Description:
As the title says, upwards facing pistons - both normal and sticky - won't activate one block below the build limit.
I think this is definitely a bug, since pistons should still fit under the build limit when they're one block below it and extended.
Steps to reproduce:
1) Place a piston on level 255 - standing on (254 - looking at).
2) Place redstone block next to the piston.
Below is a screenshot of the bug:
[media]EDIT:
This bug also occurs at the bottom of the world when the piston is placed facing downwards on the second layer of the world.
For survival, with default world generation, this isn't a problem, but for creative worlds, it certainly can be.
Linked issues
Attachments
Comments 11
I understand your point, however it still feels like a bug to me, or at least an unintuitive feature, because for all intents and purposes, those pistons should be able to active, since there's valid room above/below them.
@unknown I get what you mean, and I also agree with @unknown, but putting this being potentially expected behaviour and thus potentially a bug aside, could you give me examples of when piston without a block below/above extending towards absolute build maximum (Sky/Void) would come in handy?
Again, while I understand that this could be seen as expected behaviour, fixing things like these just for the sake of it, when it has no use/benefits whatsoever (and doesn't break gameplay in some manner), seems like developer worktime invested into something that could be used elsewhere better (e.g. revamping the whole Redstone system).
From what we've seen in the past, it also doesn't seem to be advisable to have the Devs fiddle with the piston code at the current state of the code in totality, unless there'd be a really good reason to do so.
Of course, up to Mojang to decide, but I always get nervous when I see piston bugposts due to past experiences.
Edit: I remembered an old bugfix (2014), found it now: MC-58985
Blocks would get deleted past the build limit.
Hi there!
I understand your points, but this is still a valid bug. Take a look at MC-195544, for example. It's a hugely complex order of mobs on mobs in order to recreate the issue, but it still was a valid bug, marked as Mojang as Very Important and fixed in 1.16.2 Prerelease 1.
A quick example that I can think of is a redstone contraption requiring observers detecting a change in a block, and a one-tick piston could be used for that.
A possible solution is to have the game check if there is a block above the upwards-facing piston, and if there is, then it should not fire, but if there is not, then the piston should fire.
I can confirm in 1.16.1 and snapshot 20w30a.
Yes indeed, I thought of the same solution you suggested, but I don't know if this is expensive or also wise to do at this point in time, and some bugposts - as legit as they might be - just wouldn't hurt anyone if they wouldn't get fixed (for now, at least).
The bugpost you linked is something completely different.
As for the example you brought up: I didn't mean something as simple as that, but rather a more complex contraption that has its very good reasons to be so close to the build limit, that it would undoubtedly need to be at exact that Y-level, and couldn't be just 1 lower, to put it plainly.
Basically, a very good reason why the Devs should bother working on this bugpost, or especially fiddle with the piston code, which could hypothetically affect other behaviour.
I'll keep this post on my watchlist and am curious how it'll be resolved 🙂
@unknown I found this bug when I tested my piston elevator that goes up to build height, and noticed I wasn't pushed up to the very top.
But I do agree with you on that this is not a big issue, and really does not affect a large part of the game at all, and if fixing this would be messy and would potentially ruin pistons in some way, then it should be left well enough alone.
Thank you for your report!
However, this issue is a Duplicate of MC-69876.
It has been linked to this report. If you have additional information, please add it to that report.
Please search before reporting, as it's likely that one exists already.
Quick Links:
📓 Issue Guidelines – 💬 Community Support – 📧 Customer Support – 📖 Game Wiki
I think this is not a bug but a feature of the game. I cannot confirm this whatsoever but i think it's made like that to prevent them to push the block on top of them higher than the build limit. Cannot find any information about this tho.