Vray6 - Forestpack V7.4.3 - Different Results

[trick]

RedStar

Dit you check whether the v5-file had black fog values while rendering OK? If not: how did v6-files suddenly have black fog values?

[RedStar]

RedStar

Dit you check whether the v5-file had black fog values while rendering OK? If not: how did v6-files suddenly have black fog values?

This is what I am not 100% certain about. If the black value changed on its own or if Vray5 had it as well but it was working properly. What I do know is the scene did not change 1 bit on my end from good to bad render. I updated Vray and had to start rendering final assets for a client project, then noticed my envionrment looking different than before so had to start narrowing down the source.

At this point I do not want to really downgrade once more to Vray5 to figre out more about this, at least now I see what caused Alpha to not work so I can fix it quickly. Luckily all my other big fpack scene files are rendering as they were which is wonderful.

[^Lele^]

If you could pass us a scene, we'd be grateful.

[vladimir_krastev]

Hi I tested the following - created a scene in 3ds max 2022/v-ray 5 with black fog colour and rendered, here is the result:


I then opened the same scene in 3ds max 2023/v-ray 6 and rendered and here is the result:


I don't know why it renders differently as you can see in V-Ray 6 all the opacity affected areas render as black.
I am not using forest pack - just a plane with VRayMtl assigned to it and a dome light.
This might be a bug, let me do a bit more research and I will get back to the thread to eventually share the info or report it as a bug.

[^Lele^]

The blackness disappears when thin-walled is checked.
I'd chalk this to a bug, as opacity should not have anything to do with the fog color.
Run the script below to fix the offending materials while the devs work on a proper fix.

    for m in ( getClassInstances vrayMtl) where (m.texmap_opacity != undefined and m.texmap_opacity_on) do m.refraction_fogColor = white

[trick]

I just had a quick look in a bunch of commercially available assets and it seems some have a black fog value. Since I never had any problems rendering transparent areas as black, I also think this must be a v6-related bug (or change!). Just to be clear again: I don’t have v6 (yet!).

[Vizioen]

Good to know, hopefully this will be fixed asap.

[RedStar]

Hi I tested the following - created a scene in 3ds max 2022/v-ray 5 with black fog colour and rendered, here is the result:


I then opened the same scene in 3ds max 2023/v-ray 6 and rendered and here is the result:


I don't know why it renders differently as you can see in V-Ray 6 all the opacity affected areas render as black.
I am not using forest pack - just a plane with VRayMtl assigned to it and a dome light.
This might be a bug, let me do a bit more research and I will get back to the thread to eventually share the info or report it as a bug.

You Rock! Thank you for taking the time to do this test to show our point.

[matanov]

I just had a quick look in a bunch of commercially available assets and it seems some have a black fog value.

It will be very helpful, if you remember where are those assets from.

[trick]

It will be very helpful, if you remember where are those assets from.

Sure. But I have to look in the original libraries. Most of my assets are resaved (because a lot of the originals have notetracks and/or anim layers - especially Maxtree - which can dramatically ruin saving and loading speed and scene handling, and when Forest Pro loads these as references loading time will be VERY dramatic), so I have to be sure fog is black in the original files.
I know that a lot of the Globe Plants (just opened some of lib 19 Temp. plants) have a grey (128,128,128 ) fog color, while using opacity maps.

If I find more, I will report here.

[vladimir_krastev]

I have reported the issue under VMAX-12441 in our system for developers review.