Jonathan Gilbert
Assigned
Reported
Comments
Okay, I've just reproduced it. Here are the steps I followed:
New Superflat world, I used the Redstone Ready preset but I'm sure it doesn't matter.
Construct a column two blocks wide and 93 blocks tall. Again, exact height probably doesn't matter, I just wanted it to be in the same ballpark as my original construction. The two blocks of width should be different Z coordinates, same X.
Face the pillar facing west ("towards negative X"). Not sure if this is important, but MC-73193 mentioned it, so I decided to go with it.
Place signs every 4 blocks up the left side of the pillar (higher Z). Again, this precise detail is probably not important, but I mimicked my original design and placed a number in each sign to represent a floor number, as in my 20-storey building.
Clone the right side of the pillar (with no signs), plus the block of air in front where the signs are on the left side, overtop of the left side. All the signs disappear.
When re-placing the signs, the text that was previously assigned magically reappears.
I tried saving and re-opening the world, and the text went away, so it isn't actually persisted in the world files (or if it is, it fails to load back in).
This may be the same underlying bug as in MC-73193, but I'm reporting it in the context of a clone command that does not use the "move" clone mode.
I had a thought that it might be the result of multiple signs being overwritten with air in one command, but I gave that a try and it did not reproduce it. Not sure what else to try... I'd love to give you a solid repro on this one. 😛
Is there any possibility outdated video drivers could have caused this logic error..?? I did have a separate issue to do with /clone and /fill, serious visual artefacting as described in MC-62958, and it was fixed by updating my video drivers. It seems unlikely to me that a change in video drivers could cause a change in the way the sign-placing code behaves, but the visual glitches themselves were strange & wild in the most unlikely ways too...
Hmm, okay, I'm trying to reproduce this and haven't succeeded yet. However, I did experience it repeatedly while actually playing. I had constructed a flight of stairs for a 20-storey building, and used /clone to replicate the 2nd floor's stairs up to the 20th storey. Then, I manually placed signs indicating which floor each one was. When I tried the stairs, however, I realized there was a mechanical fault with them, so I redid them and /cloned over the space they had been in. After doing this, all the signs were gone, but when I went to re-place them, wherever they had already been before, the floor number was already there.
This happened on west-facing walls, in case that matters...
Yep, does appear to have fixed it. 🙂
Interesting that for me, it was specifically /clone and /fill that seemed to trigger it. I always knew when it had screwed up because the result of the operation didn't appear on-screen immediately. No other artefact appeared at that point, but then disconnecting and reconnecting produced the crazy visuals, which would continue until a full client restart. Very specific. I wonder how it happened, and how the video driver was the cause...
Installing latest drivers now, will update with results.
The attached screenshots were all taken within a few seconds of one another in roughly the same location in the world, just rotating the point of view.
Okay, I will do that. Just for completeness, I have a couple of additional observations:
1) A reboot did not correct the issue.
2) Using Alt-Tab to switch away does correctly switch it to a windowed view.
I wonder if it is related to new code added for the Twitch.tv integration. In any case, I will pursue the matter further at the Support Centre. Many thanks 🙂
I just reproduced it in 15w45a.