The resource pack attached to MC-212630 offers a complete fix for this issue. Mojang have my full permission to (and are encouraged to) replace the affected vanilla model files with the contents of the resource pack.
The bug
Melon and pumpkin stems appear considerably darker in-game than they should due to missing ["shade": false] parameters in their model files.
How to reproduce
Plant melon or pumpkin seeds
Have the seeds grow to their full size
Notice how the stem looks somewhat dark. If you look at the point where the two planes intersect, a clear boundary can be seen where the shading changes, which does not apply to other crosses. this can be seen to not be a texture issue by looking at both of the planes individually, which reveals they are lit differently.
Current appearence:
[media][media]
Expected appearance:
[media][media]
How to fix
The resource pack attached to MC-212630 fixes this issue completely, alongside fixing multiple other issues with the stem model.
Notes
While this was one of the cases listed in MC-68302, a 2014 ticket which was resolved as Works as Intended, I'm still reporting this independently of it for a multitude of reasons:
This bug makes melon and pumpkin stems very inconsistent with all other crops, as well as all other cross-shaped plants, as absolutely none of these use shading.
This behaviour is an unannounced change from 1.7 and prior versions, as these all had the stem render without this problematic shading.
MC-68302 lumped several different model issues into one ticket, which is very confusing, and a discontinued practice which is generally not recommended much in more modern times. The individual issues in such tickets deserve a chance on their own as to allow for cleaner bug reports, fixes, communication and feedback, analyses, and so on.
Two other issues split off from MC-68302, namely MC-129826 and MC-214662, are still considered valid issues.
It just looks downright unsightly.
Related issues
Attachments
Comments
migrated
ampolive
Can confirm.
ampolive
Attached an image of how it used to look in 1.6.2.
Moesh
Marking this a dupe because this is more an effect than the root problem. Even if the root bug, MC-221307, was fixed this would not look the way you expect it to. For this, we would consult with our artists to make a decision.
muzikbike
Going to have to strongly disagree on this one. While MC-221307 may indeed manifest on melon and pumpkin stems, the core issue here is that they shouldn't be shaded at all, but are.
Stems were converted over to use models in 1.8 in much the same way as other crosses (e.g. flowers, grass) were, and changes in 14w25a resulted in the majority of blocks being shaded even when they should not be. While the issue was soon fixed in later 1.8 snapshots for most of these crosses, stems were left out of this fix.
I'd recommend booting up an instance of 1.7.10 and then placing down a dandelion, then planting a melon or pumpkin stem next to it and then bonemeal it to its fully grown state. Then load this world in snapshot 14w25a (in its unstable 2014 glory), taking note of the now dark appearence of both of these plants (the stem will also be affected by MC-58136, but that's a separate issue which was fixed soon afterwards; just focus on the shading). Upgrading this world to the full release of 1.8 should reveal the dandelion to be fully bright again like in 1.7.10, but the stem will still be dark. The fact that the dandelion (and most other crosses) were fixed through minor tweaks to the model file, but melon and pumpkin stems were not despite these same fixes also working for them, is what this issue concerns.
muzikbike
This issue still affects 22w16b and should be reopened, since it isn't a duplicate at all. MC-250076, which is effectively the opposite of this issue for another block, was triaged, so this resolution now makes even less sense.
muzikbike
I still maintain that this resolution is incorrect; MC-129826, which is the exact same issue affecting potted plants, was fixed in 24w33a. I do not understand why melon and pumpkin stems shoukd be treated differently, as the issue is clearly with the model file rather than the game's rendering engine (and the models can be extremely easily fixed).
Mega611
Can confirm 1.21.4.