The bug
Underground caves seem to be affected by the environmental fog added in 25w19a, making them look brighter than in previous versions, which might be a visual regression. This also causes sunset to affect underground visually, in a similar manner to MC-297562.
Steps to reproduce
Create a world in 25w18a and find a big cave.
Set your render distance high enough.
Take a screenshot inside the cave.
Open the same world in 25w19a.
Take another screenshot at the same position as before.
Compare both screenshots.
Expected result
Environmental fog color inside caves would not stay bright, similar to previous versions.
Observed result
Fog in caves is now bright, resembling sky color despite being underground.
Attachments
Comments 4
Here’s also an example of rain affecting underground env fog which well, shouldn’t be the case since rain doesn’t reach caves.
[media][media]
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After consideration, the issue is being closed as Working as Intended.
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This is related to, but arguably not the same as MC-118103, since that report covers skybox and render distance fog.
Here it could be fixed by adjusting the fog alpha so that it isn’t visible when sky light isn’t present, might be wrong though.