How can I prevent blocks with no light value being rendered to the player?

[Toasterkid]

How can I prevent blocks with no light value and/or not a part of the height map from being rendered to the camera/player? Especially when they are capable of seeing through solid blocks while underground, such as in spectator mode.

Realizing this was just a version of anti-xray stuff, I found this mod:
https://github.com/DrexHD/AntiXray/tree/1.20.4

which seems to prevent x-raying by handling chunk rendering, specifically the ClientboundLevelChunkWithLightPacket.

Would this be the correct method to handle my problem?

If so, is there a part of this mod's code that I should start with trying to implement to prevent blocks without light value being rendered?

Edited March 27 by Toasterkid
clarify final question