkusB. on 2021-06-23, 15:32:14
Hi

i am wondering, why isnt the corona converter converting the 3dsmax Physical Material to a Corona Physical Material ? These materials get skipped.

Also is it possible to convert a Corona Physical Material back to a legacy one for backwards compatible reasong? That would be really good. I know you would loose some feature...
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Mohammadreza Mohseni on 2021-06-23, 16:10:58
one of my tests on new physical material. awesome sheen layer.

https://forum.corona-renderer.com/index.php?topic=33608.msg186807#msg186807 (https://forum.corona-renderer.com/index.php?topic=33608.msg186807#msg186807)

Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-06-23, 17:30:06
one of my tests on new physical material. awesome sheen layer.

https://forum.corona-renderer.com/index.php?topic=33608.msg186807#msg186807 (https://forum.corona-renderer.com/index.php?topic=33608.msg186807#msg186807)

Lovely work!
Title: Re: New Corona Physical Material (PBR) playground!
Post by: lupaz on 2021-06-23, 17:35:04
one of my tests on new physical material. awesome sheen layer.

https://forum.corona-renderer.com/index.php?topic=33608.msg186807#msg186807 (https://forum.corona-renderer.com/index.php?topic=33608.msg186807#msg186807)

Really look forward to using the sheen layer. Looks awesome.
If I was the corona team I'd have split the "new features" and added sheen layer as a new feature instead of putting all together as PBR material.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: rowmanns on 2021-06-24, 10:42:28
Hi

i am wondering, why isnt the corona converter converting the 3dsmax Physical Material to a Corona Physical Material ? These materials get skipped.

Also is it possible to convert a Corona Physical Material back to a legacy one for backwards compatible reasong? That would be really good. I know you would loose some feature...
Hi,

3ds Max physical material isn't supported by the converter yet, we are planning on adding support in the future.

We also don't support converting from CoronaPhysicalMaterial to LegacyMtl and it is not planned..

I hope this info helps.

Thanks,

Rowan
Title: Re: New Corona Physical Material (PBR) playground!
Post by: n2graf on 2021-06-29, 02:29:22
Hello, how have you decided the wave values ​​for RGB that are put in the complex IOR that appear here https://coronarenderer.freshdesk.com/support/solutions/articles/12000079075-how-to-use-complex-ior-for -coronaphysicalmtl-? Shouldn't they be equivalent to the ends of the sRGB triangle where Red corresponds to 0.65nm for example? (see link of the image)

https://upload.wikimedia.org/wikipedia/commons/thumb/8/8f/CIExy1931_sRGB.svg/1200px-CIExy1931_sRGB.svg.png

Thanks!
Title: Re: New Corona Physical Material (PBR) playground!
Post by: n2graf on 2021-06-29, 02:31:31
I know that you can pute the values to www.refractiveindex.info but the question is: how do you decided that red belongs to 0,7. Thanks
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-06-29, 10:36:32
Hello, how have you decided the wave values ​​for RGB that are put in the complex IOR that appear here https://coronarenderer.freshdesk.com/support/solutions/articles/12000079075-how-to-use-complex-ior-for -coronaphysicalmtl-? Shouldn't they be equivalent to the ends of the sRGB triangle where Red corresponds to 0.65nm for example? (see link of the image)

https://upload.wikimedia.org/wikipedia/commons/thumb/8/8f/CIExy1931_sRGB.svg/1200px-CIExy1931_sRGB.svg.png

Thanks!

Hi n2graf, please note that Corona is using color space with a wider gamut than sRGB, you will also find that approximations around 0.7-0.55-0.45 can produce a more favoured outcome depending on how much oxidation is introduced on the surface, and the type of metal.

Title: Re: New Corona Physical Material (PBR) playground!
Post by: n2graf on 2021-06-29, 12:42:01
In your freshdesck website you have considered:

0.70 μm for Red, 0,55 μm for Green, 0.45 μm for Blue

But for wideRGB gamut like that:

https://upload.wikimedia.org/wikipedia/commons/1/1d/CIExy1931_AdobeWGRGB.png

Green belongs to 0,52 and blue 0,390. why is there this discrepancy?

