VRay Next GPU + Water

[D3Pixel]

Hi

Are there any tricks on getting a water material with GPU rendering using Vray GPU Next?

I specifically need an ocean water shader that I dive under near a structure that goes to the sea bed so translucency is required.

The rest of the project uses VRay GPU so switching back to CPU would be a real issue. Any help would be much appreciated.

Thanks
PS. Tried a VRayFastSS2 with a VRay Blend without any success getting transparency working. VRayMtl + GPU does not support translucency.

[chadstevens]

I've created a small scene with a water material in Vray GPU, it seems to work just fine.

It's 3ds max 2018 and 2019, if you need an earlier file, let me know.

[D3Pixel]

Hi Chad.

Thanks for the reply.

As I mentioned I need translucency in the water and the VRayMtl does not support that.

I need to show objects submerged in the water. Dirty water etc.

Cheers
Geoff

[D3Pixel]

Anybody?
Unless somebody has a solution to a "translucent" ocean shader using VRay Next GPU I will have to switch my project over to RedShift, Obviously that will be a hassle but at least it works on the GPU over there.

[MANUEL_MOUSIOL]

Why don't you just use refraction? That's how water works, no? Or am I missing something..

[savage309]

You can use fog gizmo of fastsss2.
If it doesn’t work for you for some reason, please send a scene.

Best,
Blago.

[D3Pixel]

>>Why don't you just use refraction? That's how water works, no? Or am I missing something

For pure clear water just refraction is fine but this is ocean water. It needs a surface falloff which you usually achieve using translucency as the camera will be high above the water, then dive into it, then sink to the ocean floor.

You can use fog gizmo of fastsss2.
If it doesn’t work for you for some reason, please send a scene.
Best,
Blago.

Thanks, time permitting I will try that again this evening. A third option is to simulate the shot in post with z-depth passes, might be less complicated than trying to get SSS looking like ocean water from above and within it.

[chadstevens]

You could try using Vray environment fog for the ocean

[MANUEL_MOUSIOL]

>>Why don't you just use refraction? That's how water works, no? Or am I missing something

For pure clear water just refraction is fine but this is ocean water. It needs a surface falloff which you usually achieve using translucency as the camera will be high above the water, then dive into it, then sink to the ocean floor.

Mmh, if you have time, could you please explain further? Or show some example.. I don't quite grasp the concept yet.

[chadstevens]

See attached, note that you need to change the refraction of the water once your camera is below in order for it too look correct, I believe it's 0.75.

Cheers.

[D3Pixel]

Mmh, if you have time, could you please explain further? Or show some example.. I don't quite grasp the concept yet.

My scene requires a 1 to 2 mile stretch of sea water, starting from land I travel (at an altitude of 400 feet) to where the water is about 100 feet deep to a structure there, then I descend vertically into the depths to show the sea bed and the underwater part of the structure.

I found these samples on the net that show depth falloff with an ocean shader.

This one is done in Blender Cycles
https://www.artstation.com/artwork/eogeD

And this one
https://www.artstation.com/artwork/BewlA

Cryengine does a great job too.
https://forums.unrealengine.com/file...7&d=1457279179

If possible I need the same water to look great while inside the volume too. If not I will break the outside vs inside the water using post effects, fog etc.. This bit is much simpler than outside the water looking into it's depths.
e.g.
http://www.costaricantimes.com/wp-co...experience.jpg

[D3Pixel]

See attached, note that you need to change the refraction of the water once your camera is below in order for it too look correct, I believe it's 0.75.

Cheers.

Thank you for the examples! PLEASE tell me those are rendered on the GPU as I have not managed to create that depth effect with VRay Next GPU.

[Ihno]

note that you need to change the refraction of the water once your camera is below in order for it too look correct, I believe it's 0.75.

I'd not do that.. Its phoenix right? There is an underwater goggles checkbox.
I unchecked the water material isn't applied to the lens of the camera any more once its below the waves. This will also kill the fog from beneath the surface so you'd have to find a solution for this like environment fog or something but changing the materials IOR to an unrealistic value seems like the wrong way.
To leave it on is physically correct. Unless you have some kind of Submarine cockpit in front of the camera and you're actually looking out from the inside.

[D3Pixel]

chadstevens Is that using Phoenix FD? That is CPU rendering only? If so then I am back to trying the option that savage309 suggested.

[chadstevens]

D3Pixel Yes it's using the PhoenixFD displacement map not the simulation and it does work with the GPU as that's what those images were rendered with. It's using Vray environment fog as well.