VRayDisplacementMod, displacing in positive and negative direction

[julianb]

Hello,

3DS Max user here. I was just reading the official V-Ray help file, explaining the purpose of the Texmap mix and Texmap max values in the VRayDisplacementMod modifier.

I want to displace an object in both positive and negative direction just like in the attached example.

As far as I can understand I need to set the Texmap mix/max values to "-1" and "1" but what texture was used to achieve that result?
I always use black and white textures where blacks don't get displaced and whites do.
What colours must some of the shapes on the attachment be to get displaced in positive and some- in negative direction?

I tried creating an image with a transparent background and some white and black shapes but did not get the desired result.

Thanks for any help.

[Alex_M]

Hm... I can't see a difference when changing the min. value either. :/ For me only the max value works. I tried regular bitmap textures and procedural maps such as noise & checkers.

[julianb]

Thanks for the reply, Alex.
To be honest I am not even sure if I am reading the whole thing correctly- maybe they just displaced once in a positive direction and then in a separate render they displaced in a negative direction shifting the bitmap so that it shows in the other corner...

Anyway- thank you for testing.

[joconnell]

Min and max just sets a range that the modifier will use from your image - if you don't have negative values in your displacement map then there's mothing for your modifier to work with. If your displacement map runs from black to white, you can get negative values using the displacement amount and the shift value - if middle grey is the value in your displacement map where no displacement should occur with white values pushing out and black values pushing in you can use the shift value set to negative 50% of what your displace amount is - if you've got a displace amount of 1.0, then setting a shift value of -0.5 lets you get both.

[julianb]

Sweet, it worked like a charm Got the displacement in both directions.
Thank you very much for the help, jaconnell.

[joconnell]

high fives!

[julianb]

High fives accepted and returned