Tips for speeding up water renders?

[domdib]

Does anyone have any thoughts? My current scene has some water in it, and I've tried messing around with various settings in the shader, but nothing makes a substantial difference.

[cyphyr]

The thing that really slows down water is if your viewing it through a cloud layer, that really slows it down.
richard

[domdib]

Fortunately, I'm not, but it's still pretty slow   

[neuspadrin]

making the lake object as small as possible helps.  if most of it is blocked behind terrain and you just have a small lake going on, just make it very small just so it can go through its areas.

Works well unless you got a scene where its looking out on an ocean

[Henry Blewer]

The default water shader uses a huge disc. There is a size input. Click on the center of the place you want your water and copy the coordinates. Now paste these into the translate input of the water shader. Now the disc can be made just big enough so the 'pond' gets water.

[PutzOMatic]

Crap!
I'm using a dense RealFlow mesh ( already slow to render )
with a water texture and there's clouds all over the place.  
It looks nice, but man is it slooooooowwwwwwwwwww!!!
I can render it in 2-3% strips but then there's the whole
GI seam problem. I tried using overlapping strips so I could
edit out the seams, but you can tell it's been patched up so to speak.

[dandelO]

You might try this... http://forums.planetside.co.uk/index.php?topic=8793.0

If there's a lot of water 'underground' that you don't need to render.

[Oshyan]

Putz, do you have any terrain in your scene, or is it all the RealFlow mesh (object) and clouds?

- Oshyan

[PutzOMatic]

It's all imported geometry.
I just tried the "Ray trace objects" option and it seems to have sped it up quite a bit.

Also, the processors/threads seam to be assigned to certain sized chunks of the image.
I always end up with 1 processor at the end chewing away on a huge amount of the scene
making it take 10 times longer to render than if all the processors were kept busy until the scene was finished.
Is this just a technical limitation of the rendering engine or is it possible to optimize it better in a future release?

[Oshyan]

Cool scene. Raytrace Objects will definitely help, as you noticed. If you have no *terrain* in your scene (Terragen terrain) and it's all objects and TG sky/clouds, you might try Raytrace Everything, and turn AA down to say 3 or 4, set Cloud Samples by Quality of 1, and Atmosphere samples to maybe 32 or 48.

The size of the render tiles varies with the AA setting. Higher AA = smaller tiles. This could potentially be controlled separately (and manually) in the future, but ideally the remaining tile(s) would just be subdivided and rendered with all cores until the image was finished.

- Oshyan

[PutzOMatic]

Cool, thanks.