How to visualize translucent shadow

(Willem Derks) #1

I’m cross posting this from the regular rendering discourse.

@nathanletwory Can you tell if Cycles will be able to render shadows “through” translucent materials?
If so will that be soon (couple of weeks) or should I continue my search?


(Brian James) #2

I bet you or I could do this in Cycles in Blender but Nathan will have to say what the chances are on getting the light path component functionality over in Rhino Cycles.

(Nathan 'jesterKing' Letwory) #3

Begin this week I implemented exactly this in my shader conversions:

Light path node has been in use already for a long time in RhinoCycles, just not for transparent materials to support lighting through such materials.

FYI, the RhinoCycles world shader has been using light path nodes for a long time already to be able to simulate background vs reflection vs skylight envs in one.



(Nathan 'jesterKing' Letwory) #4

Note, I misunderstood the first question, thought it was about light through glass-like materials lighting other objects.

The particular case you linked to isn’t yet implemented, but if Brian says he can do it in Blender Cycles then it is a matter of writing the proper shader graph and it’d be in RhinoCycles.

edit: tried quickly in Blender Cycles. It is just a matter of mixing a translucent BSDF, which results in:

I still need to wrap that particular node, but that’s a matter of 5 minutes. Eventually I can see there’ll be a material with the translucency node, a (DEV) version I could add also in short time, but such materials (currently all Cycles custom materials in Rhino) are for development, and shouldn’t be relied since they’re for test usage mostly.

edit: wrapped and a test material added, I’ll update soon with some visuals.

(Willem Derks) #5

Hi Nathan,

That is great ! Thanks for the answers, insight and examples. If it will not be implemented in Rhino in time for my project, I will see how much I can achieve in Blender. (good reason to explore blender a little more)


(Nathan 'jesterKing' Letwory) #6

I’ve committed this morning code that adds a test material with translucency.

This video shows both the transparency with lighting of objects behind objects with transparent material, and as a bonus the (developer) translucency material - this should be in any next build (and as another reminder: this is not a final material, but might help you “experimenting” with it for now).

Note though that I accidentally broke the glass and gem meta materials, making such materials by hand still works though.


(Willem Derks) #7

Hi Nathan,

Awesome! I really appreciate your quick response and getting this implemented.
Remind me how often is the WIP updated agian? Is it something to expect implemented in the next 2 weeks?


(Brian James) #8

@nathanletwory @Willem

Here you go… (81.1 KB)

(Nathan 'jesterKing' Letwory) #9

[quote=“Willem, post:7, topic:19277, full:true”]
Awesome! I really appreciate your quick response and getting this implemented.
Remind me how often is the WIP updated agian? Is it something to expect implemented in the next 2 weeks?[/quote]

If no stop-ship bugs are reported I suppose next Tuesday :slight_smile:

Cool! Exactly what I earlier posted, and also implemented 30 minutes after that :smile:


(Brian James) #10

Nice! I’ll look for the translucent material to test it out.

(Willem Derks) #11

Hi Nathan,
Just got the latest WIP installed and tried to find this DEV translucency material. Can it be it did not make it in this build? I ask just to make sure I do not miss it somewhere:


(Nathan 'jesterKing' Letwory) #12

I committed this last week (the day I posted about it), so it should be in.

What does the command-line says the RhinoCycles version is?

(Willem Derks) #13

HI Nathan,

RhinoCycles 6.0.15112.3491

Hold on… I now see that I have the April 22 WIP and I see there is an update available.
So it must be I’m behind on updates, I’m going to wait for the auto update to kick in or manually download.

I’ll report back with my findings.


(Willem Derks) #14

Hi Nathan,

It’s working as expected now! Thanks.

Looking forward to start working with this!

To give some context: I’ve just started a new project for the designer Dennis Parren that uses this effect:

Many Thanks