Painting offset 1 block to the supporting wall when painting entities get unsupported NBT tags

https://www.dropbox.com/s/33u5vxfvc3ja6e9/bug.zip?dl=1

Were these pictures placed with mcedit?

Can not confirm with the attached world

@Mustek no, they're placed by hand.

Below is a copy/paste of the comment I left on MC-72888, which appears to be a duplicate listing of the same bug. Kumasasa requested that I leave this comment here as well:

Confirmed for 1.8.6. This appears to be related to using the "NoAI" command. This bug was constantly occurring when I had a 20hz fill clock in my spawn chunks running the following command:

/entitydata @e {NoAI:1}

and it stopped as soon as I deactivated that clock.

Description of bug:

Some (but not all) placed paintings appear to "dance" around the locations where they were placed, alternating at an irregular rhythm (perhaps averaging 2 seconds between each state change) between 3-4 states, sometimes appearing to be where they were actually placed, sometimes appearing to be placed above, below, to the sides of, or in front of where they were actually placed, sometimes appearing to be imbedded in other blocks or placed in the air with no backing. All paintings that change states do so at same times, and all paintings that change states with the same facing appear to move in the same direction at the same time.

Attached are 3 examples, each with 3 screenshots showing the states that those particular paintings cycle through when the clock that activates the NoAI command is active. I also attached a report from a crash that I forced in a world where this issue was occurring.

Turning off all of the redstone mechanics does indeed seem to stop the misbehaviour, in my case it's "CustomNameVisible" instead of "NoAI" though.
I guess this might be a general issue with NBT data for paintings, they can't store the information anyway.
Repeatedly trying to set the CustomNameVisible tag to 1 will cause the painting to seemingly disappear until next login ("/say @e" will still list it).

PS:
When shutting down the redstone circuitry while the painting is in an 'incorrect' state, it won't 'recover' until you relog.

Edit: added 2 screenshots (20 Hz clock, executing

/entitydata @e[type=Painting] {CustomNameVisible:1}

)

1 by 1 sized paintings seem not to be affected btw.

@Mario Welzig: Good observation! You just made me realize that I haven't seen any 1x1 paintings be affected by this issue either.

Created MC-80956, which might be associated with this one.

Can still not confirm with a 20 Hz clock and

/entitydata @e[type=Painting] {CustomNameVisible:1}

or

/entitydata @e {NoAI:1}

Can anyone create a new flat world with only a clock and a painting showing that effect ?

Just created a new world and hooked up a 20 Hz clock to a command_block executing

/entitydata @e[type=Painting] {CustomNameVisible:1}

The result was that the 2 paintings turned invisible until i relogged.

The world:

PS: Technically, "CustomNameVisible" is not an invalid tag, but it's only stored if you apply a "CustomName" tag first (new screenshot).

I had the same experience that Mario reported above. When I created a superflat world and tried to duplicate the "dancing paintings" issue there (

), I instead had most of the paintings turn invisible, so there must be some other factor at play that determines which of the symptoms appears.

I also tried testing the issue on SethBling's "Building Game" map (http://sethbling.com/TheBuildingGame), which is the map on which this issue was reported in MC-72888, and also had the paintings I placed disappear there. But we know from Sethbling's video (http://youtu.be/VtyUKFu6bl8?t=5m53s) that the offset issue can also occur on that map, so maybe the /entitydata command that affects paintings needs to run certain number of times before you get the affect of paintings appearing to be in positions that are offset from where they're really placed, and before that point you get the disappearing effect, or perhaps the world needs to be a certain age or greater.

If you'd like to see a world where you can see the offset effect, here's a download link for the world in which I first experienced the issue, and from which I took the screenshots above:

In that world, the command block that's giving the /entitydata command is located at: 68.5 4.5 -1277.5, if you'd like to verify that breaking that block makes the issue go away.

Also, it should be noted that the effect typically takes around 7 seconds or so after logging in, and after placing a painting on which you want to see it manifest itself on, before it actually manifests itself.

I'm noticing that this issue is still marked at "unconfirmed". If I'm understanding your confirmation standards correctly, it should be easy to confirm by logging in to the attached

world, waiting 10 seconds or so for the issue to manifest itself, then breaking the command block with the "/entitydata" command at x:68.5, y:4.5 z:-1277.5, and then going back to the paintings to see that the issue is no longer present.

Confirmed with Clash of Elements

Still occurs in current snapshot 15w34d.