Alpha material "shine"

hi there, currently im reworking our 3D Trees to fit to the new LOD
requirements. In this context i want to decrease the “shine” at my alpha
textures for the branches and leaf. as you can see at the screenshot, whenever
the sun hits the faces applied with the alphha material from behind , i notice
some strange shine at those faces.

the roghness channel is pure
white, the metallness pitch black, from this side there should be no shine
applied by the PBR material. Are there some settings for the material to avoid
the shining alpha textures?

Hello @BlackJack We have a similar result with the trees provided with asobo
package but the material are set as double sided (that’s the cause of the
shine being visible from behind) and that doesn’t seem to be your case. Can
you confirm the leafs being illuminated are facing towards the camera and the
one facing the sun are not rendered since the double sided option is unchecked
in your picture? Regards, Sylvain

Hi @FlyingRaccoon thats right i didn´t use the double sided alpha option due
to the note in the documentation not to use it at the moment. faces which
point direct to the camera and being illuminated from the back seem to have
this behaviour, i think i found a pretty good example:

@BlackJack I’m struggling to understand how these faces can be lit if their
normal is facing the camera. If I take the Tree_Acacia01 object from the
default package, the leafs facing the camera only have ambient lighting.

The leaf material here is double
sided so the leafs at the back. Could you provide us with your blender source
for this tree so we can investigate where the problem occurs? You can provide
a OneDrive/GoogleDrive/WeTransfer link in a private comment using the option
below the submit button. Regards, Sylvain

Hi Sylvain, i noticed the same behaviour with the Tree_Acacia01 tree:

Hello @BlackJack The Tree_Acacia01 has the problem because it has double sided
material. We identified the problem: your leaf polygons normals are smoothed

If you have flat ones, the
problem does not occur: Regards,
Sylvain