Question Screen Space Reflection for transparent materials

Hi! I tried to understand how this features works but cannot find any documentation about it.

I setup a simple scene in Unity 2020.b2 and HDRP v10-preview.27


You can see SSR on flat reflected opaque surface but no ssr on transparent material.

As I understand to enable it you need to do it on HDRP Asset and on specific material. After that I see something on transparent object but it looks like reflection from opaque object going through transparent.



Am I doing something wrong or it does not work?

 

+1

HDRP settings:


"Transparent Screen Space Reflection" is ON, but transparent Lit material reflections not working, if changed to opaque yes.
Unity 2020.0b6.3259, HDRP 10.0.0-preview.27

 

You can see strange effect of SSR Transparent if you place some opaque object right behind transparent object

 

No, opaque object behind transparent object- reflections O.K., but glossy transparent object (right) N.O.K.
I forget to write one thing: I am using raytraced (dxr/rtx) SSR- without raytracing SSR not working at all...

 

This is from Unity manual, what is new in hdrp 10:
"Screen-space reflection on transparent Materials
HDRP's screen-space reflection (SSR) solution now support transparent materials. This is useful for transparent surfaces such as windows or water."

My English is bad - did I understand that transparent objects (such as windows) will reflect the surroundings (such as (opaque) mirrors)?

Or is it that opaque objects behind transparent objects will now reflecting correctly? And if I want to mirror the surroundings in transparent object, do I still have to use a reflection probe?

 

Transparency reflections (both screen space and ray-traced) are working in latest 10.1 HDRP package (from GitHub with manual installation. Better start project from scratch too or it can be messy - random features will not work properly; but anyway project won't work after successful build (black screen))...

 

Are that screenshots with raytracing enabled?

 

Yep.

 

I hoped that Unity fixed general SSR because right now it's pretty bad without raytracing.

 

Nope, it's still glitchy and can't work with smoothness below 0.9 but at least they're working on transparent objects (and reflecting ray-traced GI and other effects, when ray-traced reflections are not doing that).

 

What do you mean by "can't work with smoothness below 0.9"? They have "minimum smoothness" in SSR settings which change what pixels will receive SSR by their smoothness.

 

SSR not blurring reflections *yet* - so, no matter how smooth or rough material surface is SSR reflections on it's surface will be always sharp like it's polished ...

 

Oh, yes! Now I understand what you mean by that. Here is the link to forum with WIP of ssr improvement.
https://forum.unity.com/threads/screen-space-reflections-close-to-unusable-in-hdrp.915140/

 

2020.2.0b8 + HDRP Version 10.1.0 - October 20, 2020 installed, no rayraced reflections in transparent material. If I turn material from transparency to opaque then yes (HDRP/Lit, material Receive SSR Transparency is ON).

Edit: Transparent reflection starts working with Path Tracing, but this is unusable for realtime (on my hardware).

 

HDRP settings come up really often on Unity Discord as well. There doesn't go a single week by without someone struggling with the initial setup to enable feat x.

I'd suggest Unity to put some warning in the components themselves if the feature hasn't been enabled on either hdrp asset or in current frame settings, just to make sure users understand immediately which part is missing. There's similar check on HDRP Wizards DXR section right now but users would expect to see a note on the the volume itself - telling what is missing.

 

I think I know about all the conditions mentioned, but it still doesn't work.

New Project created (2020.2.0b8 + HDRP 10.1.0):




Pipeline Wizard- Reflections and Transparent Reflections ON:


All files with HDRP settings- SSR ON, Transparent SSR ON:


Opaque aterial created, Receive SSR ON:


Material duplicated, set to Transparent, Receive SSR Transparency is ON:


Final result- opaque material reflections O.K., transparent material N.O.K.

So, please, see where I'm making a mistake?

 

Result:


Both materials opaque:

 

Finally!!!



Thank you, I understand that making the settings so that they are as flexible as possible and meet all possible requirements is difficult, so the result is a very complicated setting, but sometimes I go crazy about it.
Thanks again.

 

Info: If you are migrating from HDRP 10.0 to 10.1 and have problems with existing transparent materials (or the build crashes) then try HD Render Pipeline Wizard-> Upgrade HDRP Materials to Latest Version. It helped me.

 

this is still not working for me. I've done everything in the suggestions on this forum

 

only on certain materials tho, quite perplexing.

 

´
for HDRP 12 no "HDRP Default Settings". This time "HDRP Global Settings":


this is not in "Realtime Reflection" section!?!! but "Lighting"
works fine

 

Its a bit of a mess to have have so many steps to enable an important feature. a big red 'enable reflections' eveywhere
button would be nice

 

Hi, i was messing around with hdrp graphic settings (i have hdrp 12.1.0) and to solve this issue i found this forum, but there is a problem i can't solve. I followed all the instructions above and now transparent objects can reflect other objects but transparent objects don't appear in reflections with theese tecniques: ray marching, raytracing and mixed (i am using mixed in this case) as you can see below. Of course path tracing can cast transparent objects but it's too ugly.
That's also quite strange because i searched all the options related to the transparent objects both in project settings and material settings.

 

So I can fix this just by changing the rendering order, can I?

 

Oh my goodness. I just spent a few hours wondering why I couldn't get Transparent SSR working, and finally I found it with your help @chap-unity :



So to summarize, for Transparent screen space reflections to work, it has to be enabled it in the following places:

• Need Project Settings / HDRP Default Settings / Lighting / Screen Space Reflection enabled and the Transparents sub box enabled (shown in above image)
• ALSO need your Project Settings / Quality / HDRP / Lighting / Reflections / Screen Space Reflection and the Transparent sub box there enabled
• Need to have a SSR override on a volume in your scene (such as a global volume)
• Material (custom or otherwise) should have the Receive SSR Transparent box enabled, assuming it is a Transparent surface type

 

I spent hours trying to figure out how to get the Screen Space reflection and Transparents boxes from being grayed out. This helped me a lot. I didn't see the settings in the Project Settings / Quality / HDRP / Lighting / Reflections / Screen Space Reflection area until I saw this, thank you!

 

So transparent objects don´t appear in raytraced reflections - is this still the case in current hdrp version?
If yes, are there any plans to fix this?

 

Thanks for your honest reply