Pathfinding is fundamentally flawed (it strictly follows the grid)
I will say right now that both MC-12427 and MC-4661 are included in what I am about to report. However, I am reporting exactly what the problem is, how they are in reality the same issue, examples of other pathfinding issues which also occur, and how it could all be fixed with a single theoretical solution. It seems sort of conceded to ask if they could be consolidated into this report, but I feel like this single one is more constructive than a bunch of little ones out there which are all symptoms of the same bug.
The problem
The problem with the pathfinding in Minecraft is that is uses a strictly grid-based system. This would be okay except that collisions are not as strictly grid-based. Entity movement accounts for this, but pathfinding does not. The consequences of this are far reaching. Basically there are many ways in which an entity may conclude that it cannot move when in reality it can and vice versa. Fixing this bug would make farming less frustrating and hiding from monsters much harder. Let me explain each of the four images inside the larger image I posted.
1. Mobs (the creeper) get stuck in northwest corners
This is a combination of things. For one thing, entities begin pathfinding from their northwest corner instead of their center. For another, they do not take into account collisions properly. This means the creeper pictured begins his pathfinding from inside the corner fence. This creeper believes he can travel both north and west because it is air, and he cannot travel either south or east because they are fences. All four of these assertions are wrong. If he were to analyze collisions instead of just the grid he would know this.
2. Mobs are incapable of passing through half slab gaps
Some people like and utilize this, but it is a flaw. The creeper knows he can pathfind through the center of the hole, but reasons he is too tall to put his feet through the center and his head through the half slab. This is false. He does not take into account where his feet will land, and the same can be said about his head.
3. Mobs, especially small ones, get stuck inside walls
The picture is a special case in which the sheep has his northwest corner inside a wall. He can clearly step back and walk through the opening in the fence to my character, but he believes the fastest way is to walk through, because he is already "inside" the fence and does not take collisions into account. This same thing will happen with small entities far more frequently because their entire collision box can fit inside the fence block. This makes it a pain to lead animals along/through fences and other thin walls.
4. Mobs cannot navigate through gaps between blocks
This is the same issue as the creeper who cannot walk through the half slabs but in the x and z dimensions. If the chicken were to acknowledge the size of its bounding box and which blocks it would collide with, it could reason that it is possible to fit through the gap.
More details
It has recently come to my attention that small entities like chickens cannot pathfind out of fence corners even if they are told they can pathfind literally anywhere. This is because they cannot draw a vector out of the fence wireframe without concluding they will collide with it.
Theoretical solution
Ideally, if the code could be more double-based, relying on the actual bounding box, this problem would be fixed in all instances. But, unfortunately, that would likely require a significant amount of processing. Instead, it is probably best to add more conditions to the code which allow pathing along but not through fences.
At the very least, changing pathfinding so that entities begin from their center should fix situations 1 and 3 (MC-12427 and MC-4661 respectively) for the majority of creatures (everything but babies, silverfish, and chickens).
Linked Issues
is duplicated by25
MC-11614Mobs don't walk throught 2 block high door waysDuplicateMC-23671Cow Mob Path Finding BlockedDuplicateMC-56317Silverfish/Endermites/Cave Spiders not pathfinding through half-slabs (DUPLICATE)DuplicateMC-83644Mob pathfinding AI gets confused with glass panesDuplicateMC-95323fences, carpets and mob aiDuplicateMC-105078Mobs unable to jump on the carpetDuplicateMC-109393Llamas cannot climb properly, and constantly fall.DuplicateMC-119232Villagers cram into a certain cornerDuplicateMC-120034Villagers can't walk on carpets in a two-block high house.DuplicateMC-120048villagers can't go through doors with carpets in front of them.DuplicateMC-124539mob path finding wraps around the edges of blocks that do not obstruct its path to the playerDuplicateMC-170368Silverfish react weirdly around slabs.DuplicateMC-188959Zombies cannot go through carpet and blockDuplicateMC-188997Tamed cat's pathfinding breaks when near a a villager house with glass pane.DuplicateMC-190227Mobs can't pathfind through fence corner gapsDuplicateMC-190326Infernal mobs strangely fight at the distance between the holes.DuplicateMC-196974Mobs cannot move through bamboo.DuplicateMC-200247Silverfish cannot hit players that are next to iron bars/glass paneDuplicateMC-201009Rabbits breakingDuplicateMC-262922Mobs cannot pathfind between walls and fencesDuplicateMC-265930Mob doesn't move/pathfind closer to the fence to hit the player, even if they would be able to hit the player if they didDuplicateMC-267501Mobs with high value of generic.step_height are unable to step up fence or wallDuplicateMC-279867Villagers are not recognizing the fence gate as a path they can takeDuplicateMC-1606Mobs unable to move in slabbed houseDuplicateMC-3149Mobs do not realize that they can move between fence posts next to nether brick fence.Duplicaterelates to9
