Light portal situation...

[Njen]

I'm modelling an interior scene and the ceiling has a few grate objects that can see out to the sky. I have attached an image that shows the top of one of these grates (though we see them from underneath). I have an existing single quad light portal inside the red lines, but the portal object shares a coplanar space with some of the geometry of the grate(example areas marked in green).

The question I have: is it more efficient to put lots of tiny quad portals inside each grate hole, or keep the existing single quad even with the coplanar faces it shares?

I hope what I wrote makes sense.

[Njen]

Is there any answer to this?

[maru]

Sorry, I somehow missed your post.

The portal geometry should never intersect with other objects. My advise would be to move it up a little bit. It's a bit like example 5 or 6 here:
https://coronarenderer.freshdesk.com/support/solutions/articles/5000501660

I would not recommend placing tiny square portals in this case since then there would be some geometry behind them.

[romullus]

In your scenario i definitely would want to check if adding portals helps at all. It may be quite opposite with such windows geometry.