Frosted jar with liquid/ice


#1

Hi, I was wondrering what would be an efficent way to model/texture/render jars like this ones. I’m mostly interesed in the blue one.
I mean, this would be a translucent object with high roughness, but the translucent property would have a map in dirty parts. Then the interior would be like a liquid with… SSS or transmission? That “liquid” would be fractured and each piece should have a different IOR? Different roughness? Different transmission color? Should I gradient map certain properties?
I’m using Arnold but I know Cycles as well, althought iif you use other engines it will be almost the same.

I did this quick render to see how transmissive and SSS materials look like within each other, I don’t know about simulations, but if you tell me that’s easier for modeling the inside material, I’ll look into it.


#2

I’ll reply to myself, the exact result I wanna archieve is explained in this video (https://www.youtube.com/watch?v=VirC8QOVp3o)

//youtu.be/https://www.youtube.com/watch?v=VirC8QOVp3o


#3

Hello Daniel and wellcome to the forum. Actually that substance is problably Cu sulphate and its crystals, when powdered are quite similar to small rocks https://goo.gl/images/6hoR31 . You can indeed use a noise in order to obtain that effect and probably that would be the easier way to do it. I suggest before creating a glass inside a glass that you try a few more tricks. The first that come up to mind is to create model the outer bottle, add noise and a map for roughness and then do not detail too much the inside. Just create the content mockup + a diffuse map that use a noise. It should be ok.
If you want to go a more realistic way I suggest to watch the entagma tutorial that you can find in sidefx.com site about modelling a crystal. In that way you can model a better interior using small rock noises and creating a boolean. Again I won’t use a glass material since it will increase a lot render times.
If you would go for the total realistic way you should create the bottle, add a simulation (grains in houdini as an example). Attach clones of small crystals and use SSS for each one of them. If this last idea seems crazy it is, but it was indeed used (also simulating wet rocks) , just have a look here https://www.fxguide.com/featured/the-tech-of-pixar-part-1-piper-daring-to-be-different/ .
Ok if you are still reading probably you are thinking I’m a bit crazy and that you don’t have a renderfarm for that… but… the great Raphael Rau gave a try to this technique using OTOY. You can see the results and a small explanation about creating 5 millions grain sand in a (beefy) PC here https://www.artstation.com/artwork/nBNVo.
Giorgio


#4

Thank you for all those ideas, even those that are not viable. English is not my mother tonge and there are some things that I don’t know what are you referring to exactly. But here’s what I did (It still needs some tweaking but it’s going in the right direction). You said to model the outer bottle, which I suposse is the bottle as it is in real life, althought it sounded like modeling it like it was fully solid. Also you told me to not model a glass inside a glass but do not detail too much the inside, so idk what do you mean by that either… Modeling solid opaque rocks? Also I don’t know Houdini, I started this year learning 3DS Max at college and I knew some blender before it.

Anyway, here’s what I did, I painted a gradient in photoshop and plugged it into diffuse and transmission. Transmission weight is set to 0,97, so it looks like it has some SSS, I will try painting a grounge gradient for it like I did with the color transmission and difuse and I will have to with the roughness reflections as well since now it looks too uniform but you can see the setting I used in the picture if someone is interested.

Another video that has helped me as well was THIS one on how to make ice which is what those bottles look like, although arnold doesn’t have an equivalent translucent shader afaik which acts as a quick SSS and that video was made before principled shader was first added to blender cycles so it can’t be followed 1:1.


#5

So I will try to explain myself a bit better. About modelling. You should model the bottles with a “correct” or plausible thickness. The content of your bottle should be modelled too. You can choose to go for the bottle filled with the small “rocks” or to model the whole inside as a “massive” unique block.
So about the glass inside the glass.
If you model the bottle as it is in reality you should have:
A) The outside environment,
B) The bottle (with its thickness)
C) The transparent/reflective/refractive content.
So you will have the rays go throught the glass of the bottle and then the transparent content. This will require the render to make a lot of “bounces” for calculating a “correct” results and you will probably obtain a “dark” result.
But if you think for a moment how in reality transparent stuff (glass, plastics, sand) looks like when it is crunched in smaller parts (think about sand)… the final aspect will not be transparent. It will be similar to a diffuse object with reflections. So you can cheat this aspect creating a unique “content” object with a diffusion and a (low) reflection channel.


#6

Mmmm i think you’re going to have to sprinkle particle effects on those things to get all that dust and crud on there.

nothing wrong with that though.