[MC-1230] Players and mobs can fall through extending/retracting pistons

I tested your modification and it seems you only fixed mobs going through blocks. The main problem was having things fall through the wooden retracting/extending piston part.

17 more comments

fienxjox 2013-10-29T03:04:27Z

Don't know about 1.6.4, but I can confirm 1.7.2 / launcher 1.2.8

fienxjox 2014-01-23T18:17:08Z

Continued confirmation, 14w04a

Joe Person 2014-03-31T05:17:57Z

Confirmed 1.7.5 with my accidental duplicate https://bugs.mojang.com/browse/MC-52281

rydian 2014-10-18T15:38:33Z

Confirmed in 1.8.1-pre2.
http://gfycat.com/TatteredDeliciousDegu

DOMOHEAD 2014-10-18T16:22:47Z

This is because you can fall through block 36

Chris 2014-12-20T17:27:38Z

This also affects slime blocks moving with the piston head, when the piston is extending down or horizontally or retracting in any direction. But since it doesn't affect solid blocks, I'd say the problem isn't that we can fall through block 36, but that we can also fall through TileEntity{id:"Piston", blockId: minecraft:piston_head} and {id:"Piston", blockId: minecraft:slime}

KingSupernova 2015-09-12T10:04:40Z

Confirmed in 15w37a. Should be mentioned that it happens with any blocks being pushed by a piston, not just the arm.

Erik Broes 2015-09-14T07:57:13Z

This will be marked fixed in a snapshot near you soon.

Manuel 2015-09-16T14:48:42Z

Still happening in 15w38a..

CubeTheThird 2015-09-16T15:07:43Z

Can confirm for player, but not for mobs.

user-f2760 2015-09-16T15:40:23Z

I can also confirm for both plyer and skeleton (at least)

CubeTheThird 2015-09-16T17:41:43Z

I'm not entirely convinced that the remaining issue is actually a bug. Previously, if an entity is standing on a block, and a piston pushes it, it falls through the piston to the block below it. Now, instead of falling all the way through, it falls onto the "neck" portion, which is solid. Upon retracting the block, the player/entity is inside it, since the block is taller than the "neck", causing them to fall through. The same behaviour can be observed if the player stands on a slab, and is pushed by a full block.

Erik Broes 2015-09-16T18:23:59Z

Things will not get pushed up when they get stuck in a block. They will prefer to fall down.

I think the current behaviour is at least predictable 🙂

An_yMiner 2016-03-10T22:03:04Z

It's still a problem for every block that moves before the mob takes notice. Mobs fall through retracting pistons; Mobs and players can be pushed into blocks that started moving earlier in the same tick.

An_yMiner 2016-03-30T19:55:07Z

still in 1.9.2
https://youtu.be/LK6rZLBWRUg

user-f2760 2016-03-30T21:22:39Z

@unknown actually what you see there is MC-89030

An_yMiner 2016-03-31T13:25:39Z

@unknown [MC-89030] moves entities out of blocks, not into them.

user-f2760 2016-03-31T13:34:06Z

When retracting they do, see sethbling's video about it, this issue has been fixed, what you see is MC-89030

An_yMiner 2016-03-31T16:02:45Z

@sethbling's video: In order for a block to be able to be pushed the ones in front need to moved or destroyed. So when the piston extention gets pulled back, the piston base gets removed; Entities inside the extention are set infront of it. No surprise here.

What I'm complaining about is the behaviour of entities being moved into a position, where other blocks are:
Block started moving in tick t

	t <= -3	-3 < t < 0	t = -0	t = +0	0 < t < 3	3 <= t
Entity movement blocked	y	y	n	y	n	n

user-f2760 2016-03-31T16:13:16Z

when MC-89030 is fixed, and this is still an issue, then this will be reopened, not sooner as it's very likely the same issue as you experience

An_yMiner 2016-10-06T16:21:07Z

@@unknown fixed in Minecraft 16w40a

An_yMiner 2016-10-06T18:03:20Z

I just found out that shifting floors work again. (Mobs fall through moving blocks; Players don't fall but have trouble moving)