While making a custom model I noticed some unusual artifacts when making two thin faces in the same plane, To further test this I created the attached Resource Pack which renders each pixel in the default 16x16 textures as mini-cubes, overkill; but this re-creates the issue I saw earlier perfectly and it is much more pronounced.
Additionally it also shows that the issue only affects the top & bottom faces.
I also tested with and without "Smooth Lighting" the issue is only visible with "Smooth Lighting"
I included a screenshot of the issue demonstrated via the resource pack, besides the custom resource pack to demonstrate the issue all game settings were default, and was a fresh installation.
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is duplicated by 1
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Comments 4
This is because each cuboid part of a model renders smooth lighting as if it were a full block. This is unfortunately an inherent problem from the rather deeply coded smooth lighting algorithm, and would require a whole rewrite of a lot of code to fix. However, I personally think smooth lighting should be fixed, as it's not really been changed one bit since it was originally implemented.
I personally don't believe this is as difficult an issue to fix as you believe, it only affects two faces of the cube, if they can get 4 out of 6 to work fine, I'm sure its something that can be fixed by tracking down the differences and sorting it it out.
Confirmed for
1.8.4