Thanks
Title: Re: New Corona Physical Material (PBR) playground!
Post by: romullus on 2021-06-29, 15:08:52
Here's 3 different tables of visible light spectrum that i quickly found on google (there are gazillion of them). Every single of them has slightly different range of wavelength for each colour. As you can guess, there's no single correct value at which we can call the wavelength as "blue", or "red". Values that are chosen in helpdesk by Corona team, lies within widely accepted range. I think there's no need to overthink this.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-07-01, 12:19:05
In your freshdesck website you have considered:

0.70 μm for Red, 0,55 μm for Green, 0.45 μm for Blue

But for wideRGB gamut like that:

https://upload.wikimedia.org/wikipedia/commons/1/1d/CIExy1931_AdobeWGRGB.png

Green belongs to 0,52 and blue 0,390. why is there this discrepancy?

Thanks

I don't believe input values can be absolute, most approximations around the limits of the visible light spectrum will work just fine depending on, as said previously, "preferred visual outcome and on how much oxidation is introduced on the metal's surface" (excluding metal alloys - impure metals - although oxidization implies impurity, but let's just leave it at that).

Let's take the example of Pure Gold (Au) -  Generally, its electrons move at relativistic speeds (especially on its outer surface). The outer surface is responsible for its chemical behaviour and a lot of physical properties, including color. The human eye spectrum varies from wavelengths - approximately 390 nm (blue) to 700 nm (red), gold absorbs a lot of the low wavelengths (blue). So we’re left with the opposite (yellow - towards red when it's pure).

Pure Gold (au) does not get oxidised, hence pure gold should not appear green-ish, it should mostly reflect yellow with a minuscule tint of red. The following comparison showcases exactly just that, Complex IOR of Gold with 0.7-0.55-0.45 against sRGB limited values of 0.61-0.56-0.47: https://corona-renderer.com/comparer/RRnUev (Both outcomes can be described as Gold, but when thinking of recreating Pure Gold we should compensate for corresponding wavelength inputs, in order to remove the greenish tint)

So, to summarize, any approximations between 0.70 μm for Red, 0,55 μm for Green, 0.45 μm for Blue (~ +- within reason) will work great for most pure metals, in some cases, you might want to experiment with different wavelengths. I hope this helps, and it actually makes sense!
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Duron on 2021-07-08, 16:57:10
Today I noticed for the first time a difference in reflections when I changed the roughness IOR from 0.00 to 0.01.

I am not sure if this is already known. So sorry if this is a double post.

Simple reflective plastic material is used with no clear coat.
Everything looks fine at IOR 0.00. Once it goes above 0.01, the reflections change. It reminds of switching the reflection mode in UE4 from nonRT to RT.
Normally this wouldn't bother me at all, but I very often use a value of 0.00 to get softer highlights like from the sun. So almost all my materials are at 0.01. But this example shows why I had problems when creating my physical materials.

Please focus on the BMW badge.

UPDATE:
Did more tests and I can narrow down the cause a bit. The material does reflect an HDR in Dome mode. When the mode is set to Spherical everything is fine.

In Dome mode it seems that the lower hemisphere is displayed as black for materials with a Roughness of >0.01

UPDATE 2:
Updated with new images showing the issue with dome mode.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: pokoy on 2021-07-08, 19:05:40
Reflection glossiness/roughness switches to a different algorithm when used - this was the case with legacy, too. Check and you'll probably see the same thing.

Dome mode - yes, long standing issue, known and reported long ago. The workaround is to add a plane under the model - it can be switched off from camera and reflection/refraction visibility - this should 'fix' the blocky artifacts.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-07-09, 10:12:51
Today I noticed for the first time a difference in reflections when I changed the roughness IOR from 0.00 to 0.01.

I am not sure if this is already known. So sorry if this is a double post.

Simple reflective plastic material is used with no clear coat.
Everything looks fine at IOR 0.00. Once it goes above 0.01, the reflections change. It reminds of switching the reflection mode in UE4 from nonRT to RT.
Normally this wouldn't bother me at all, but I very often use a value of 0.00 to get softer highlights like from the sun. So almost all my materials are at 0.01. But this example shows why I had problems when creating my physical materials.

Please focus on the BMW badge.

UPDATE:
Did more tests and I can narrow down the cause a bit. The material does reflect an HDR in Dome mode. When the mode is set to Spherical everything is fine.

