Hello all. Can one of the Corona devs or pros clarify the best way to deal with ice cubes in colored liquid? Nested dilectrics dont seen to work - the ice looks like it’s intersected by the liquid. I’m using a workaround with a slicer object slightly inset from the ice cubes but thats a PITA.
ALso while I’m here a question on physical material glass. I’d like to reduce the reflection at the front WITHOUT effecting the refraction of the glass. Is using the legacy materiial the only way to deal with this?
Thanks in advance
Hello!
Regarding 1 - Ice cube “pushing” the liquid away - the only solution I could find so far was using the Slicer mtl. 
Regarding 2 - Controlling the reflectivity of a material without affecting refraction IOR - you can scroll down to Advanced options in your material and check “Enable non-physical properties”. This will give you Legacy material-style controls over reflections and refraction.
Regular render:
Non-physical - reflections removed, refraction on:
You can even use this with Corona FrontBack to get different colors of reflections on the front and back sides
Non-physical - reflections on front but not back side:
Non-physical - reflection color with FrontBack:
Ah - excellent. I didnt know this was there. Thanks!
It’s hidden for a reason. We don’t want our users to make the Physical Material non-physical. 
Ah, sorry, I didn’t notice this was C4D! Please let me know if anything looks confusing in the 3ds Max UI.
@AramAvetisyan I think the idea here is to get an effect like this, so that the ice cube “booleans” the liquid:
Rather than what you get when two volumes intersect without a slicer:
Thats correct Maru. Corona doesn’t seem to have a resolved nested dilectrics system, so getting correct/visually pleasing results is very hard to achieve.
Feature request please! (The page from Arnolds description of the desired system is here for reference: Help
I came up with another idea. Attaching the scene (this time it’s c4d ): c4d-3dvol.zip (113.3 KB)
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Use Volume mtl in “inside volume” mapping mode for the liquid
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Drive its absorption using the Distance shader (inside ice = white, outside = your desired absorption color)
Here is what it looks like when the ice cube is hidden:
The material setup is kinda complex, but the advantage is that once you set it up, you just specify for which exact objects there should be “holes” in the volume mtl’s absorption. It will also work if you fully submerge an ice cube.
Happened to see this post and though I’d chime in even though I’m a Max user. It seems like the issue of intersecting objects have been resolved, and there are multiple ways of going about this. But I’m wondering if the concept of nested dielectrics are flying over our heads. I’d suggest having a look at these excellent videos about it:
It was a while since I saw these. But as I remember… if you want to correctly render refractive objects like a liquid in a glass, the old trick of just a push modifier to make them intersect isn’t enough. So what Chris does here is that he detaches the intersection/interface and creates a new material for that that has a new IOR that he manually calculates. But as I said it was some time since I saw these. Anyway, it’s a super cumbersome way of doing it, and it doesn’t really work for animation. I thought I’d hack it with a clever setup with instanced objects and distance textures, but I ran it to the old recursive loop checker in Max and gave up and forgot about it. Could’ve probably solved it by not having things instanced.
Anyway I think he claims that all of this is possible to solve on a renderer basis. But It seems like a niche problem that only get you the last 20 percent (or less) of the way to realism. There was a post in the v-ray forum ages ago, but it didn’t seem to really catch any ones interest.