Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: naeq on 2014-08-21, 10:16:32

Title: Refraction Issue (dark shadows)
Post by: naeq on 2014-08-21, 10:16:32

Hello,

Here's problem: When I've add a corona light (or light obiect) behind a camera, drops on bottle have dark shadows.
Caustic is enabled. That problem exist even when I switch cast shadows off.

I just wondering, it's a bug or model/scene issue?

(http://i.imgur.com/9KctXMF.jpg)

Material:

(http://i.imgur.com/WF0diz7.png)

Title: Re: Refraction Issue (dark shadows)
Post by: maru on 2014-08-21, 10:31:19

That's because you are using caustics. When you enable them, refractive objects cast shadows and then caustics are computed. Caustics are a bit painful for Corona right now so I would suggest turning them off, at least for the drop objects. Do you really need them? Caustics on glass?

Title: Re: Refraction Issue (dark shadows)
Post by: romullus on 2014-08-21, 10:31:46

1. caustics don't work very well with progressive engine for now. You may want to switch to Bdir/VCM for caustics, but that may give you even more headache, because VCM has rather limited supported features set :]
2. it looks like your drops aren't correctly modeled and/or scattered.

edit: Damn ninjas :]

Title: Re: Refraction Issue (dark shadows)
Post by: naeq on 2014-08-21, 10:49:33

Thanks for fast reply! See what happens, when I switch off caustics:

(http://i.imgur.com/0eSRPK4.jpg)

Title: Re: Refraction Issue (dark shadows)
Post by: naeq on 2014-08-21, 11:06:38

Bidir / VCM after 15 mins and 1716 passes (?)
Seems like they're gonna render correctly, but I don't wanna wait few days :)

Edit:
romullus you're right, I didn't make a surface tension and mesh blob :)

(http://i.imgur.com/cYaXQNn.jpg)