Lighting Information

I come from the modded Minecraft community which is at least 1.12 behind. But coming to the RTX beta I wasn't aware of what was vanilla Minecraft and what was modded. Then I learned that there are two different versions of vanilla??? Silly! There is a great feature in modded that allows you to tell what is lit up, to be not spawnable, and what is not with a simple button press. Especially now with the RTX enabled it's hard to tell what is actually not spawnable. If you could press a button (F7 maybe?) that brings up little yellow X's where a spawnable surface is, or a red X where something can spawn even if you are closer than 24 blocks away.