Raw GI render element odd behavior

[Muhammed_Hamed]

Hey,

The Raw GI render element changes completely depending on if a GI render element exists or not. This happens with all scenes
From my testing it looks like the Raw GI renders correctly when a GI element is present.



Steps to reproduce,

-Use my shaderball scene here,

-Swap render engine to CPU, and check Use Render elements/Use VFB

-Go to outputs/vray_render_channels1 , It has some render elements setup, just add Raw GI render element

-Now start the IPR/Production rendering, The Raw GI element would look like this



-Now stop the IPR and delete the GI render element, then start the IPR. This is how the Raw GI looks like now



Best,
Muhammed

[Muhammed_Hamed]

Something else about the premade templates, "back to beauty advanced"
It uses RawDiffuse, RawReflection Filter, and RawRefraction Filter
Isn't the correct setup Diffuse, Reflection Filter and Refraction Filter?
Because RawReflection Filter for example, doesn't use any fresnel??
Or is there a different workflow to comp Beauty using RawReflection Filter somehow? Can someone explain?

[chakarov]

You can check how to use "Back to Beauty" and "Back to Beauty Advanced" here:
https://docs.chaosgroup.com/display/..._Color-b2bComp

[Muhammed_Hamed]

chakarov Well yeah, in the link Diffuse Filter, Reflection Filter, and Refraction Filter are used
Not Raw Diffuse, RawReflection Filter, RawRefraction Filter...(which the template uses)

You cannot get Reflection from multiplying RawReflection Filter and RawReflection (again, RAWReflection Filter doesn't use any fresnel)
It has to be Reflection Fitler X RawReflection

[chakarov]

Looks like the template has some wrong elements, I`ll fix them for next nightly.

[Muhammed_Hamed]

Thank you!
On using the 3 correct elements I mentioned, the comp works nicely
Unless you hit the first issue I explained in my original post. Let me know if you can reporoduce that

Here is the setup in Nuke(After avoiding the RawGI issue)

[chakarov]

What is your OS, Houdini and V-Ray build ?

[Muhammed_Hamed]

Windows 10
Houdini 17.5.460
the nightly from yesterday
vray_adv_43002_houdini17.5.460_fe3ffda_6790_instal l_windows

[Muhammed_Hamed]

RawReflections, has the same behavoir

The only difference between the 2 renders is that I added a GI and Reflection passes, this magically makes RawGI and RawReflections render correctly

[chakarov]

Well seems this is not a bug.
https://docs.chaosgroup.com/display/...ender+Elements

In help page is written that rawGI works with enabled GI element. I guess this is valid for rawReflection also.

[Muhammed_Hamed]

Ahhhhh
Thank you!

I came by this page multiple times today and never paid attention to the note :I sorry
Maybe if the note was in Red bold text, I could have seen that. or I just need more sleep
It definitely didn't work like that in the past. Last year I was using Next for Maya without bothering with the reflection or GI passes. Good to know how this works now