Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] Feature Requests => [Max] Resolved Feature Requests => Topic started by: Eternalnoob on 2014-05-15, 19:46:10

Title: Thin geometry glossiness
Post by: Eternalnoob on 2014-05-15, 19:46:10
Seems that the glossiness parameter have no effect when thin (no refraction) is checked.
Would be nice for a less perfect finish.

(http://s4.postimg.org/t3clzpnst/Slider.jpg)

Result:

(http://s4.postimg.org/dj5896dod/No_gloss_thin.jpg)
Title: Re: Thin geometry glossiness
Post by: Ludvik Koutny on 2014-05-15, 20:07:58
Of course it doesn't work with Thin mode. Refraction glossiness is computed out of refraction depth. The deeper you are in a medium, the blurrier refraction is. If refraction depth is infinitely small, how do you want to compute refraction glossiness?

Are you sure you are not looking for reflection glossiness?
Title: Re: Thin geometry glossiness
Post by: maru on 2014-05-15, 20:22:35
Problem? :>
Title: Re: Thin geometry glossiness
Post by: Eternalnoob on 2014-05-15, 20:47:31
Problem? :>

Yes! How?
I'm felling dumb now.

Update: Ok, i see what you did there. IOR = 1, no thin and that's it.

But it does't work very well for open geometries. I mean something like a plastic bag material.

Title: Re: Thin geometry glossiness
Post by: maru on 2014-05-16, 10:22:37
Yup, ior=1. :)
For open geometry... hmm... can you make it a little thick? For example by adding shell modifier?
Title: Re: Thin geometry glossiness
Post by: Eternalnoob on 2014-05-16, 18:19:18
Yup, ior=1. :)
For open geometry... hmm... can you make it a little thick? For example by adding shell modifier?

Well, maybe it's the only way. I was trying to achieve something like the translucent plastic film from Arch&Design preset, from mental Ray. Something like stretched latex, baloons, things like this.

Thank you.

Title: Re: Thin geometry glossiness
Post by: maru on 2014-05-16, 18:31:43
Maybe use translucency or opacity instead of refraction?

Title: Re: Thin geometry glossiness
Post by: Eternalnoob on 2014-05-16, 19:51:04
Translucency alone doesn't blurs what's behind.

After some tests I got this, using translucency and refraction with glossiness.

(http://s28.postimg.org/5zt4rsgct/shadow.jpg)

It's not bad, but I dunno... The shadows seems wrong, like they should be blurred, and not so sharp. Am I wrong? The light shouldn't be diffused by the translucent material, and produce a blurred shadow for both spheres and itself?

Title: Re: Thin geometry glossiness
Post by: maru on 2014-05-16, 19:52:52
Congratulations, you created toon shader in Corona.
Title: Re: Thin geometry glossiness
Post by: Ondra on 2014-05-16, 19:53:49
this happens because you are using refraction instead of translucency, which is always almost incorrect setup for such effects. The sharp inner shadows will disappear, if you check "caustics" in the material, though.
Title: Re: Thin geometry glossiness
Post by: maru on 2014-05-16, 20:08:29
I don't know what you are trying to achieve but here is my "stretched latex/balloon thing" and it looks like it works fine on geometry with no thickness.
Title: Re: Thin geometry glossiness
Post by: Eternalnoob on 2014-05-16, 20:21:29
Congratulations, you created toon shader in Corona.

Yes, it really looks very unnatural, hehe.

this happens because you are using refraction instead of translucency, which is always almost incorrect setup for such effects. The sharp inner shadows will disappear, if you check "caustics" in the material, though.

Thanks Keymaster. The sharp shadows really disappears, leaving very dark shadows when caustics is checked. Sorry for getting a little offtopic here.

I don't know what you are trying to achieve but here is my "stretched latex/balloon thing" and it looks like it works fine on geometry with no thickness.

Thank you. That's really close to what I was trying to do, a "balloon thing". Thanks for the recipe.