God rays in render

Can we do! ‘god rays’ rendering in rhino or do we need 3rd party renderer.

i use mac osx so v-ray not an option

what options do i have?

attached image is from a v-ray render from internet

many thanks to everyone who replies to my queries.

Hi -

-wim

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Crepuscular rays will require a volumetric environment as Wim alluded to. I’d suggest looking at apps that could do this on Mac and export your model to render it there.

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Until we support volumetric shaders you can pretty easily simulate them with actual geometry though. Here a very quick setup:

volumetric_cheat.3dm (581.6 KB)

With some extra work on the material you can bring some extra depth to the effect, like maybe with a gradient on the alpha channel.

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Neat trick! I’ll steal that :slight_smile:

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OMG

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try Twinmotion :+1:

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Here a quick one with a simple Gradient texture where Color2 is set to a Dots texture.

Dots Color1 is white, Color2 is dark grey 15,15,15. Gradient texture Color1 is dark grey 20,20,20.

Also changed tonemapping to filmic medium contrast. Multiplier and Bloom post effects are also used.

Anyway, with more time you could get better results. And using _Render you’d get less banding than in the viewport, obviously.

@gustojunk, image below named specially for you :wink:

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Procrastinating, so threw in that pale blue dot as well…

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Thank you all for your replies.

Also the example simulated solution is great, but my actual model is a bit more complex than the one I showed in the original post… see below.

That is indeed a ‘bit’ more complex. Maybe use Grasshopper to create the volume meshes from where-ever you have your light source?

I’m sure the #grasshopper users here can help out with that.

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maybe a stupid suggestion, but if you have a good work horse that should work. i tried that myself on an 8 years computer because i wanted to do real volumetric light and no fakes as the software does, or at least i wanted to see if i can get that working.

i created a ton of tiny particles which reflect in the light, a light with a (probably) hard shadow throwing over your geometry will then create the volumetric separation.

but for god sake just try the free blender render or use a different app till this is up and running.
actually i tried to create volumetric smoke but thats not far from what you need. here the result

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Nathan, In Opacity, What is the difference between Alpha and Amount?

Opacity amount is how much opacity there is with the material. Here the base color of a PBR will function like a light filter. The color (and the darkness of the color) what light goes through and how much. Full black on a PBR with opacity set to 0 will still be full black.

Alpha is how much of the material is visible. 1.0 is fully visible, 0.0 is fully invisible

The glass pane in the corner has color 0.8, 0.1, 0.1 with opacity amount 0.0 (fully transparent for the color) and alpha 1.0 (fully visible).

Going to the right alpha decreases in 0.2 decrements, I selected the last object to show that alpha 0.0 means fully invisible. If you look closely you’ll see that the IOR effect of glass becomes less and less pronounced with each decreasing alpha step.

Going from the corner to the left alpha stays 1.0 and opacity amount stays 0.0. Instead I tweak the lightness of the color value. Essentially going from a full dark red to light red. Lighter colors will give the impression of lightly colored glass (or whatever material IOR you used).

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So “Amount” is the alpha value amount of secular light or reflectivity?


Grayscale vs Opacity Amount

Amount is how much opacity there is. 1.0 means fully opaque, 0.0 means fully transparent (with taking light filtering into account - darker colors with opacity amount set to 0.0 still can mean the material can ‘block’ light).

Ok, I get it. It is not intuitive as expected.

Helps for making smoke:


(from: Smoke Schools: Opacity Training and EPA Method 9 Certification)

Here is Alpha


Grayscale vs Opacity Alpha

And combination using both opacity amount and alpha


Grayscale vs Opacity Amount and Alpha

So to get fog using an array of planes, you need white color + low opacity amount and alpha.

Any light color plus the rest you mentioned.

And darker colors for thicker fog, and/or increased opacity.

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