[MC-8340] Comparators do not update their state when blocking or unblocking a chest with a block on top Created: 25/Jan/13  Updated: 21/Aug/24

Status: Reopened
Project: Minecraft: Java Edition
Component/s: None
Affects Version/s: Snapshot 13w04a, Snapshot 13w07a, Snapshot 13w10b, Minecraft 1.5, Snapshot 13w11a, Minecraft 1.6.1, Minecraft 1.6.2, Minecraft 1.7.4, Minecraft 14w02c, Minecraft 14w03b, Minecraft 14w04a, Minecraft 14w04b, Minecraft 14w05a, Minecraft 14w05b, Minecraft 1.8.1, Minecraft 1.8.2-pre6, Minecraft 15w40b, Minecraft 1.10.2, Minecraft 16w38a, Minecraft 1.11.2, Minecraft 1.13-pre6, Minecraft 1.13-pre7, 1.15.2, 20w21a, 1.16.1, 1.16.2 Pre-release 1, 1.16.2 Release Candidate 1, 1.16.2, 1.16.3 Release Candidate 1, 1.16.3, 20w48a, 1.20.4
Fix Version/s: Snapshot 13w05a

Type: Bug
Reporter: DicoTheRedstoner Assignee: Unassigned
Resolution: Unresolved Votes: 20
Labels: None

Attachments: PNG File 2013-02-06_00.23.02.png     PNG File Chest not empty Blocked.png     PNG File Chest not empty.png     JPEG File With Block.jpg     JPEG File Without Block.jpg    
Issue Links:
Duplicate
is duplicated by MC-49652 Comparator Will Not Detect Covered Chest Resolved
is duplicated by MC-268154 Comparator does not update properly w... Resolved
Relates
relates to MC-120986 Comparators do not update correctly i... Open
relates to MC-28479 Chest interface not closed when chest... Open
relates to MC-100302 Comparators don't give output of bloc... Open
relates to MC-11434 Comparators don't update properly whe... Reopened
CHK:
Confirmation Status: Confirmed
Category:
Block states, Redstone
Mojang Priority: Low
Area: Platform

 Description   

I found this bug where comparators dont output any signal from a chest, when the chest has a block on top. I'm not sure if it's intended, but I thought I might as well post it. It allows for a cool clock like in the third screenshot, However the clock creates major lag spikes on servers after 1 minute or so, more lag than it should.
Since I don't seem to be able to upload screenshots, I uploaded them to imgur:
http://imgur.com/advoWtp
http://imgur.com/Fyh17O0
http://imgur.com/9q6GdZb



 Comments   
Comment by [Mod] Avoma [ 01/Dec/20 ]

Can confirm in 20w48a.

Comment by [Mod] j_p_smith [ 14/Aug/20 ]

moosefreak, that is MC-100302.

Comment by moosefreak [ 19/Jul/20 ]

Still an issue in 1.16.1, items can go into a chest via hoppers when a block is on top, but items can't be detected inside a chest when a block is on top.

Comment by [Mod] j_p_smith [ 21/May/20 ]

Confirmed in 1.15.2 and 20w21a.

Comment by Fabian Röling [ 13/Oct/16 ]

Is this now WAI because hoppers also can't interact with blocked chests?

Comment by KingSupernova [ 02/Feb/15 ]

Please don't repeat the horrible mistake of MC-108 and leave this extremely glitchy behavior in the game just because a few people find it useful. Bugs should be fixed, not left in the game to confuse and irritate every player that tries to build something. There are already enough inconsistent behaviors in the game, as more and more start to accumulate, the game will eventually become unplayable. It's just not worth it.

Comment by yut951121 [ 30/Jan/15 ]

This is still in 1.8.2-pre6, but fixing this bug would be very sad because lot of contraptions already made use of this

Comment by Galaxy_2Alex [ 25/Oct/14 ]

Is this still a concern in the current Minecraft version 1.8.1 Prerelease 3 / Launcher version 1.5.3 or later? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.

Comment by DicoTheRedstoner [ 11/Mar/14 ]

This turned out to be a really useful 'bug' so how about not fixing it and resolving it as 'works as intended'

Comment by Stephen Train [ 18/Mar/13 ]

Still occurring in 13w11a

Comment by GrygrFlzr [ 17/Feb/13 ]

Confirmed to still occur on 13w07a with all block updates (not just redstone). Reopened.

Comment by Randal Jones [ 16/Feb/13 ]

This issue has not been fixed as of 13w07a. My set-up is shown in two new pictures. The chest is half-full so the comparator should be lit, which it is when the chest is not blocked from opening. Next I place a block above the chest and the comparator remains on. But if I force the comparator to update by momentarily applying a signal to it's side the lights go off and stay off. When I remove the block above the chest the comparator output remains off until I either push the button again or simply open and close the chest; then the comparator lights up again. Because of the long redstone path, pushing the button when the chest is not blocked makes no difference because the low signal strength from the button is less than the signal from the half-full chest. Pushing the button only serves to force the comparator to update. (The screenshot from 05/Feb/13 makes it appear that the problem was fixed but it might simply be that the comparator has not updated.)

Comment by Mustek [ 05/Feb/13 ]

It seems like this has been fixed, see the new screenshot.

Comment by DicoTheRedstoner [ 25/Jan/13 ]

thanks ^^

Comment by GrygrFlzr [ 25/Jan/13 ]

Attached screenshots to issue.

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