In Dome mode it seems that the lower hemisphere is displayed as black for materials with a Roughness of >0.01

UPDATE 2:
Updated with new images showing the issue with dome mode.

This was a known issue and I believe it's already addressed, unless I am missing something. Which version of Corona DB or RC you are using in these examples?

(Report ID=CRMAX-436)
Dome - (Internal id=311287120)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: muoto on 2021-07-13, 11:10:27
Hello,

How do you deal with flossy refraction (not reflection) with the new PBR material ? In legacymtl, you have the glossiness in the refraction, but it seems to be different in the new pbr materials.

thanks
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Juraj on 2021-07-13, 12:38:19
Hello,

How do you deal with flossy refraction (not reflection) with the new PBR material ? In legacymtl, you have the glossiness in the refraction, but it seems to be different in the new pbr materials.

thanks

Since glossiness/roughness now applies to both, to get different surface treatment requires use of coating. They both kind of simulate different approach to mimicking (usually) glued or different side polish glass panels. Not sure which one gets closer though.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: muoto on 2021-07-13, 13:49:53
So indeed a roughness value, and then a coating works OK (globally very pleased with the results, but it needs some time to get customed to this workflow)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-07-13, 14:07:23
Hello,

How do you deal with flossy refraction (not reflection) with the new PBR material ? In legacymtl, you have the glossiness in the refraction, but it seems to be different in the new pbr materials.

thanks

In terms of physical correctness, the previous implementation allowed for non physically plausible results, you cannot have a single surface that's rough but also highly glossy at the same time.

To achieve a form of coated frosted/etched(even sandblasted) glass you simply have to enable clear coat within CoronaPhysicalMTL, here is an example of a coated/non-coated lamp with base roughness 0.9. : https://corona-renderer.com/comparer/szNYfS

I hope this helps.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Juraj on 2021-07-14, 10:38:01


In terms of physical correctness, the previous implementation allowed for non physically plausible results, you cannot have a single surface that's rough but also highly glossy at the same time.


That reminds me, does it now work if we apply different treatment (through material ID for example) to refractive glass (with real volume/thickness) ? Most frosted glass is simply sandblasted on one side and polished on other (when it's not glued to hide the sand-blasting in middle).

I remember this always created some kind of artifacts.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: muoto on 2021-07-14, 10:55:30
Are there any kind of workflow scripts that automatically import and arrange pbr materials (let's say pbr materials from cc0textures) into the new physicalmaterial from corona ?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: muoto on 2021-07-14, 11:18:27
Can you (it seems not) use a layered mtl with different displacement maps set up in the sub materials ? It seems only the basemtl has the displacement visible, and not the ones from the layered ones. (Would be usefull to mix several materials that have different displacement maps)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: romullus on 2021-07-14, 12:14:19
Are there any kind of workflow scripts that automatically import and arrange pbr materials (let's say pbr materials from cc0textures) into the new physicalmaterial from corona ?

Major PBR texture providers like Megascans, Poliigon and others, have specialized exporters. Also you can find various PBR scripts on scriptspot and in other places. In other words, yes, such tools do exist.

Can you (it seems not) use a layered mtl with different displacement maps set up in the sub materials ? It seems only the basemtl has the displacement visible, and not the ones from the layered ones. (Would be usefull to mix several materials that have different displacement maps)

As you already discovered, displacement only works in base layer of layered material, but that has nothing to do with physical material, it's the same for legacy material as well.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: lupaz on 2021-07-15, 16:52:19
Hi all.
I was at Siger's website and noticed he has a complex fresnel for metals.
I just thought sharing the link here just in case it's helpful for the new material.

https://www.sigerstudio.eu/sigertexmaps-complexfresnel/

Best,
Guido.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-07-15, 18:11:36


In terms of physical correctness, the previous implementation allowed for non physically plausible results, you cannot have a single surface that's rough but also highly glossy at the same time.


That reminds me, does it now work if we apply different treatment (through material ID for example) to refractive glass (with real volume/thickness) ? Most frosted glass is simply sandblasted on one side and polished on other (when it's not glued to hide the sand-blasting in middle).

I remember this always created some kind of artifacts.

I believe it's doable with no issues but, I ll try it out :).
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Neil Cross on 2021-07-29, 11:58:10
Hi all

Is there a way to default roughness mode under advanced options to glossiness?

