This behavior was introduced in 19w14b.
The bug
Smooth lighting appears incorrect at the edges of spaces that are one block tall or wide.
Steps to reproduce
Ensure that you have the "Smooth Lighting" video setting enabled.
Create a one-block-tall space of blocks with some light inside.
fill ~1 ~ ~1 ~15 ~2 ~15 minecraft:white_concrete hollowsetblock ~8 ~1 ~8 minecraft:lightSwitch to Spectator mode and look at the lighting at the east or west side of the space.
Observed behavior
The lighting will appear overly dark and transition harshly.
Expected behavior
It would appear correctly and smoothly.
Linked issues
is duplicated by 4
MC-267936
After placing a torch in a small tunnel, the lighting is rendered incorrectly.
Resolved
MC-299504
smooth lighting is not smooth in 1×2 space and shadows are very strange
Resolved
MC-300240
When smooth lighting is enabled, in a closed space with a width of 1 and a height of 2 facing north or south as shown in the figure, the shadow display is incorrect
Resolved
MC-307767
Lighting rendering anomaly
Resolved
relates to 1
Attachments
Comments 6
The issue here isn't the 15-14 transition, as this occurs at the end of the tunnel regardless of the light level.
A screenshot is not a valid replacement for the rest of the report.
Provide steps to reproduce, expected behavior and actual behavior, or this will be closed as incomplete.