just a quickie…
does GI usually work through glass onto a displaced material?
i probably just forgot to check/uncheck something…
vrayshadows will go through glass, assuming the glass has the ‘affect shadows’ set in the material.. Skylight doesn’t go through by default, but the light cast by a vraylight skylight portal will go through.
thanks for the reply, but that didn’t really answer my question.
i’ll try and explain a bit better…
i have a displaced surface inside a glass box.
the displaced surface receives light from direct lights.
Everything outside the box is lit by GI, but the displaced surface inside the box doesn’t seem to be receiving any light.
other items inside the box which aren’t displaced seem to be receiving light from GI.
i’ve checked the ‘affect shadows’ box for the glass material, and direct lights pass through it so i know it is transparent.
hope that makes things a bit more clear. 
indirect illumination will always pass through transparent vray materials, as long as you keep “refractive gi caustics” checked (default). it is diminished/coulored based on your fog/refraction coulors. light is also prevented from passing through íf you use higher reflection values (as it the reflected amount does not get through). ticking affect shadows does not alter the result for bounced light or skylight
best regards, michael
edit: just recreated a part of your scene by putting a displaced sphere inside 1) a glass block and 2) a glass box (solidified), and in both cases it recieves skylight, but probably your problem is an issue with the old style displacement as i can’t test with the v1.09 here
thanks… i’ll have a look at my settings. i think it might be the ‘refractive GI caustics’
unfortunately, 3ds seems to have locked up…
thanks for your help, i’ll let you know how i get on.
duh! that was it.
i knew it would be something simple!
/punches self in face for being so bloody stupid…
What do you mean with ‘by default’ is there any way to get skylight thru glas else?
regards,
robert
good question.
exuse me but isn´t the skylight going throu glass when a skylight portal is used?
when this option is on, the Color and Multiplier parameters are ignored, instead the light will take its intensity from the environment behind it.
or is “the environment behind it” not what i set in the GI Environment options?
Imagine that the Vray light is a big lense once you turn on the portal option. It will sample everything behind it and project (maybe amplify even) it through to the other side. Just a “focusing mechanism”.
As for GI / skylight through glass, just turn on the refractive GI caustics check box at the top of the GI rollout