MC-12427Mobs get stuck in the North-West corner of a fenceFixedMC-140545Pathfinding prefers North (negative Z) directionFixedMC-159932Bees not able to navigate through 4 stairs put together ConfirmedMC-249244Some mobs with medium hitboxes occasionally get stuck when passing through open doors
LowMC-262480Mobs jump when they get near chains, end rods, bamboos, lightning rods or pointed dripstoneLowMC-12549Odd mob "magnetised attraction" behaviourLowMC-7360Zombie cant get villager if the villager is in a window or standing in a corner of fencesIncompleteMC-31153Bias in passive mob AI - still results in self-stranding passive mobs, even with Northwest bug fixedAwaiting ResponseMC-104870Mobs can't pathfind up stairs if there's carpet at the bottomFixed
![[Mod] Les3awe](../../../data/avatars/users/79847.png){kind=small}
- Won't Fix
Daniel King- 79
- 38
- Confirmed
Normal- Mob behaviour
- collision fence north-west pathfinding pathing
1.5.1 - 1.16.3
1.5.1 1.5.2 1.6 1.6.1 1.6.2 1.6.4 1.7.1 1.7.2 13w47e 13w48a 13w48b 1.7.4 14w02c 14w03a 14w03b 14w05b 14w06b 14w07a 14w08a 1.7.5 1.7.9 14w18b 14w20b 14w21a 14w21b 1.8 1.8.1-pre3 1.8.8 15w43c 15w44a 15w46a 15w51b 1.9 1.9.1-pre3 1.10.2 1.12 1.12.2 1.14.4 1.15.2 20w12a 1.16-pre3 1.16-pre4 1.16-pre5 1.16-pre8 1.16.1 1.16.2-pre1 1.16.3
Created Issue:
Pathfinding is Fundamentally Flawed (it strictly follows the grid)
I will say right now that both
MC-12427andMC-4661are included in what I am about to report. However, I am reporting exactly what the problem is, how they are in reality the same issue, examples of other pathfinding issues which also occur, and how it could all be fixed with a single theoretical solution. It seems sort of conceded to ask if they could be consolidated into this report, but I feel like this single one is more constructive than a bunch of little ones out there which are all symptoms of the same bug.The problem
The problem with the pathfinding in Minecraft is that is uses a strictly grid-based system. This would be okay except that collisions are not as strictly grid-based. Entity movement accounts for this, but pathfinding does not. The consequences of this are far reaching. Basically there are many ways in which an entity may conclude that it cannot move when in reality it can and vice versa. Fixing this bug would make farming less frustrating and hiding from monsters much harder. Let me explain each of the four images inside the larger image I posted.1. Mobs (the creeper) get stuck in northwest corners
This is a combination of things. For one thing, entities begin pathfinding from their northwest corner instead of their center. For another, they do not take into account collisions properly. This means the creeper pictured begins his pathfinding from inside the corner fence. This creeper believes he can travel both north and west because it is air, and he cannot travel either south or east because they are fences. All four of these assertions are wrong. If he were to analyze collisions instead of just the grid he would know this.2. Mobs are incapable of passing through half slab gaps
Some people like and utilize this, but it is a flaw. The creeper knows he can pathfind through the center of the hole, but reasons he is too tall to put his feet through the center and his head through the half slab. This is false. He does not take into account where his feet will land, and the same can be said about his head.3. Mobs, especially small ones, get stuck inside walls
The picture is a special case in which the sheep has his northwest corner inside a wall. He can clearly step back and walk through the opening in the fence to my character, but he believes the fastest way is to walk through, because he is already "inside" the fence and does not take collisions into account. This same thing will happen with small entities far more frequently because their entire collision box can fit inside the fence block. This makes it a pain to lead animals along/through fences and other thin walls.4. Mobs cannot navigate through gaps between blocks
This is the same issue as the creeper who cannot walk through the half slabs but in the x and z dimensions. If the chicken were to acknowledge the size of its bounding box and which blocks it would collide with, it could reason that it is possible to fit through the gap.Theoretical solution
