Light P2Ps don't transfer the right light level after rejoining the world (or possibly even by default) about applied-energistics-2 HOT 2 OPEN

I've played around with P2P Light a bit (in 1.20.1 and 1.21 both the same behavior), here is what I've found:

1. Create a P2P Light setup (Glowstone directly in front of P2P Light input, link with output), leave the world ("save and quit to title"), rejoin the world -> find the P2P Light output is completely dark
2. Place a cobble (or any other solid block) directly in front of the P2P Light output and remove it again -> find the output has light level 14
3. Bonus Bug: Remove the input -> note that the output is correctly marked as "unlinked" but still emits the light as before. Does not get fixed by placing a solid block in front of it and removing it again.

My best guess is that some triggers for updates are missing.

from applied-energistics-2.

I played around some more (1.21 only) with some debug printing and found some interesting and unintuitive behavior. When loading the level at some point very early blockLight is called in LightP2PTunnelPart with a correct value of emit = 15. There this.opacity was correctly set to -1 and thus calculated anew. The returned value of level.getMaxLocalRawBrightness(pos.relative(getSide())) is however not correct as it seems. It also is not consistent across multiple attempts to join the world. I've seen values of 14 (which effectively reduces the emitted light level to 1), 4 (which effectively reduces the light level to 11), 10, 9.

When I place a cobblestone in front of the output, this.opacity is correctly recalculated and light levels are correct. So my guess is that unless I force the update to succeed by placing a block in front of the output the opacity is some sort of garbage value.

As for the bonus bug: Enhancing getLightLevel() with another condition in the if statement (&& this.getInput() != null) solves this problem.

from applied-energistics-2.