PBR Material Support with NO Fuss

I'm noticing that the preview for the tiles on the freepbr.com site is a little more shiny/glossy. see attached. Curious if the PBR shader has fresnel built in?

Cheetah3D uses the GGX BRDF + Fresnel for specular reflections like described in the Disney paper.

It's not really possible to compare these images since Cheetah3D uses a completely different light setup. And the light setup have a massive impact on the appearance of the surface.
 
Here is the screenshot of the PBR shader. I've also added support for DirectX style Normal maps. They are quite popular these days.
 

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Wow! This really looks excellent. It seems like you've really been thorough.
:icon_thumbup:

--shift studio.
 
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Just curious how alpha channels and transparency will be accommodated?

Thanks, Shift Studio.

... or maybe I should just wait and see?
 
Just curious how alpha channels and transparency will be accommodated?

I'm not sure about that. Since the classical pbr shader is a pure reflection model (no transmission) there is no obvious answer to that question. It's pretty open to the developer how it's integrated. But for rendering foliage there should be at least some sort of stencil functionality for the alpha channel.
 
This will definitely be another great addition like soft lights with profiles.
I agree on alpha channel support being useful (just a checkbox maybe).
Not being familiar with the Disney thing I'd like to ask for a link to some paper where the new properties are explained, to get an idea what to do when adjusting them.
Also helpful would be some new materials (metals, plastics, etc) based on this new shader in the native Cheetah material repository.
 
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I'm not sure about that. Since the classical pbr shader is a pure reflection model (no transmission) there is no obvious answer to that question. It's pretty open to the developer how it's integrated. But for rendering foliage there should be at least some sort of stencil functionality for the alpha channel.

I agree, especially (but not only) for foliage.
Yesterday I was looking at 3DScans like >> https://www.textures.com/download/3dscans0335/132912, and similar. They have albedo, alpha, normal, roughness and translucency texture maps, and I was wonder how I could deal with alpha and translucency channels.
Note: This isn't project specific, so I don't need anybody to make a work-around with existing c3d material shaders :wink:

@misoversaturated, I recently skimmed over these, and think you may be interested>>
https://www.marmoset.co/posts/physically-based-rendering-and-you-can-too/
https://www.marmoset.co/posts/basic-theory-of-physically-based-rendering/
I know its not the disney white paper but...

Thanks, Shift Studio.
 
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Do you really want a separate alpha channel for foliage? Why? :p

Cheers
Frank

umm, not sure what you mean? I'm talking about when you make a material and apply it to a plane, and use transparency to 'hide' the non-leaf areas of the plane. Is that an outdated practise?

--shift studio.
 
Here are some interesting links about the PBR shader workflow how it is used today in most big game engines and also in an increasing number of 3D content creation apps.

And easy start is offers by the creators of Substance Painter (it's quite popular in the game industry to create PBR textures):

https://www.allegorithmic.com/pbr-guide

Here is the very popular paper of the "Principled" PBR shader by Disney:

Physically-Based Shading at Disney

Here is a excellent paper how UE4 does pbr shading:

Real Shading in Unreal Engine 4

Happy reading.:smile:
 
Sorry, I wasn't being clear.
I was thinking something akin to this (see screengrab) in the PBR Shader.

I want to stays as close to Disneys Principled and the UE4 pbr shaders which doesn't offer the "Transparency" properties. I want to keep it lean and fast.

I don't want to create another Uber shader like Cheetah3Ds Material shader.

pbr texture sets usually don't have translucency textures. Your example is actually the first I've seen.
 
@Martin - got it. Those 3D scan textures were the first I've seen too.

just for interests' sake, it looks like Substance Painter offers a shader called 'pbr-rough-metal-with-alpha-blending'. Here is a link to a youtube video >> https://youtu.be/jQjLnoZClB8

Looking forward to the lean/fast PBR!

--shift studio.
 
But for rendering foliage there should be at least some sort of stencil functionality for the alpha channel.

Thinking about that, PBR materials are not really meant for foliage, that needs a translucent shader that turns the diffuse light of one side into emissive light from the other side of a polygon.

With this we could render leaves, paper, cloth and plastic sheets with lights behind.
And that would need alpha channel support and also a reflective component.

But the Disney thing I could use without alpha map.

Thanks for the links btw!
 
Testing the PBR shader

I converted some of the default materials in C3D (and those created for the tutorial models) to PBR.
Makes a difference when used throughout the scene.

All PBR, except water and glass.

HDRI light only.
 

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