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Ultron

Thickness Shader (SSS) as Alpha Mask

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Problem:

I need to render wool yarn realliy close to the camera. I allready found this free shader as a base:

The yarn is relativly close to the Camera so there is a need to make it fuzzy or blurry on the edges.

The Fresnel shader an Alpha channel doesn´t work cause if the yarn points to the Camera it gets completly invisible

I need a shader based on thickness like SSS but I couldn´t figure out  how to create a clean Black and White mask from the SSS Shader.

 

Question:

How do I make the edges of the yarn transparent based on the POV of The Camera and the Thickness of the Geometry?

 

Thanks a lot

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2 hours ago, Ultron said:

Problem:

I need to render wool yarn realliy close to the camera. I allready found this free shader as a base:

The yarn is relativly close to the Camera so there is a need to make it fuzzy or blurry on the edges.

The Fresnel shader an Alpha channel doesn´t work cause if the yarn points to the Camera it gets completly invisible

I need a shader based on thickness like SSS but I couldn´t figure out  how to create a clean Black and White mask from the SSS Shader.

 

Question:

How do I make the edges of the yarn transparent based on the POV of The Camera and the Thickness of the Geometry?

 

Thanks a lot

having a fresnel in the alpha or transparency won't work because there's also cavities within the sub poly displacement that face away from the camera, so you will always also get transparency in areas where you don't want to have it. your best bet for a smooth fuzzy look is to have a fresnel in the colour channel which is masked by a small noise... then it looks like this: https://gyazo.com/a6fcd8e247390a618e25f37233df921a

 

if you need more i'd suggest to also add some peach fuzz hair  to it...

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  • Peach fuzz hair is a possible Solution but it also add a lot of compexity to the Szene (The yarn is Simulated). Ok Hair on Hair is possible but the render and simulation Time would be greatly increased.

    I would really prefer to solve the Problem on the Shader side.

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  • no I haven´t and - this is a really good Idea!

    THX

     

    edit:

    I tried it but it doesn´t work correct.

    The glow is´nt a Plane color - it gehts multiplied or added. Thats why its nearly impossible to match the color correct and on a white background there is no glow at all. Anyway - it was a nice idea

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  • So there seems to be no solution to solve this on the Shader side. I will now try to solve the problem with the brute force aprouch - hair on hair

     

    Haare_auf_Haaren.jpg

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  • OMG my customer doesn´t like the look of peach hair.

    He "simply" wants soft edges on each individual hair.

     

    - Fresnel doesn´t work on complex structures

    - Rendering individual hairs and blur ther Alpha Mask in AE doesn´t work cause Hairs are sometimes in Front and Back of another Hair at the same time

    - He don´t like Peach hair

    - glow doesn´t match the color of the Hair

     

    Please help me - Its an easy effect which has to be possible. Or isn´t it?

    (Blur edges of overlapping complex Objects)

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    3 hours ago, Ultron said:

    OMG my customer doesn´t like the look of peach hair.

    He "simply" wants soft edges on each individual hair.

     

    - Fresnel doesn´t work on complex structures

    - Rendering individual hairs and blur ther Alpha Mask in AE doesn´t work cause Hairs are sometimes in Front and Back of another Hair at the same time

    - He don´t like Peach hair

    - glow doesn´t match the color of the Hair

     

    Please help me - Its an easy effect which has to be possible. Or isn´t it?

    (Blur edges of overlapping complex Objects)

    A very careful Blur in PS might give what they want.


    Win 7, 8 core PC with 12 Gb RAM 64 Bit

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  • @ Anthony

    Good Idea but its an Animated Charakter. I could blur the Alpha in AE. But if I do so only the outline would be blurred not every individual Objekts outline

     

    @ All

    This Thread is good:

    https://forums.cgsociety.org/t/shader-driven-by-thickness/1584783/15

    Its seems Modo has a Shader wich does what is needed. Does anyone know how to build this:

    Thickness-- Determines how thick or deep an area is and applies the gradient based on the measured depth. The ‘Thickness’ is calculated by a ray being fired inward from the first surface, until the next outward facing surface is encountered (the backside).

    This Thickness Shader i could plug in to the Transperncy of the Shader to get blurred edges

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  • Even it was a bit embarrassing to me: I said this to the customer now. I think the look of peach hair is better than blurred edges.

    Anyway the customer is allways the king and I hope I can convince him.

     

     

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