If mobs were able to pathfind through blocks with abnormal collisions in the same way as they calculate movement (going as far as their bounding box will allow), all of these problems should be solved. However, this would require a substantial rewrite of the pathfinding code, possibly changing it to entirely double based. I started to mess with it myself but it is horribly difficult to read, even with MCP's rough translation. I will need to do a lot more tracing and variable renaming before I can understand exactly what needs to be done.I have been thinking of an alternative to rewriting the pathfinding to entirely double based code. If the pathfinder kept a little bounding box which represented where the entity was going (it seems to attempt essentially the same thing with a path point) and pushed it along like it was actually moving through blocks with odd collision boxes, it could set path points inside of fences and other partial blocks only when it is possible to move there. It should only have to make the calculations in circumstance when it comes into contact with said blocks. Then, once it concludes the space is passable, the vector stuff the code already does should make it move in a straight line.
At the very least, changing pathfinding so that entities begin from their center should fix situations 1 and 3 (
MC-12427andMC-4661respectively) for the majority of creatures (everything but babies, silverfish, and chickens).Environment
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relates to
I will say right now that both
MC-12427andMC-4661are included in what I am about to report. However, I am reporting exactly what the problem is, how they are in reality the same issue, examples of other pathfinding issues which also occur, and how it could all be fixed with a single theoretical solution. It seems sort of conceded to ask if they could be consolidated into this report, but I feel like this single one is more constructive than a bunch of little ones out there which are all symptoms of the same bug.The problem
The problem with the pathfinding in Minecraft is that is uses a strictly grid-based system. This would be okay except that collisions are not as strictly grid-based. Entity movement accounts for this, but pathfinding does not. The consequences of this are far reaching. Basically there are many ways in which an entity may conclude that it cannot move when in reality it can and vice versa. Fixing this bug would make farming less frustrating and hiding from monsters much harder. Let me explain each of the four images inside the larger image I posted.1. Mobs (the creeper) get stuck in northwest corners
This is a combination of things. For one thing, entities begin pathfinding from their northwest corner instead of their center. For another, they do not take into account collisions properly. This means the creeper pictured begins his pathfinding from inside the corner fence. This creeper believes he can travel both north and west because it is air, and he cannot travel either south or east because they are fences. All four of these assertions are wrong. If he were to analyze collisions instead of just the grid he would know this.2. Mobs are incapable of passing through half slab gaps
Some people like and utilize this, but it is a flaw. The creeper knows he can pathfind through the center of the hole, but reasons he is too tall to put his feet through the center and his head through the half slab. This is false. He does not take into account where his feet will land, and the same can be said about his head.3. Mobs, especially small ones, get stuck inside walls
The picture is a special case in which the sheep has his northwest corner inside a wall. He can clearly step back and walk through the opening in the fence to my character, but he believes the fastest way is to walk through, because he is already "inside" the fence and does not take collisions into account. This same thing will happen with small entities far more frequently because their entire collision box can fit inside the fence block. This makes it a pain to lead animals along/through fences and other thin walls.4. Mobs cannot navigate through gaps between blocks
This is the same issue as the creeper who cannot walk through the half slabs but in the x and z dimensions. If the chicken were to acknowledge the size of its bounding box and which blocks it would collide with, it could reason that it is possible to fit through the gap.
Theoretical solution
If mobs were able to pathfind through blocks with abnormal collisions in the same way as they calculate movement (going as far as their bounding box will allow), all of these problems should be solved. However, this would require a substantial rewrite of the pathfinding code, possibly changing it to entirely double based. I started to mess with it myself but it is horribly difficult to read, even with MCP's rough translation. I will need to do a lot more tracing and variable renaming before I can understand exactly what needs to be done.I have been thinking of an alternative to rewriting the pathfinding to entirely double based code. If the pathfinder kept a little bounding box which represented where the entity was going (it seems to attempt essentially the same thing with a path point) and pushed it along like it was actually moving through blocks with odd collision boxes, it could set path points inside of fences and other partial blocks only when it is possible to move there. It should only have to make the calculations in circumstance when it comes into contact with said blocks. Then, once it concludes the space is passable, the vector stuff the code already does should make it move in a straight line.
