Vray6 - Forestpack V7.4.3 - Different Results

[RedStar]

So I know this is not 100% a Vray issue, but this is something that has changed when I updated to Vray6 and the latest forest pack for it to render in Vray6.
It seems my scatter objects now have different visual results, tones/shadows are much darker.
Any thoughts?

Vray5

Vray6

[RedStar]

I think I found the problem. If anybody runs into a similar issue, seems with the update of both plugins, for whatever reason Forest Pack made alpha not fuctional on the old vray material. I recreated the grass from scratch and now its matching again.
Not sure which causes the problem, but thats the solution.

[Vizioen]

What do you mean with FP made alpha not functional on the old vray material?
Which is/was correct?

[RedStar]

What do you mean with FP made alpha not functional on the old vray material?
Which is/was correct?

So in a nutshell. When I opened up the same scene file now with Vray6 my Forest Pack materials on the grass did not have a functional alpha anymore. What I mean by that is, the alpha texture was in there, it was turned on, but instead of making the black elements transparent it just filled the black areas with black diffuse. Forcing all extra parts of my grass to render black. I had to assign a fresh Vray material an then the alpha worked proper again. No clue why this happened but it happened on 3 completely different scene files with different grass elements/textures.

[trick]

...No clue why this happened but it happened on 3 completely different scene files with different grass elements/textures.

Make sure to report this to Itoo, bacause it can be very annoying to assign new VRay materials to all geometry that has alpha maps assigned!! (I am thinking of collections of Maxtree, Globe plants, etc, etc)

[Vizioen]

Did you test the geometry if it worked without being in a FP object?

This sounds like a huge bug though.

[RedStar]

Make sure to report this to Itoo, bacause it can be very annoying to assign new VRay materials to all geometry that has alpha maps assigned!! (I am thinking of collections of Maxtree, Globe plants, etc, etc)

Yeap, emailed them as well.
I will have to explore my other scene files to see if maybe it was a unlucky glitch in the 3 scene files that I was working in currently, but if this does happen on all old scene files this can become a long time consuming process to revise materials with alphas.

[trick]

...but if this does happen on all old scene files this can become a long time consuming process to revise materials with alphas.

Me starts itching Certainly a reason to wait for a solution. There also are lot of libraries out there that use Forest presets and/or alpha mapped geometry, so it is important where exactly this error is coming from. I mostly wait a few months before switching to a new version, so can't help.

[RedStar]

Me starts itching Certainly a reason to wait for a solution. There also are lot of libraries out there that use Forest presets and/or alpha mapped geometry, so it is important where exactly this error is coming from. I mostly wait a few months before switching to a new version, so can't help.

hahahaa! Same here. I have learned from the past when Vray updates they tend to create issues to features that were always working perfectly fine, so I usually also wait for at last a 2nd release to help fix problems. But with their Sky system and Vray Decal Displacement I couldn't wait. Now its just problems here an there lol.

So I looked at some of my other heavy FP scene files and they seem to be fine as well. No idea why some of my other assets got weird. I did however figure out what is causing the opacity slot not to work. Its the "Fog Color". Somehow on the files with issues, the fog color is black instead of white.

[trick]

...Somehow on the files with issues, the fog color is black instead of white.

That's something that can easily be scripted, or solved with MMZorb. But still...it's annoying.

[vladimir_krastev]

I did however figure out what is causing the opacity slot not to work. Its the "Fog Color". Somehow on the files with issues, the fog colour is black instead of white.

So the fog colour changed when you opened the scenes with newer versions?

I tested a simple scene with a leaf (opacity) and latest versions of V-Ray and Forest Pack but everything seems fine. However if I set the fog colour to black, the opacity affected areas then renders black but this is expected.

[fixeighted]

I don't know whether it's related but there was this post which flagged a bug https://forums.chaos.com/forum/v-ray...s-fully-opaque

Could it be that between versions the fog default colour was changed, thus causing an issue?

[vladimir_krastev]

I don't think it is related. The thread you are referring to is about V-Ray GPU. Actually we are all looking at V-Ray CPU here right?

[^Lele^]

Could it be that between versions the fog default colour was changed?

That was definitely not the case.
Interesting thread, please keep any finding coming.

[fixeighted]

Oh ok...just a thought