3.30.02 beta + Max 2016 SP1: VRayEnvironmentFog quality settings not working (?)

[LudvikKoutny]

Hello,

I do no know if this is a bug or I am doing something wrong, but:

Whenever I used VRayEnvironmentFog in past, I adopted performance optimization workflow of slowly increasing step size just before I start to see banding artifacts (cuts) due to the insufficient raymarching density. Then I would settle for a value that is right below the swet spot where banding starts to show. Once done, I would measure depth of my scene from camera, divide it by my step size, and I would get a number I would use for max steps value. I remember this workflow working flawlessly, but in latest 3.30.02 beta, I just can not get it to work.

Here is a scene rendered with 400 cm step size and just 1 max steps. 400cm is about the distance from camera to the window, and 1 max step just does not make any sense, so I should get some crazy result, yet this is what I got:


Now when I set setting to something more reasonable - 5 cm step size and 1000 max steps, I am getting identical looking image with the same rendertime:


So this leaves me confused... Is this a bug? Or is there some new way VRayEnvironmentFog is handled in V-Ray 3.3?

[vlado]

The raymarching steps only matter if you have a texture on the fog (or a gizmo with fadeout); if it is just colors, the fog will use the stochastic subdivs parameter, which is now ignored by default in favor of the min. shading rate parameter. I should probably grey the parameters that are not relevant for a particular setup.

Best regards,
Vlado

[LudvikKoutny]

The raymarching steps only matter if you have a texture on the fog (or a gizmo with fadeout); if it is just colors, the fog will use the stochastic subdivs parameter, which is now ignored by default in favor of the min. shading rate parameter. I should probably grey the parameters that are not relevant for a particular setup.

Best regards,
Vlado

:O :O :O

Was it always this way? As far as I remember, last time I used VrayEnvironmentFog, which was about a year ago, with 2.4 version, I used step size and max steps to control VrayEnvironmentFog, which had no texture. My memory may be fooling me, but I pretty confident those parameters made a difference.

[vlado]

Was it always this way?

Yes.

Best regards,
Vlado

[LudvikKoutny]

Well, now i feel really silly. I guess I was using gizmo with fade... otherwise I can't explain how I saw those changes make difference.

[vlado]

Like I said, we should probably make it more explicit in the UI what is going on.

Best regards,
Vlado

[LudvikKoutny]

I agree, and looking forward to it. I think there's a quite a few more places where smart freezing of UI elements could avoid confusion