Is there such a thing as Stochastic Scratches?

[stevejjd]

Hi Guys,

I'm trying to make a car paint shader with fine "Spiderweb scratches". I also want to make scratched metals.

I saw that there is a Stochastic Flakes Mtl in Vray. I wanted to ask if there is a Stochastic Scratches texture map?

I would love to make high res normal maps for scratches.

Is chaos group interested in procedural texture nodes that generate high resolution Normal maps for things like glints, fine scratches n stuff?

Steve ~

[Raven]

Have you tried sigerscratches?

https://www.sigershop.eu/free-3ds-ma...igerscratches/

[super gnu]

i guess i know the answer, but will those Siger maps work with GPU? the scratches one looks v useful.

[Raven]

You guessed correctly, they are not supported by RT.

[stevejjd]

This is fantastic

[PIXELBOX_SRO]

http://viscorbel.com/microscratches-...vray-tutorial/

[stevejjd]

PIXELBOX_SRO - Hell yes!

Instead of using so many materials in the shader, I may try using the blend normal in substance designer.

https://support.allegorithmic.com/do...C/Normal+Blend

[Ihno]

This tutorial is pre vray bumpmtl. It can help to simplify that setup.
Also use rens MixNormalMap osl if you want to mix different normal maps like some with strate and some with circular scratches.
http://www.rensheeren.com/
But all in all it's a pretty fiddly setup and more some kind of workaround. It might not work in every scene.
I believe no one on the rendering coding side found a good solution for this yet.

[stevejjd]

https://www.youtube.com/watch?v=MR5ochhiqqc

Im gonna try using substance painter instead of OSL. My 3ds max crashes a lot with OSL.

Ill generate a few differnrt scratch normal maps and combine them in Designer

[stevejjd]

That OSL can only mix 2 Normal maps and it crashes 3ds max a lot.

[Ihno]

you can stack multiple of them

That substance scrach generator looks very good

[kosso_olli]

This was done with some scratch texture, basically the white scratches on black background used as a bump map.
I don't understand the setup in the Viscorbel tutorial, it looks way to complicated to me.

[joconnell]

That looks stunning Olli. Lensing and glints / glare is lovely. In camera dof?

[stevejjd]

Thanks for the hint about Scratches Bump maps and the Siger scratch maps

Have a look at this link;

https://renderman.pixar.com/stories/cars-3

the Pixar car shader. The micro scratches are done with normal maps and a Bump Roughness BRDF. From what I understand, The shader will use the normal map in close shots and as the distance from camera increases, the shader will blend between using the normal map to relying on the roughness. This is because sampling the normal map takes ages.

[kosso_olli]

That looks stunning Olli. Lensing and glints / glare is lovely. In camera dof?

Yes. In-camera DOF, together with Bloom and Glare from a filter image. Someone here on the forum provided the filter image, I think it was you.

Here are some more from a different project.