I’m currently struggling to achieve a certain look of a bubble bath.
If you look at this reference image, I don’t really have a starting point on how to achieve that modeling and shading of the bubbles, or rather what features of VRay I can use here or what way I would go to get that result.
Do I model the main geometry by hand, displace it (with what map?), or use MultiScatter to distribute little bubbles? PFlow for the bubbles? How do I get this whitish SSS look with very refractive and sharply reflective materials? Does anyone have some starting points for me? Or does anyone know a good tutorial for this kind of work? I also would have Houdini available if that helps. I try to keep it simple since it is an important but relatively small element in the scene.
Okay, I see. I feared something like that. It’s not possible for us at the moment to buy a new plugin for this :-/. I’m currently experimenting with a base geometry and scattered bubbles on top of it, all with SSS but its killing my rendertimes…
i know we all want vray to do everything, but it would be good if vray had all of the shading/rendering techniques that phoenix uses.
to be honest im not sure wether it does or not, but i doubt that phoenix is doing sss on its bubbles, but it still looks good! that shader should be in vray too, imho
we now have the volume grid thing, which is a good start
Yeah…would be nice, but I’m not really bothered by it since the chaosgroup guys are the only software developer I know that produce service pack changelogs where I “WOW!” after every line. ^^
Okay, that may be an option then.
Anyways - how does the foam in PhoenixFD get so nice white? It has to be SSS, doesn’t it? Otherwise the light would be totally absorbed and it would get darker.
For everyone interested: I am on the right track with a base geometry of the rough form of the bubble distribution which I assigned a VRayScatterVolumeMtl and tweaked the settings so the overall reaction to light mimics the foam. Then I distribute the bubbles over that surface with MultiScatter, the bubbles having a BlendMtl of another ScatterVolumeMtl with a Glass material. The bubble geometry is a shelled sphere.
So far it seems to work although it takes a while to render…
Well…this is the result of an 800px rendering after 12,5 hours on two machines with 3.4Ghz.
I am severely disappointed in the rendertimes.
I will now try to get the time down by limiting refraction depth even more with a ligh grey exit color.
Anything else I might wanna do?
EDIT:
For comparison - this is without the bubbles, it took 5 minutes to render.
Now I wil propably make a second rendering with a glass-like surface ontop and a heavy bump so I can get the sparkling effect - except anyone else knows a solution to get that nice sparkling
well that does look very nice.. even without the bubbles. why not render the bubbles seperately with a simple glass material, ior=1 and comp them over your base foam..
Thanks - yeah I am actually considering rendering seperate and comping. First I wanna try by layering a normal surface on top of the foam with a heavy cellular bump map and glass material and see what happens
Thin Film is also a good idea! Will post updates.
Here with a glass “plate” on top and the ThinFilm reflection.
I’m not quite satisfied with it, since it gives a too harsh edge. Maybe really comp but I would love to get the effect in-camera.
Interesting thing: If I reduce the visibility (under object properties) of the glass-plate on top to 0.3 the rendertime severely shoots up (guess is around 5-10 times). This shouldn’t hapen I think.
i think it would help if the bubbles didnt entirely cover the foam underneath. just a few patches of larger bubbles. the foam looks great.. the skin of bubbles is too uniform.
