expose transparency value

Hello there !

I’m using Physical material for some objects (lightbulb), and i’d like to be able to change transparency, as for some coloured lights, the bulbs are no more transparent, but opaque glass.

I can’t figure-out how to expose the transparency param to verge3D :
tried all this in 3DSmax:
– controller in the transparency slot;
– RGBA controler in the transparency color slot;
– colormap in the transparency color slot;
– bitmap in the transparency color slot;
– set an animation key;

…and this in verge3D puzzles :
– change bitmap or set value or set color… Transparency is not in the list…
– use flexible input mode to force “transparency” value

No way.

I could also use 2 different shaders, but as the material is in a multi/sub one (because i need the lightbulb to be attached to the other parts, it is one only mesh with matIDs and multiSub…

So if someone has an idea, that would help.
Regards