At the very least, changing pathfinding so that entities begin from their center should fix situations 1 and 3 (
MC-12427andMC-4661respectively) for the majority of creatures (everything but babies, silverfish, and chickens).I will say right now that both
MC-12427andMC-4661are included in what I am about to report. However, I am reporting exactly what the problem is, how they are in reality the same issue, examples of other pathfinding issues which also occur, and how it could all be fixed with a single theoretical solution. It seems sort of conceded to ask if they could be consolidated into this report, but I feel like this single one is more constructive than a bunch of little ones out there which are all symptoms of the same bug.The problem
The problem with the pathfinding in Minecraft is that is uses a strictly grid-based system. This would be okay except that collisions are not as strictly grid-based. Entity movement accounts for this, but pathfinding does not. The consequences of this are far reaching. Basically there are many ways in which an entity may conclude that it cannot move when in reality it can and vice versa. Fixing this bug would make farming less frustrating and hiding from monsters much harder. Let me explain each of the four images inside the larger image I posted.1. Mobs (the creeper) get stuck in northwest corners
This is a combination of things. For one thing, entities begin pathfinding from their northwest corner instead of their center. For another, they do not take into account collisions properly. This means the creeper pictured begins his pathfinding from inside the corner fence. This creeper believes he can travel both north and west because it is air, and he cannot travel either south or east because they are fences. All four of these assertions are wrong. If he were to analyze collisions instead of just the grid he would know this.2. Mobs are incapable of passing through half slab gaps
Some people like and utilize this, but it is a flaw. The creeper knows he can pathfind through the center of the hole, but reasons he is too tall to put his feet through the center and his head through the half slab. This is false. He does not take into account where his feet will land, and the same can be said about his head.3. Mobs, especially small ones, get stuck inside walls
The picture is a special case in which the sheep has his northwest corner inside a wall. He can clearly step back and walk through the opening in the fence to my character, but he believes the fastest way is to walk through, because he is already "inside" the fence and does not take collisions into account. This same thing will happen with small entities far more frequently because their entire collision box can fit inside the fence block. This makes it a pain to lead animals along/through fences and other thin walls.4. Mobs cannot navigate through gaps between blocks
This is the same issue as the creeper who cannot walk through the half slabs but in the x and z dimensions. If the chicken were to acknowledge the size of its bounding box and which blocks it would collide with, it could reason that it is possible to fit through the gap.More details
It has recently come to my attention that small entities like chickens cannot pathfind out of fence corners even if they are told they can pathfind literally anywhere. This is because they cannot draw a vector out of the fence wireframe without concluding they will collide with it.Theoretical solution
Ideally, if the code could be more double-based, relying on the actual bounding box, this problem would be fixed in all instances. But, unfortunately, that would likely require a significant amount of processing. Instead, it is probably best to add more conditions to the code which allow pathing along but not through fences.At the very least, changing pathfinding so that entities begin from their center should fix situations 1 and 3 (
MC-12427andMC-4661respectively) for the majority of creatures (everything but babies, silverfish, and chickens).
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Pathfinding isFundamentallyFlawed (it strictly follows the grid)Pathfinding is fundamentally flawed (it strictly follows the grid)
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@Dranitsin Roman
I've been working on this a while, and I know what causes the problem. Frequency goes up with population and smaller spaces only because the number of chickens which come into contact with fence goes up. Play Minecraft for a few days and a few animals will escape. It is random chance which lets them escape and it has not been reduced. However, a few weeks ago I began working on this and I have a fix for 1.5.2. If Mojang addresses the problem just as I did, or even in a better way if they can think of one, it will resolve the issue for normal farms almost certainly. However, from what I have witnessed and read directly from the code, in 1.6.2 nothing which causes animals randomly to escape over time has been resolved. (see my previous post for causes and how I fixed them) If you have not been experiencing issues with this yet: congratulations, I am happy for you.
