Water material

Hi,

Although this is only using SuperSpray, I've been playing with trying to get a nice water shader without use of any commercial plugins.

http://www.stephendgreen.pwp.blueyo...water_spray.wmv

It uses cubes spinning at high speed (a few frames for a complete spin with some variation - Brandon Davis' Intermedia Case Studie put me on that track), using object motion blur and a little of John Burnetts Motion blur render effect on top to smooth the more obvious stepping.

There is a bit of the basic translucency shader to give a bit of light, and a small sample of water texture face mapped to the cubes. And very bright specular...

It seems to give quite a nice look of foamy spraying water.

It will be interesting to see how it works with different motion and scale.

Cheers

Steve

Looks great Steve, a little fast, but it looks great Would be interesting to see if it still works with something a bit slower.

Hi,

Thanks, it should be OK - I think the fast rotation is giving the nice blobby feel without the overhead of metaparticles. Slowing down the actual motion of the particles shouldn't affect the look too much (fingers crossed).

I'll try slowing it down, see if it still holds up.

Cheers,

Steve

Not much slower, but more of a waterfall thing going on...

http://www.stephendgreen.pwp.blueyo...k/waterfall.wmv

Still seems to work, although I'd probably add some geometry to bulk it out, and maybe some atmospherics for the really fine mist.

I need to have a look at some reference footage.

- Steve

I think it looks really good

Out of curiosity, how many particles were required for that to look right?

Hi,

thanks - quite a few , on the first one it was a thousand or so in the rate setting for Superspray. I just kept upping it until it looked OK. I guess you could get away with less if you had some geometry blocking out some of the more solid areas.

It's a bit of a double-edged sword unfortunately, object motion blur eats up more memory.

Mental Ray motion blur also seems to run out of memory sooner than IMB.

Cheers

Steve

That looks pretty promising Steve, and especially that waterfall looks awesome. Have to find something about making the upper edge less furry, but it sure has potential

Hi,

thanks, yeah I need to get hold of some good nature DVDs for reference.

I guess at the top it would be pretty flat unless there were some rocks to break against, maybe some just some displaced raytraced geometry for a thin curtain of water.

I might give Mental Ray a try for that - I could try the scanline raytracer, but I'm not sure how much quicker MR would be.

Brazil doesn't have 3D motion blur in v1, which rules out using that spinning cube trick for the particles, and VRay has problems with Pflow as well I think.

Cheers

Steve

Vray is working on it in the new release though.
Vray:: Motion blur for PFlow systems

GettyImages.com has some good material btw, check out this video.
I guess it's pretty important to spawn a lot of small particles on the way to create the dust/steam or whatever that's called. And when you look at the top edge, you're not far off at all!

Yeah, 1.5 seems to have been on the cards forever - hopefully there'll be some news at Siggraph.

I think maybe a duplicate particle system with a short lifespan and smaller particles would work for the edge.

I want to have a look at getting the nice arcs of water on that stock footage. Not sure if the best way is just to ramp the birth up and down, or to use space warps.

I guess it's similar to that Revenge of the Sith lava spray that was posted a while back.


Cheers

Steve

GR8 effect there, i like experirmenting with the Particles from time to time. Must say that 2nd one makes me wanna go swimming. Sort of thing u want as a screen saver!

Like ive said in another post, theres no real water system in Max which is a shame. Im sure there could be an easy way round it other than having particles seperate from water geometry.

Id like water particles that when it meets the standard geometory, it blends into it and is clever enough to calculate ripples using real time pyshics etc...

I never really look into plugins too often but there must be a suitable water simulator out there someplace?

~So any info on the material u used on them particles plz?

Hi,

thanks - I'm pretty sure there's no 'one size fits all' water solution, that's commercially available. Flowline is maybe the closest I've seen movies of, but I've no idea how it works or what the plans for it are.

The existing ones tend to be geared towards larger scale, like Dreamscape with no separation of fluids, or smaller scale like Glu3D/Realflow which are not really practical for large masses of water. You just have to comp what you need really.

Regarding the material, it's nothing special, just got a bit of a translucency material and a high specular. It's more the object motion blur and 1 frame spin rate on the cubes that is giving the fluffy look.

Cheers

Steve

Steve just wondering, you use obejct motion blur, have you tried with image mb ? just to test it ?

anyway i would like to see the difference.


looking great.

Hi,

actually I use a little IMB as a render effect on top.

The problem with image motion blur, is that it's not great on extreme rotations (the cubes are spinning 360 degrees a frame), and also it smudges highlights, which is quite a drawback.

However there is a render effect motion blur which John Burnett wrote (you can download it at www.maxplugins.de), which allows IMB to be added on top of Object motion blur, and I just used a tiny amount to blur the grain slightly.

Cheers

Steve

ok, was just wondering cause the render time of Obejct motion blur.

thx i'll look into that render effect.

/cheers

H.Eisner