Author Topic: New Corona Physical Material (PBR) playground!  (Read 83960 times)

2021-07-13, 11:10:27
Reply #225

muoto

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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

2021-07-13, 12:38:19
Reply #226

Juraj

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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.
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2021-07-13, 13:49:53
Reply #227

muoto

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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)

2021-07-13, 14:07:23
Reply #228

GeorgeK

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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.
George Karampelas | chaos-corona.com
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2021-07-14, 10:38:01
Reply #229

Juraj

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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.
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2021-07-14, 10:55:30
Reply #230

muoto

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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 ?

2021-07-14, 11:18:27
Reply #231

muoto

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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)

2021-07-14, 12:14:19
Reply #232

romullus

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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.
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2021-07-15, 16:52:19
Reply #233

lupaz

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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.

2021-07-15, 18:11:36
Reply #234

GeorgeK

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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 :).
George Karampelas | chaos-corona.com
Chaos Corona QA Specialist | contact us

2021-07-29, 11:58:10
Reply #235

Neil Cross

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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

2021-07-29, 13:20:50
Reply #236

GeorgeK

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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.
George Karampelas | chaos-corona.com
Chaos Corona QA Specialist | contact us


2021-08-09, 15:09:43
Reply #238

Bornix

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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?

2021-08-09, 19:16:39
Reply #239

cjwidd

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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^