As for the chickens getting stuck in fence corners, that is a pathfinding bug I am also currently looking at the code for. I have it all explained on MC-21109.
I am sorry if I come off as irritable, but I have not played Minecraft in quite a while due to my very large farm being impossible to maintain. I do not have 200 chickens shoved in a 4x4 space, but any number of entities in any space will eventually phase through a wall. Every time I play the game I must spend literally fifteen minutes to half an hour placing different varieties of sheep in their pens, checking multiple floors and fighting with pathfinding to put them back in their pens.
@ANBO Motohiko
No, that is a problem with core path-drawing methods, explained in MC-21109, which honestly is the same problem as MC-12427 and MC-4661 (which have the same cause in the code), but explained in more detail for more situations. In that bug, an entity is trying to path from inside a fence. In this bug the random destinations animals choose to move in tend to be weighted northwest of it. Both bugs are annoying and should be fixed however.
@Kumasasa
You are somewhat right. Actually, the exact source for this (and MC-4661) is explained in a separate bug report I made (MC-21109) which encompasses quite a few different issue all caused from the same flaw that pathfinding is heavily grid-based while movement is not. It is not one little bug but rather a conceptual flaw in the coding that sometimes mobs can pathfind when they cannot move somewhere and cannot pathfind when they can move somewhere. Obviously, whether a mob thinks it can move and whether it can move should always agree. The reason no mobs (including large ones) can pathfind out of northwest corners is because their pathfinding algorithm begins pathfinding from the block which contains their minimum x and z bounding box coordinates. Then, beginning from inside the fence block, they pathfind in a totally grid-based way and conclude their only possible paths lead through the fence they are stuck against.
Duplicate of MC-21109
This issue relates to MC-21109.
Thank you for your report!
However, this issue is a Duplicate of MC-21109.
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This issue duplicates or relates to MC-21109.
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MC-21109 covers that for other mobs
Thank you for your report!
However, we are already tracking this issue, and this report is a Duplicate of MC-21109, which is a report that has not been resolved yet.
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Thank you for your report!
We're tracking this issue in MC-21109, so this ticket is being resolved and linked as a duplicate.
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Thank you for your report!
We're tracking this issue in MC-21109, so this ticket is being resolved and linked as a duplicate.
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Thank you for your report!
We're tracking this issue in MC-21109, so this ticket is being resolved and linked as a duplicate.
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Thank you for your report!
We're tracking this issue in MC-21109, so this ticket is being resolved and linked as a duplicate.
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Thank you for your report!
However, we are already tracking this issue, and this report is a Duplicate of MC-21109, which is a report that has not been resolved yet.
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Thank you for your report!
However, we are already tracking this issue, and this report is a Duplicate of MC-21109, which is a report that has not been resolved yet.
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This was inspired by MC-21109 but thanks for the heads up.
If you have a mob near a chain sometimes they will jump
It seems like they think they are full blocks (this can be supported by the fact they won't leave the chains, but I doubt this is fixable per MC-21109). When they get too close, they jump around a lot.
Video example: https://www.youtube.com/watch?v=eUz9D_hK2zo
Duplicate of MC-21109.
![[Mod] Jiingy](../../../data/avatars/users/91802.png){kind=small}
This issue duplicates MC-21109 which was marked as Won't Fix.
The hole between fences is 12/16th of a block, that's not a bug (it matches the fence's visual width). Pathfinding doesn't allow mobs to go through it though, only when forced through (just like you did in the video), because pathfinding is locked to the block grid (MC-21109), so no, that hole doesn't allow them to get out (by themselves).
This is a change request of either the structure, or fence width.
This issue seems to be due to MC-21109
Cannot reproduce:
2023-12-22_16-50-03.mp4
The entity can step up, it just does not pathfind over the fence. This is likely due to MC-21109. Otherwise, the described behavior of mobs not being able to pathfind towards (and by result, over) fences woud be MC-265930.
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Would MC-21109 describe your issue?
This issue is being temporarily resolved as Awaiting Response. Once the requested information has been delivered, the report will be reopened automatically.
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PLEASE.
Thank you for explaining – and showing with simple pictures – exactly what's going on.