The only solution iv found is to set up a personal library and save the updated physical material to that library.

Thanks
Neil
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-07-29, 13:20:50
Hi all

Is there a way to default roughness mode under advanced options to glossiness?

The only solution iv found is to set up a personal library and save the updated physical material to that library.

Thanks
Neil

Hi Neil, indeed there is, in your render setup (f10) > system > system settings > material editor, it can be changed as a roughness/glossiness global default.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Neil Cross on 2021-07-29, 13:42:03
Fantastic! Thanks GeorgeK
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Bornix on 2021-08-09, 15:09:43
How about bump in new PBR materials? As I remember in many tutorials there was a rule that correct bump is 0-0,1. 1 is unnatural and too strong in legacy material. Is this "rule" still correct?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-08-09, 19:16:39
How about bump in new PBR materials? As I remember in many tutorials there was a rule that correct bump is 0-0,1. 1 is unnatural and too strong in legacy material. Is this "rule" still correct?

I would really like an official source for this, if possible^
Title: Re: New Corona Physical Material (PBR) playground!
Post by: romullus on 2021-08-09, 20:31:33
Unlike normal maps, bump maps don't have single correct strength value. Strength of 0.01 can be equally as correct as strength 1, it all depends on your texture and the look you are after. I didn't test it myself, but it's pretty unlikely that devs decided to change bump strength for the new PBR material.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Bornix on 2021-08-10, 11:27:55
How about bump in new PBR materials? As I remember in many tutorials there was a rule that correct bump is 0-0,1. 1 is unnatural and too strong in legacy material. Is this "rule" still correct?

I would really like an official source for this, if possible^

I'm also starting to think that I worked at the wrong place where I was taught the wrong methods and habits.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: marchik on 2021-08-10, 14:48:56
I was looking through the built-in library of materials today and I had a question, earlier, before the introduction of the physical shader, we had the opportunity to enable volumetric absorption with scattering after the light passes through the translucent outer shell, this is the pattern for the "Marble White SSS" material.
How to set up such materials now (grape shader, for example), because to enable translucency, we need to check the "thin shell" checkbox, which will automatically disable the ability to adjust volumetric absorption, and so on.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Horse on 2021-08-11, 13:50:41
Where i can find library with new PBR materials... does it exist at all ?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: TomG on 2021-08-11, 13:54:48
Where i can find library with new PBR materials... does it exist at all ?

The Corona Material Library was updated so that some are using the new Physical Material (the ones that are most affected by the change - there wasn't time to convert them all, as mentioned in the blog:
"We’ve also converted some of the previously existing materials to use the new Physical Material in place of the Legacy Material, with the addition of things such as sheen to fabrics, etc. These are the Carpets, Flooring, Concrete, and Ceramic Tiles categories"

https://blog.corona-renderer.com/corona-renderer-7-for-3ds-max-released/
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-08-12, 11:29:54
I was looking through the built-in library of materials today and I had a question, earlier, before the introduction of the physical shader, we had the opportunity to enable volumetric absorption with scattering after the light passes through the translucent outer shell, this is the pattern for the "Marble White SSS" material.
How to set up such materials now (grape shader, for example), because to enable translucency, we need to check the "thin shell" checkbox, which will automatically disable the ability to adjust volumetric absorption, and so on.

I am afraid that's not possible with Coronaphysical mtl, due to the fact that when using ThinShell, refraction is replaced by opacity, and subsurface scattering is replaced by diffuse and translucency.

For marble or porcelain, I would suggest using Volumetric or Subsurface scattering (with the latter being faster to set up and to render). In a case where you still want to employ translucency + volumetrics, you will have to resort to using Coronalegacy mtl.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Bornix on 2021-08-16, 15:22:31
Hi!

It is impossible to use CoronaShadowCatcherMtl with new Physical Glass Material. There is only one solution to use old legacy material and check Thin (no refraction) option. Will you ever improve Shadowcatcher in future?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-08-17, 11:06:40
Hi!

It is impossible to use CoronaShadowCatcherMtl with new Physical Glass Material. There is only one solution to use old legacy material and check Thin (no refraction) option. Will you ever improve Shadowcatcher in future?

Hi, can you please clarify what's the issue, please share some reproduction steps as to why is not working for you.

