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SSS as Translucent Map


detbear

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Hey Everyone.

 

I was watching a demonstration on Marmoset Toolbag where game professionals drive SSS in their characters

using a Translucency Map. Basically the "Greyscale" map controls how much or how little SSS effects specific areas.

That way, you can have more SSS in areas like ear lobes, etc.

 

I wonder if A:M could do this via one of the Map types in the decal selections. OR if a new Map type could be created

to control this in A:M.

 

Kevin

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I haven't check out the link yet but decals do effect the SSS in A:M.
I'd have to check again to see what effect patch images might have but varying the color on layered patch images should also have an interesting effect.

While I know there is some difference to the current approaches when I first saw the idea of SSS being controlled by image maps my thought was... I think A:M can already do that. It's well worth the look into what effect various maps can have.

Thanks for the video link. I'll check it out.

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Hey Rodney,

 

I was thinking at first that there might be a current map type that could be used in this manner. But on a quick try,

I couldn't find one that worked. HOWEVER, I still think it may somehow be possible.

 

By making changes in the image(Via photoshop, etc.) you could control the SSS strength and placement.

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That looks cool... realtime render!

 

A:M's SSS feature is working quite nicely nowadays, and seems a swift render feature as well...

 

So- you are saying can we add a 'translucency map' to the decal map types? Interesting... translucency in A:M is one of those features I never really got a grasp of as to what it does or can do. I've been toying with it and SSS together... would the ambience intensity map type do similar with the appropriate color?

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One path I see is to apply the grayscale map that indicates how strong the SSS effect should be, render with that as a greyscale image (flat shaded, of course) and use that to composite a SSS render with a non-SSS render and using the greymap to control how much of the SSS render shows thru vs. the non-SSS render.

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One thing to keep in mind, and this SSS workaround does not consider... is that SSS is a light-driven effect, meaning that a strong backlight is needed in order for it to show-up. Good examples of SSS are a flickering candle where you can see the light absorbing and diminishing thru the wax... or a flashlight held up to your hand, where you can see the light illuminate thru the thinner parts of your flesh. Element 3D, which has a nice SSS effect, requires the usage of either a backight/rimlight or an HDR optimized for SSS, and I have found the same holds true in A:M- where I place a strong (200%ish) sun or bulb light behind or rim-lighting the character I want an SSS effect on. You can place the light in a light list so it only effects the character and not the entire scene should you want.

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I think Robert is correct that the main effect of a "Masking" map would hopefully be able to

allow where the SSS actually shows through on a model. So that SSS would show up in the lighter places.

And you could blur the greyscale map to feather the edges.

 

I don't know if the SSS in A:M could be masked like this via a decal map though?

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I don't know if the SSS in A:M could be masked like this via a decal map though?

currently - No.

 

A 100% decal does not necessarily hide the SSS effect. Darker decal colors might make it less noticeable

 

You might try playing with a gradient material and varying the SSS between the attributes. Yes I will.

 

EDIT: just tried controlling effect with a gradient - does not seem to be very controllable wrt to SSS. Gradient does effect somewhat if you want to limit control to % of edge (like a fake rimlight) - but it's not easily tweakable.

Edited by NancyGormezano
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I think Robert is correct that the main effect of a "Masking" map would hopefully be able to

allow where the SSS actually shows through on a model. So that SSS would show up in the lighter places.

And you could blur the greyscale map to feather the edges.

 

I don't know if the SSS in A:M could be masked like this via a decal map though?

 

This isn't something that can be done in one pass... within A:M.

 

It requires compositing of three passes... the SSS pass, the non-SSS pass and the pass that shows the greyscale SSS-intensity pass. The additional render time for the SSS-intensity pass would be negligible.

 

If someone wants to post me a simple SSS PRJ I can show how it's done. Something with an obvious SSS case like backlit ears.

 

 

 

 

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I don't know if the mask on the model is needed, since SSS is self-cancelling. You could render your normal pass, then render a black pass with the SSS as white and composite it additively in post- being able to crunch, blur, and color as you see fit. SSS only shows up on groups where it is activated and only shows in the thinner geometries.

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