Area light is in portal mode invissible allways(b8)

[Micha_cg]

... or is it not a bug. Than should the invisible option greyed out better.

[flipside]

Area light is in portal mode invissible allways(b

Yeah this is supposed to be this way.

Light portal is used if you render interior scenes and you put a rect light in the window. The portal will guide the light for the skylight into the room. So to use portal you need skylight or some other GI light to guide trough the portal!!

[Micha_cg]

Area light is in portal mode invissible allways(b

Interesting. If I understand it right, it convert the GI light in a standard light. So, it works only in GI mode as portal for better light calculation?

[flipside]

Area light is in portal mode invissible allways(b

Just try it:
make a closed room with only one window.
Light it with a skylight (for example multiplier 3 to get enough light in)
Notice that it is difficult to get light inside the room.

Then make a rect light, pointing in the room and position in the window opening. Use the portal option.

Now you should see more light entering the room. It simply picks up the skylight and throws it inside of the room.

Indeed you need GI for it to work. This portal is specially made for window purposes, area lights in general are not.

[Micha_cg]

Area light is in portal mode invissible allways(b

Thank you for the hints. I will test it.

[Micha_cg]

Area light is in portal mode invissible allways(b

Hmm, my tests here show me only a white arealight. I get no portal effects. I have tested a colored environment and a HDRI. Also, the arealight intensity button works (should it not) and the color of the arealight is viewable in the scene. My GI is IR+LC. At the arealight only "portal" is enable.

Could you test it too please? Should it work for a HDRI light too?

[flipside]

Area light is in portal mode invissible allways(b

Ok you're right, I think portal isn't implemented yet.

When using portal mode, these parameters should be disabled:
-light color (it should pick up the environment light, so it doesn't have its own color)
-multiplier (same as above)
-invisible (a portal is always invisible)
-ignore light normals
-no decay

So the ones used to control the portal are
-enable/disable
-of course the portal checkbox
-store with ir map
-subdivisions

Here's an example from max. You can see that the portal picks up the environment hdri light, and throws it inside the room. Shadows are very accurate because they are direct. I chose a colored interior hdri so you can see very well that the color is transmitted trough the portal.





Here is the image without any light in the opening: