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Nichod (Offline)
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Default 01.05.2012, 15:45

Since I tend to render translucent surfaces that need subsurface light scattering, SSS is a bit more important to me. But I realize that you need to implement the features that the majority of your customers use and that you can't cater to the minority. I'd be happy with a fake SSS effect that might require less modification to the shader system and would result in flexibility for perhaps other effects. It would just require some modifications to how transparency works.

See: http://www.peranders.com/w/index.php...ace_Scattering
   
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Dranix (Offline)
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Default 01.05.2012, 16:06

Yeah, Fake SSS would be a big win already.


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filip c (Offline)
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Default 01.05.2012, 22:40

Quote:
Originally Posted by Martin View Post
Wow, that is a interesting paper. Thanks for letting me know. But for the first I have to work on non-stretching bones.

Bye
Martin

Despite the many wishes that come up (typicly more around every new release ) I'm allways more than happy whith what you've given us an what we can expect! Thanks a lot for showing interest in our suggestions!

I like the fake sss idea tough would be cool if this could be acheeved in cheetah easilly...

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podperson (Offline)
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Default 01.05.2012, 23:35

It looks to me that this fake SSS trick (a) is actually very close to real SSS but doesn't do the lighting calculations in screen space in a pre-render pass to save on computation (i.e. it's conceptually similar to actual SSS, just less efficient) and (b) requires some features which C3D currently lacks in its render pipeline. The "absorption" business is something we simply don't have (and which would be damn useful). Also the way he's blocking light from getting out would seem to require being able to distinguish inner from outer surfaces (which, again, would be damn useful — hmm maybe that we can do via normal calculations).

Given Cheetah 3D's current limitations, this trick is quite similar to this faux SSS trick (except instead of having an absorption setting I used inner geometry to block light transmission beyond a certain point).


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filip c (Offline)
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Default 02.05.2012, 00:05

Quote:
Originally Posted by podperson View Post
It looks to me that this fake SSS trick (a) is actually very close to real SSS but doesn't do the lighting calculations in screen space in a pre-render pass to save on computation (i.e. it's conceptually similar to actual SSS, just less efficient) and (b) requires some features which C3D currently lacks in its render pipeline. The "absorption" business is something we simply don't have (and which would be damn useful). Also the way he's blocking light from getting out would seem to require being able to distinguish inner from outer surfaces (which, again, would be damn useful hmm maybe that we can do via normal calculations).

Given Cheetah 3D's current limitations, this trick is quite similar to this faux SSS trick (except instead of having an absorption setting I used inner geometry to block light transmission beyond a certain point).

I feared it wasn't going to be easy thanks for explaining!
i also like your faux sss solution!
   
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Dranix (Offline)
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Default 02.05.2012, 01:17

Ah well - ZBrush BPR gets better in rapid steps, soon it will be able to replace all uses of external apps for me.


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podperson (Offline)
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Default 02.05.2012, 15:21

Further info on the faux SSS technique linked above. C3D's shader system cannot, at this time, distinguish between back faces and front faces (as I feared) ... in is calculated as though all faces are front-faces. (I don't know how hard this might be to fix, or if we could get an in channel that allowed us to differentiate them for special effects.)

If this worked as expected then the node setup attached would let us render the inside (back) of the test sphere.

If we did have such an ability, among other things we could use the "create a shell for an object, flip it, and make it black" technique for adding outlines when toon-shading. I don't know about blocking light passing through objects the way this works in C4D may simply reflect a property of C4D's render pipeline. The way the blurred transmission trick works depends on light ignoring back faces for some reasons and not others.
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Nichod (Offline)
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Default 30.05.2012, 05:18

I look forward to any updates? *winkwink* And I hope all is well in Martin's world.
   
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Rick82 (Offline)
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Default Great! - 04.06.2012, 03:45

Hi Martin,

Thanks for the sneak peeks at what's ahead. It really is exciting to know what's coming down the road.

Any word on the more "robust" boolean operations you had mentioned previously?

Thanks,

Rick
   
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chikega (Offline)
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Default 11.07.2013, 04:36

SSS would be nice.
   
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