lights color through objects

Here is the situation: I am making some tests to see how different lights behave while passing through objects, but so far I didn't find the solution I was looking for. My final goal is to obtain a lampshade-like effect, where the light color is changed while passing through a semi-transparent mesh, but so far, I managed to have only a small portion of the light influenced by the object.

I tried to set up a simpler environment, with a light pointing straight to a plane with a wall behind, but still, I had no success in influencing the light that gets through the mesh. (see the attached file).

Of course I could use a script to change the light color to match the mesh, but that's not what I am trying to do. Can anyone tell me what am I doing wrong, or at least point me to the right direction?

 

Thank you so much for replying, I've never modified shaders before and I guess it will take me some time to make it good, but I'll post something as soon as I'm done!

 

Wow thank you so much! I really appreciate man!

 

Argh, I'm sorry to come back on this, but I've tried to use the shader you've posted, and I couldn't manage to make it work no matter what I tried. I've just used a simple setup with a spotlight, I've tried both baked and realtime lighting and nothing changed. What could I possibly be doing wrong?

 

Did you ever get this to work? The shader code above doesn't do anything with the Transparency material. It would be fantastic to get some transmissive materials/shadows colored by transparent texture!

 

Baking! That's the magic ingredient. I'll have to give this a shot. It may not be ideal for my current use-case, but it's good to know it's there in the future, so I can plan for and around this. I do a lot of projects with stained glass, so this is really important to me.

Thanks!

 

Yes. Many. I'm an archaeologist doing archviz of cathedrals as they looked several centuries ago. I'm literally a day away from finishing my first big project with Unity (with SEGI) as my primary renderer (and I absolutely love it - I never want to go back to traditional renderers). But these cathedrals are massive pains to UV map (I mostly do texture projection in C4D, my main modeller) and they're also heavy-poly (7-10 million polys) - so baking is kind of a no-go (hence using SEGI). Also, my clients love dynamic lighting.

I would be overjoyed with a non-baked transmission lighting model - or even colored light cookies!

So, cathedrals and stained glass. Lots and lots. Attached is a little screenshot of the sort of thing I'm talking about.

Thanks for asking!

 

First, the cathedrals look excellent and I recall seeing these on the SEGI forum. Did you end up using the shader posted above to achieve a "transmissive" surface?

 

This shader is really saving me right now, so thank you very much. Right now the shader takes a tex2D to define the transmission color. Is it possible to multiply the transmission 2D by a color value via a color picker?

Artistically, it is difficult to author dozens of color swatches when you could use a color picker to define TransparencyLM instead.

 

Cheers! The cathedrals are fun to do, but a little time-consuming!

I did not, in the end. I just left the transmissive stuff out of the project. No one seemed to notice. I can't remember why that shader from @thefranke didn't do the trick for me, but it may have been due to the baking requirement, as my cathedrals are just too huge (in file size and geometric complexity) to realistically bake.

@doppioslash and I explored some other possibilities, but I've gotten overwhelmed with work (sorry @doppioslash) to take this further.

If anything that works does appear, I'll post back here.

 

Hi.
Has anyone test this recently? because I followed every step but nothing happens!

 

I'm trying to work out how to replicate this effect in the LWRP, but can't find any working examples. The example shader works perfectly, but I'm not sure how the magic "_TransparencyLM" line works, and as such how I'd replicate it in LWRP either in code or through ShaderGraph.

Any guidance would be appreciated!

 

Hi Rasmusn, thanks for your reply.

It's writing custom shaders that affect baked lighting that I'm struggling with. I'm not sure if it's more relevant here or under URP, but this thread was the closest I'd found thus far to what I was trying to achieve.

It seems easy enough with the HDRP, but I'm currently targeting Oculus Quest, so I need to keep things lightweight.

I stumbled over the Baked GI node in Shader Graph, but couldn't find any guidance on what it does or what I could use it for, so I don't know if it's of any use to me.

 

https://twitter.com/pigselated/status/834328861840117761
Is this what u looking for? But I tried quick scene with trasparent materials and lights. I could not achieve this effect with progressive lighting...

 

thefranke , thank you so much!
This is exactly what I've been looking for a long time!
I need exactly to bake those colored gaps!
I hope this works in Unity2018?