V-Ray material - reflection GTR Energy Compensation error

[akos_kiss]

Hi All!
I've noticed some strange behaviour with the vray classic material and node material regarding the GTR energy conservation mode check box.
I've received recently a c4d file from a supplier that had this option visible in the node material setup. We have the same c4d and vray versions ( vray 6 hotfix 2 and c4d 2023.1.3).

When i checked on my end the GTR option was not available in the standard material (but the documentation says it should be visible). I also wasn't available on the node material setup by default but i could add it as an input node. When when i wired up a value node as boole the GTR option became visible in the node material attributes, but after a while it disappeared.

In the supplied file the gtr option was visible on both the standard material and the node materials of the scene and they were unchecked ( the reflection mode was ggx). But when i asked them about the GTR checkmark visibility they told me that it wasn't visible to them when they created a new material. So basically they had the same experience that i had.

Is this intended behaviour? I saw that the GTR Energy conservation mode is show in the documentation.
I've attached a few images to make it easier to understand.

classic_material_reflection_options_missing.jpg - this shows that the newly created material is missing the GTR option
node_editor_input_option.jpg - this shows that the option is available in the node material but not by default
node_material_reflection_options_missing.jpg - this shows that by default the node material is missing the gtr checkbox
node_material_reflection_options_available_recieve d_file.jpg - this shows the file we received from our supplier ( and they told us that the gtr checkbox was not visible to them either)

[aleksandar.kasabov]

Hello akos_kiss,

Can you please clarify if the received Cinema4D file was created with V-Ray 5? Please note that there are some expected differences when opening V-Ray 5 scenes in V-Ray 6. This parameter is generally hidden but it is kept on older V-Ray 5 scenes for compatibility. This is the reason it is not visible on newly created materials. You can check this forum post where Deyan explains this in more detail.

[akos_kiss]

Hello aleksandar.kasabov!

Thank you for the explanation and the link to the forum thread. Somehow we missed it.

It turns out that some parts of the file we received where copied from an earlier vray 5 scene that was probably created in r23. Those where the factors why we had issues.