Wetting coloration and black fringe edges

[Deflaminis]

Hello, thanks for looking in. I have a couple questions about some coloration and edging on some of the water on some rocks.

I have a link here to a test movie. The river starts off with an initial fill up based on geometry (thanks for the tips on that previously), and I'm really happy with how easy it was the setup and get working well. However, I was wondering what I can do about 2 things in this movie. I tried to search but maybe I was searching for the wrong key words. It doesn't start happening until about half way through.
https://youtu.be/_oxOku1JhCk

1) Is there a way to make 'wet' geometry darker? I'm not really sure how to approach it. I would expect the river bank and rocks to be a bit darker where the water has hit or flows over. Wetting is on, but it's hard to tell.

2) I have some weird black edges on the water as it splashes over the rocks. I'm using an HDRI to light this and it affects diffuse, reflections/spec, and refractions. However it seems that the edges are black sometimes as if I was just reflecting my black background here. (Hope I'm making sense.) Or, maybe it's something else?

I've attached the file for what it's worth. Thanks for any light you can shed on the situation. EDIT: If it's worth mentioning, I'm using the progressive renderer in 3.4.

Best Regards,
AJ

River_test01.zip

[flipbook]

Evening!

1: Sim using wet particles being output. Load the wet particles via a particle texture map and then use that map as a mask in a blend material... apply this to the rocks.

2: are your reflection/refraction depths too low?

Looking good though.

[Deflaminis]

Hi, thanks for the feedback and kind words!

I'll look into the wet particles here tonight, thank you for the idea! EDIT: Currently my output particles are set to "liquid", do I need to resim entirely if I change it to 'wetmap' or should I use the resimulation? Thanks!

Regarding the depth, I tried setting it to 10/10 but same issue. I turned the reflective exit color to green and the refractive exit color to red but they still render black which leads me to believe that it's something else, unless I'm just having a brain fog. EDIT: I also tried setting my environment reflection/refraction color to blue to see if that had an effect on those black edges but... no luck.

Thank you so much for the wet particle mask idea! Never used it but will give it a go!

Best,
AJ

[Deflaminis]

As a follow up question to the particle texture map, which channel should I be using for the mask? I must be doing something wrong as none of them seem to affect it correctly. I'm using a vrayblendmtl. (Or do I need the RGB channel on as well?) Thanks for any tips!

[Svetlin.Nikolov]

Hey,

You need another texmap - it's the Phoenix Particle Texture - it basically takes a particle system and converts it into a grayscale mask that you can use for blending between a wet and a dry material. You should also watch out if you need to adjust the particle print size there - you will see in the produced map whether the particles are too small or too big. Basically that should be it.

Not sure about what really looks like weird refractions, though. We'll have a look...

Cheers!

[Deflaminis]

Thank you very much for the tips, I will take some time tomorrow and try it out!

Where would I plug that in?

[flipbook]

Just use it as a mask in a blend material, it outputs a white map for where the wetmap particles are. If you don't have wetmap particles then you may be able to get them via a resimulation (I dont know, worth a try) as I just output them by default as usually come in handy later on

[Deflaminis]

Fantastic, thank you!

[Ivaylo Katev]

you can use the interactive ocean scene as guide how to render the material wetting, search in the image section for the thread