Thanks,
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-08-17, 19:33:16
Dumb question, but I just want to clarify: 'Base IOR' in CoronaPhysicalMtl is NOT the same as 'Fresnel IOR' in CoronaLegacyMtl, correct?

Also, it's often good practice to pass a reflective metal into a Rayswitch with a pure black materia in the GI slot. To create the pure black material, I would zero out the reflection, but because in the IOR model of CoronaPhysicalMtl there is no reflection spinner, do we just zero out IOR instead to replicate that effect?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: TomG on 2021-08-17, 20:03:17
Depends on what you mean by the same:
- Yes it's the same, it defines the IOR of the reflections. If you are looking for the equivalent to "Fresnel IOR", then this is the one.
- No it's not the same, as it also defines the IOR of refraction (because any real world material only has one IOR affecting both reflection and refraction, not two IORs like the old Legacy Material)
- No it's not the same, as it only goes up to 3 (because real world non-metals don't have an IOR of more than 3, even though the Legacy let you use up to 999, and now the Physical Material has Metal or non-Metal modes)
- No it's not the same as you can't set it for metals, it's preset, unlike in the old Legacy
- And overall in the material, it's not quite the same as there is a Clearcoat layer with its own IOR, which didn't exist in the Legacy Material, so the overall reflectivity of your object may be different than just the Base IOR / Legacy IOR)

Set IOR to 1 for no reflections, yep. You could set Roughness to 1 too but I think that's redundant when IOR is 1. You wouldn't zero out IOR because it doesn't go below 1 :)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Bornix on 2021-08-19, 11:24:06
Hi!

It is impossible to use CoronaShadowCatcherMtl with new Physical Glass Material. There is only one solution to use old legacy material and check Thin (no refraction) option. Will you ever improve Shadowcatcher in future?

Hi, can you please clarify what's the issue, please share some reproduction steps as to why is not working for you.

Thanks,

I made simple scene look:
(https://i.imgur.com/N1DwD4Y.png)
It is impossible to made glass transparent in alpha channel with new physical materials. Shadowcatcher is not working with refraction even with thin shell option set on. Is there any chance that Shadowcatcher would work with refraction in future?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: burnin on 2021-08-19, 11:39:01
Fundamental Physics
Fresnel prevents any surface to be 100% transparent.

PS
Use Legacy Material.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-08-19, 12:34:35
Thanks for the example, I am reporting it as I am unaware if it's expected or not. Regards,

(Report ID=CRMAX-910)

Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-08-19, 15:11:44
off-topic: will the recent webinar be posted to the Corona Renderer YouTube channel?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: TomG on 2021-08-19, 15:25:39
off-topic: will the recent webinar be posted to the Corona Renderer YouTube channel?

Yep, and that should be later today if all goes well :)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-08-25, 06:53:34
Wow, the webinar REALLY helped me better understand the implementation of the clearcoat layer - very cool. In the future, it would be good to see another window with the actual mat graph shown to better understand what is actually being passed into the shader, and why.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-08-25, 10:31:58
Wow, the webinar REALLY helped me better understand the implementation of the clearcoat layer - very cool. In the future, it would be good to see another window with the actual mat graph shown to better understand what is actually being passed into the shader, and why.

Thanks for the feedback Cjwidd, are you referring to any specific examples? I might be able to post node graph here.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: dj_buckley on 2021-08-25, 12:02:42
Wow, the webinar REALLY helped me better understand the implementation of the clearcoat layer - very cool. In the future, it would be good to see another window with the actual mat graph shown to better understand what is actually being passed into the shader, and why.

Thanks for the feedback Cjwidd, are you referring to any specific examples? I might be able to post node graph here.

The clear coat example with the wooden table where it just says 'Combined' in the bottom right.  I'm assuming you've added a mask of sorts in to the clearcoat 'amount' slot, and possibly included a map in the roughness slot too, but it's not clear from the video
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-08-25, 20:15:02
Thanks for the feedback Cjwidd, are you referring to any specific examples? I might be able to post node graph here.

Yes, I am referring to the example with the violin.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-08-26, 12:25:51
Great, due to some changes that happened in the webinar please expect an answer from Nejc Killar, I can also share all states of the violin materials but without textures, I can simply guide you on what to use where, it's nothing really special.

Also, Cjwidd I still owe you the kiwi guide but please give me some time since I cannot share some "secrets" as of yet, but will be able to do so soon ;).

