thin SSS

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hi all

i'm looking for a mantra solution for thin SSS, also known as single-sheet sss

ala maxwell 2.0 and fryrender…

for shading things like leaves and paper.

i've seen some nice sss shaders in the exchange but all of them require objects with thickness or volume. and if i have, say, a million instanced leaves, i'd rather keep the geometry as light as possible.

any ideas?

-edit-

a really nice reference and explanation:
http://think.maxwellrender.com/creating_a_single_sided_translucent_material-213.html [think.maxwellrender.com]

it's basically scattering + transmission
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*update*

axis sss is actually working pretty well, i think it's been improved since i last tried it…

however it's still a hack, light doesn't truly pass through the object… would probably need a PBR shader for this it's fine in most cases but if one plane casts shadows onto another it's not picked up properly…

these images should show you what i mean.

simple scene, one arealight above (ray shadows) and one point light below. first image, point light has no shadows… second it has ray shadows turned on, notice how it totally kills all the “transmission” when it should just lessen it…

shadows off (see the red light on the sphere as well, an artifact because of no shadows)


shadows on
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Hello Artzor,

Were you able to get AXIS SSS to work in Houdini 10?
After installing it the menu doesn't show in the digital asset.

Thanks,

Frank
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Are you in the right context for calling in the shader?
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probbins
Are you in the right context for calling in the shader?


Hello,

LOL! Found it!

Thanks,


Frank
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hi all
i'm looking for a mantra solution for thin SSS, also known as single-sheet sss

Thin translucence like this is pretty easy to pull off. You simply flip the normal around and call diffuse() on the backside of your surface. Then all you need to do is sum the result of that (probably scaled down) with the rest of your lighting.

Gl dude.

-b
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Ive done a hack to fake this stuff before now in Maya. I basically have 2 textures a back lit leaf version and the basic leaf texture , then I blend the textures based on how the normal / camera direction.

rob
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