[cgbeige]

I have a non-SSS leaf mxm that has a lambertian layer and a glossy additive layer with the proper grey matte/transmittance set for all layers. The problem is that if I set the ND of the gloss layer to anything but 1, the base polygon becomes visible (not fully transparent). Am I missing something?

[m-Que]

You mean you're using clipmaps?
If so, as far as I remember in that case ND value should be 1; otherwise you'll get that strange thing.

[cgbeige]

well I see other leaf shaders from mxmgallery with custom ND on their layers but for some reason they have no problems.

[m-Que]

Also depends on how many layers you have in your material:
-If just 1: ND=1; that's when 'transmittance' is used for clipping, but ND does affects the whole geometry, so that's why it should be 1.
-If 2: first layer with leaf weightmap; ND= anything
second layer with negative leaf weightmap - that's the one that makes clipping; again ND must be 1.

[Bubbaloo]

Weight your layers with maps instead of using clip maps in the transmittance slot. It's much more flexible that way.

[cgbeige]

sorry, I thought you needed to have both the weight and the transmittance filled to get it fully transparent with multiple layers.