Light Portal

[Gecco]

Hi, i used fR before and there was a sky and a light portal option for area lights. I thing it's a nice feature since it collects gi rays and sends through a hole (a window for example) making a better gi solution inside the room.
I see an option "Light portal" on the vray light tag under the area light section. I assume it is something similar to fR's. But if i have a sun and a sky outside the room and put an area light in the window and set portal on, the room gets more light from the window unlike if i don't use it.

Is this the way it works and i missunderstood something about it?

[stefan]

yes light portal is in area options.

i think as it collects the outside light maybe there is more getting in. can you give us a scene please so we can look into?

i must say i never use it cause vray doesnt really need it very much. it brings light to the hardest points at good speed.
but we look into it if you please post a file to test.

thanks
stefan

[Gecco]

Oh, i found the problem!
The "no decay" checkbox is default on. If i turn it off i get the correct intensity of light.

Here are some testing:

1: no LP - original
http://www.kontir2000.hu/3d/vray-1.jpg
1:33

2: LP - store with irr.
http://www.kontir2000.hu/3d/vray-2.jpg
1:42
I see some difference, the light has a little more intensity and more bluish color on this pic. The GI quallity looks like the same.

3: not store with irr.
http://www.kontir2000.hu/3d/vray-3.jpg
1:55
Same as the previous but more accurate shadows, more time, and some grain.

So it looks like using portals is not as needed as in fR.[/img]