PLEASE, Mojang, this and 2025 – please make these, and similar issues, the focus of your next patch level. Yes, I'm asking for 1.7 to be the raid release (raid = bug spray)
Can confirm.
Is this still a concern in the current Minecraft version? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.
I tested this bug in Creative Singleplayer also and can confirm it still exists in 1.6.2.
Do you have any idea what the computational cost of pathfinding is? A lot of games pre-calculate and store pathing information for the terrain in order to reduce the cost of finding a path. There are certainly improvements that could be made, particularly to solve the sort of problems you mention, but you're oversimplifying the problem a great deal.
@Torabi
No, I have no prior knowledge of the computational cost of pathfinding, but I do have a decent guess. And I do understand the challenges of pathfinding in a dynamic environment.
I do think I oversimplified the theoretical solution. Having read the pathfinding code thoroughly now, I am disappointed to say that I doubt it can function perfectly ever. Changing it from int based to double based would require exponentially more points, memory, etc. I think the only way the problem has any chance of being solved in a remotely optimal way is by continually adding even more conditions to the code that basically say "in this very specific situation, do this".
Is this still a concern in the current Minecraft version 1.7.2 / Launcher version 1.3.4 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.
Yes, this affects all versions up to the most recent snapshot, 13w48b. This bug would require a very significant code change to fix.
Is this still a concern in the current Minecraft version 1.7.4 / Launcher version 1.3.8 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.
This affects all versions up to snapshot 14w03b.
I can confirm in 14w08a with the stuck in NW corner part
Is this still a concern in the current Minecraft version 14w18a / Launcher version 1.3.11 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.
There has been no rewrite of the pathfinding system. I can still observe this issue in 14w18b.
This happens with silverfish, cave spiders and endermites as of snapshot 14w21b.
I may be experiencing something similar to this in 14w snapshots (21b,25a,25b). I have two snow golems (which are NBT tagged to be invincible). They WERE attacking a baby Zombie with snowballs, so I named the baby so it wouldn't despawn. This all was happening near a corner of Nether brick fence, and somehow the little Zombie was pushed into the corner. The Zombie does not move (and being a baby it is immune to sunlight) and the golems aren't throwing stuff at it. This may be a result of how small baby Zombies are, because they can fit entirely into the hit box of a corner fence.
I think the fence is a northeast corner. I can attach screen shots if needed.
I think that this shows a fundamental bug in the AIs of at least 2 mobs.
ggxl, that sounds like
MC-7360.I looked at that bug, and it is basically the same as this one, but this bug report addresses the root cause (pathfinding is flawed). To be more specific, the zombies have the goal of reaching a villager that is in a space occupied by a partial block like a glass pane, fence, or half slabs. Zombie pathfinding (like every other mob's pathfinding) isn't capable of utilizing the empty space that a partial block doesn't use, so the zombie behaves as if the entire space is solid and impassable.
I think it warrants a "relates to" label.
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.
Of course it is. It's pretty obvious. Reopen.
Reopened, thanks
Confirmed for 15w43c & 1.8.8.
Confirmed for 15w44a.
Confirmed for 15w46a
Can confirm this for carpets on fences.
Partly confirmed for 1.9.1-pre3
All fence problems (1, 3 and 4 pictures) are fixed, slab problem is still there. Also I found another problem (2016-03-19_13.04.06.png)
I suppose in the new picture no mob moves on its own?
Also noticed lately that mobs don't go through open iron doors (creepers and zombies mainly).
More observation of path-finding errors:
I observed mobs not realizing they can walk around a fence post. They can see me, but they stay behind the post and never come closer to me, even though they could.
I've included screenshots of various mobs getting stuck in the same place like this.
Granted the screen shots are of range-attack mobs like witches and skels, but creepers and zombies were also getting hung up there. I just failed to screen shot the zombies and creepers doing it. But hung up where they are, even the range attacks were useless. The witch's bottles were breaking on herself, and the skel arrows couldn't get past the fence post.
This is still happening in 1.14.4.
Still in 20w12a.
Still in 1.16 Pre 3
I think this might fit better on the suggestion/feedback site rather than the bug tracker?
I don't believe so, because it causes passive mobs to wander away in the same direction or bunch up in corners of fenced in areas, and that is clearly a bug/unintended behavior.
20w46a