You can also visit the CoronaPhysical Guide here: https://coronarenderer.freshdesk.com/support/solutions/articles/12000079381-corona-physical-material/preview
Title: Re: New Corona Physical Material (PBR) playground!
Post by: Nejc Kilar on 2021-08-26, 13:12:40
Thanks for the feedback Cjwidd, are you referring to any specific examples? I might be able to post node graph here.

Yes, I am referring to the example with the violin.

Hey cjwidd,

First of all let me just say that we are super excited to hear you've enjoyed the webinar and that you've found it useful. That was after all our main purpose :)

I'm attaching the node graph screenshot for the violin scene we've used in the webinar. The full credit goes to GeorgeK for coming up with this one but the reason I'm sharing the graph with you is because we've changed the materials every so slightly for the webinar version.

What changed? Well basically GeorgeK tweaked a couple of other material parameters as well and for the webinar we really wanted to emphasize that even if you leave all the other non-clearcoat related parameters the same you'll still get a completely different look & feel of the wood material as long as you introduce the clearcoat and some absorption.

So the node graph attached is the one from the webinar. Hope you'll find it useful and if you have any questions just let us know.

Oh and again, kudos to GeorgeK for coming up with the scene :)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: TomG on 2021-08-31, 15:35:55
"The clear coat example with the wooden table where it just says 'Combined' in the bottom right"

For the table, all we did is pass the two bump maps through a Mix and feed the result into the Clearcoat bump, thus making it a blend of the two bumps.
Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-09-02, 12:47:14
Thanks for the feedback Cjwidd, are you referring to any specific examples? I might be able to post node graph here.

Yes, I am referring to the example with the violin.

Hi again, I am sharing the aged wood shader of the violin scene, ideally and if all textures were provided, 80% of the current node structure would be deprecated (can simply make this in Quixel mixer and export it), but where's the fun in that. For the most part, it consists of three different node trees, somewhat interconnected due to the Coat damage that should also affect base diffuse.

The exposed parts (un-coated) have increased roughness and low specularity, while the opposite is true for the still coated surfaces. Coat thickness is emulated through the use of Corona Ambient Occlusion where you will get a saturated/darker color on an open surface, while thinner/brighter on edges.  The current setup includes no maps other than 2x free CC0 grunge masks to showcase the effect (replace the wood ones it should look the same rendered, keep saturation and tonality similar to the root), feel free to play around with the violin model: https://data.corona-renderer.com/download/scenes/violin_charles_IX_base_modern.rar

For the varnished version, the setup is quite similar simply grunge masks are significantly toned down, and mostly present in the coating as a form of surface dirt/weather.
An archive of the material can be found here: https://www.dropbox.com/s/wr5qkqt602a7h3j/aged_wood_coating.zip?dl=0
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-09-03, 04:32:57
Also, Cjwidd I still owe you the kiwi guide but please give me some time since I cannot share some "secrets" as of yet, but will be able to do so soon ;).

That's right - I had almost forgotten(!) I'm looking forward to the guide when it becomes available.

I'm attaching the node graph screenshot for the violin scene we've used in the webinar. The full credit goes to GeorgeK for coming up with this one but the reason I'm sharing the graph with you is because we've changed the materials every so slightly for the webinar version.

@GeorgeK That is a beastly material - great work! Thank you for sharing :)
Title: Re: New Corona Physical Material (PBR) playground!
Post by: cjwidd on 2021-10-01, 00:25:59
Being able to do frosted glass on thin shell is so amazing, just wanted to say thanks for that +1
Title: Re: New Corona Physical Material (PBR) playground!
Post by: lupaz on 2021-12-14, 17:12:50
Hi all,

I used sheen for the first time today. I think it works pretty well.
Nice job.

Title: Re: New Corona Physical Material (PBR) playground!
Post by: GeorgeK on 2021-12-16, 16:11:56
Hi all,

I used sheen for the first time today. I think it works pretty well.
Nice job.

Looking good! Is it mapped Sheen?
Title: Re: New Corona Physical Material (PBR) playground!
Post by: lupaz on 2021-12-16, 16:14:33
Hi all,

I used sheen for the first time today. I think it works pretty well.
Nice job.

Looking good! Is it mapped Sheen?

Yup :)