[MC-126772] Underwater fog doesn't hide edge of chunks correctly at low render distances

The bug

The underwater fog doesn't hide chunk edges correctly, causing unwanted visual effects when the player has a low render distance. If you're below the sea level (most of the cases) you'll be able to see the black background, unlike the surface fog rendering the background with a light color hiding chunk edges seamlessly.

If you're underwater above the sea level, you'll see a blue background instead of the black section, which looks a bit better but you can still see the edges, and this is due to the skybox rendering overlapping the fog causing other issues like being able to see the sun underwater (MC-152504).

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Undewater with 16 chunk render distance (fog covers everything):

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Underwater with 8, 4, 2 chunk render distance, limits are visible:

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Surface to underwater transition at 2 render distance:

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Notice how in the first image everything looks fine, then in the second image the fog covers almost everything of the background like it should, then we have the third image where after some seconds the skybox is visible.

Linked issues

relates to 1

MC-152504 Sky (notably at sunrise and sunset) overlaps fog underwater Reopened

Attachments

Comments 5

Oval 2018-09-23T23:44:38Z

Confirmed for 1.13.1.

syarumi 2021-06-06T05:37:55Z

Affects 1.17 rc1. I believe this one talks about the black missing section below the sunset? while MC-152504 emphasizes the skybox. Both might be the same issue tho.

Edit: Actually, that "black section" is still the skybox, but it being visible is because of unloaded chunks not being hidden by the underwater fog like how it works with the surface fog (probably due to the underwater fog having a reduced radius), making it very noticeable at low render distance.

syarumi 2021-07-01T21:08:35Z

Can i request ownership? i'm willing to modify the ticket to not be confused with MC-152504.

wobst.michael 2022-01-23T09:32:54Z

So in how far has this been fixed since MC-152504 is still a thing?

Timur Nazarov 2022-01-24T15:16:59Z

I did not fully understand your question.
There are 2 separate bugs with different causes. One was fixed, the second was not.
This one was caused by the fact that fog underwater was not connected to render distance at all. So when render distance was lower than "natural underwater fog" distance the chunk edge was clearly visible.
Now underwater fog is affected by render distance and there is no sharp chunk edge except for the case described in #MC-152504.