Trying to see the sunlight

[Glanbade]

I've been trying to think of a way to get sunlight into my fortress, safely. Does anyone know if a floor grate lets in sunlight? Or maybe, if it is made of clear glass..? Or maybe iron bars. I do not like the idea of a non-covered hole anywhere directly into my main structure... for now the best advice I can find is to make a meeting area in a space that is "outside".

[Other]

Due to the way the game handles light, anything that has ever been touched by the sun is "light" forever, even if you build a ceiling over it. So your glass ceiling would work, but so would one made of granite blocks. However, there is a difference between "light/outside" and "light/inside" in terms of how your dwarves react to them.

In the previous version, any dwarf who spends a long time underground (roughly two years) can become cave-adapted, and once that happens, they start to get sick when they go out in the sun. "Light/inside" tiles pause that counter, while "light/outside" tiles roll it down (at an accelerated 10:1 rate). If you plan to have your military do any fighting on the surface, training them above-ground, or giving them regular time outside, will keep them from starting combat already puking their guts out. Unfortunately for a tile to be considered "outside", it must be open to the sky, which makes it hard to protect such areas from flying threats.

I don't know if cave adaptation works the same in the Steam version - I have not seen it, but my oldest fort in this version is only about 5 years old, and I've had my dwarves running out on the surface regularly, so I might not have seen it yet even if it works exactly the same.