Transparent water?

Announcements, requests and support regarding the Cinema 4D exporter
Post Reply
7 posts • Page 1 of 1
stackbabbler
Posts: 8
Joined: Sat Dec 17, 2016 3:24 am

Transparent water?

Post by stackbabbler » Fri Feb 24, 2017 10:10 am

I've tried a lot of different settings now, but it seems I get black water no matter what I try so I must be doing something fundamentally wrong. I'm rendering with BiDir MLT. I've tried almost every water material in the database, turning on/off SSS although I'm not sure what it does. This is the material I'm currently trying: http://www.indigorenderer.com/materials/materials/31. I've tried exporting the scene in mm, cm, m, km, user:25, user:0.025 and user:0.0025, (in c4d the Project Scale is set to 0.025 m). I've tried setting the texture length U/V from 0.001% to 10000%. I've tried cubes from 0,01 m thickness to 10 m thickness.

Before I waste any more time, I thought I should ask and see if there's a simple solution.

Does the amount of faces/subdivision of the water cube factor in at all?
Does the water become more transparent the more samples per pixel? I've only tried around 500 spp.

I'm using the most updated Indigo 4 with C4D R17. Thanks.
Attachments
quickrender54.jpg

User avatar
thesquirell
Posts: 382
Joined: Fri Aug 29, 2014 3:49 am
Location: Novi Sad, Serbia

Re: Transparent water?

Post by thesquirell » Fri Feb 24, 2017 11:48 am

In order to get good results with water, good modeling is needed. Accurate, that is. That means that your base, "under" the water surface, must be a solid, or a plane with normals pointing upwards. Also, the water volume must engulf the whole volume beneath the surface, with no gaps, so it can trace absorption and caustics correctly. The number of faces of the water surface and the topology will determine caustic effect on the bottom(ground), and the edges(ex.pool). At first, you will see a colored surface, transparent-more or less, depending on your absorption amount, but if you let it sample more and more, you will start to see the caustics.

If you are still having troubles, you can send us your scene, and we can model it for you, so you can reverse engineer it, and learn

stackbabbler
Posts: 8
Joined: Sat Dec 17, 2016 3:24 am

Re: Transparent water?

Post by stackbabbler » Fri Feb 24, 2017 7:41 pm

Thank you for your response. I checked the normals and they are all pointing up, and the cube is larger than the plane. It would be great if someone could have a look. Here's a stripped scene where I deleted most textures and object that weren't relevant:

https://drive.google.com/file/d/0B8gPw0 ... sp=sharing

Sorry for it being so messy. Any other comments on my general indigo settings would be appreciated.

Thanks.

User avatar
thesquirell
Posts: 382
Joined: Fri Aug 29, 2014 3:49 am
Location: Novi Sad, Serbia

Re: Transparent water?

Post by thesquirell » Sat Feb 25, 2017 12:30 am

So, after looking at your scene, and extracting the water volume and surface, setting the scale to cm, everything looks normal. My suggestion to you is to model and render in the real scale reference, that way you can keep a track on everything, especially concerning the mediums and absorption amounts.
Attachments
scnshot1.png

User avatar
OnoSendai
Developer
Posts: 6179
Joined: Sat May 20, 2006 6:16 pm
Location: Newcastle upon Tyne, UK
Contact:

Re: Transparent water?

Post by OnoSendai » Sat Feb 25, 2017 12:32 am

By the way, the fast way to render this, would be to use a phong material with high exponent/low roughness for the whole ground. Then set fresnel_scale to zero outside the water region, and to one inside the water region.

stackbabbler
Posts: 8
Joined: Sat Dec 17, 2016 3:24 am

Re: Transparent water?

Post by stackbabbler » Sat Feb 25, 2017 2:49 am

Hmm... I tried making a new scene with both Project Scale and Indigo export scale set to cm. There's only a ground, water, light and camera in the scene, but the water is still not transparent at all. Could someone have a look at this specific scene? Nevermind the two holes in the ground plane.

https://drive.google.com/open?id=0B8gPw ... DV2emI0NXM
Attachments
quickrender57b.jpg

User avatar
thesquirell
Posts: 382
Joined: Fri Aug 29, 2014 3:49 am
Location: Novi Sad, Serbia

Re: Transparent water?

Post by thesquirell » Sat Feb 25, 2017 5:53 am

This particular material is very expensive to render, especially with SSS. Everything is fine, it just takes more time to render it. You can see even in your screenshot that the caustics are beginning to form on the ground (those green dots). Try using a normal specular materials without any sss, just the absorption.

Post Reply
7 posts • Page 1 of 1

Who is online

Users browsing this forum: No registered users and 3 guests