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MC-142942

Collision boxes don't interact with walls correctly

The bug

19w08a and above :

Players don't interact with walls correctly.

-Players can have weird interactions with walls in water, by walking against a wall while pressing jump key, then keep walk against the wall without pressing the jump key. It is easier to reproduce if there is slimeblocks below water (

[media]

)

 

History :

19w07a :

/

19w06a :

/

19w05a :

-Slow falling against walls fixed, therefore double jump fixed.

-Interaction with walls in water not fixed (

[media]

)

19w04b :

-Interaction with walls in water not fixed (

[media]

)

-Walking on walls partially fixed, player now falls slowly when moving against a wall. 

[media]

 (player)/

[media]

 (mobs)

-You can now perform a double jump. This bug is very cool, you should consider making an enchantment for boots that acts exactly the same (slow fall if you're against a wall and be able to double jump). This enchantment could be spider related, maybe only obtainable in a chest hidden deep in these cobwebs that are around cave spider spawners in mineshafts. Video : 

[media]



 -This affects mobs. Videos : 

[media]

 (Zombie double jumping)/

[media]

 (Creeper double jumping)

19w04a :

Players and mobs hitboxes don't interact with walls correctly.

-You can't jump if you are moving against a wall (this is MC-142913)

-If you jump against a block you'll stand a little bit higher (0.1213 block) if you keep moving forwards.

-If you jump again, this time you'll stand 0.0429 blocks higher.

-If you fall from a high place and trying to move against a wall, the player can stand in the wall. The high you'll end depends of the high you were when you fell. For example, if you're standing 4 blocks high, you'll end 0.65373 block high. This is not proportional : if you're standing 5 blocks high, you'll end 0.15552 block high. If you're standing 150 blocks high, you'll end 1.91484 blocks high.

-You can literally walk on walls (and if you have blocks above your head it reduces your heigh while walking on walls)

-If you are in water, if there is slime blocks below it, and if you walk against the wall the player keeps moving strangely. In order to reproduce it, you need to be against the wall, press jump and move forwards at the same time. Once you're glitched you don't need to press jump anymore. You can reproduce it without slimeblocks but it is a little bit more tricky.

-2 mobs or players are stucked if they are in a 1x1 hole (probably because they are pushing each other against the wall)

See the screenshots and videos attached.

 

Linked issues

MC-142947 New Collision System 19w04a MC-143010 New collision code glitch: Walking along a block will keep you at the blocks elevation despite gravity (wall riding) MC-143073 Wall Spider effect MC-143078 Sliding down blocks when pressing against them if walking off of edge MC-143096 Falling Slowly while pressed against block MC-143100 19w04b jumping still broken, but differently MC-143109 Downstairs & Walls MC-143116 Floating down walls MC-143117 slow falling MC-143161 Sheep acting like they are climbing a ladder when going up a block. MC-143162 Slow Fall/Wall Fall Glitch MC-143164 Hugging the wall while walking off a wall makes you fall slowly MC-143221 You can slide on the walls as well as on the vines MC-143301 Slow falling when walking off a block beside wall MC-143344 Player acts like he has slow falling when sprinting against a wall and going down

Attachments

Comments

David abercrombie

Also you can not jump up on a block when standing against it

Les Vosla

Even walking up stairblocks is affected by this. No smoothly walking up a staircase. Movement "stutters". Also "Auto-jump" on or off does not have an effect on this behavior.

Nigel Todman

Can confirm, 19w04a on Linux Server, Win8.1 Client

Happens with or without armor/items in hand

Stef B

You can literally walk on walls.

It's not a bug, it's a feature!

Valicon

Confirmed for 19w04b, please reopen. This is only partially fixed, players and mobs still interact strangely with walls.

TheBoy358

Please reopen

TheBoy358

Please attach a small video later to see.

TheBoy358

Thanks.

Makzevu

Isn't that MC-44560?

Valicon

Doubletoad74

No, player isn't touching the ground and is still jumping. It has nothing to do with auto-jumping. Plus this is done with water source, not water edge. Plus this bug was introduced with 19w04a

Makzevu

This issue exists in 1.13 when the height of the water block's hitbox was increased: https://www.dropbox.com/s/q2ne1z5ps4carkz/Minecraft%202019.02.15%20-%2015.57.25.03.mp4?dl=0

The video doesn't make this clear, but there is a slab where the armor stand is bouncing.

TheBoy358

There are already a ticket talking about the "Interactions on walls with water" MC-50749

Makzevu

The original issue that occurred through the snapshots isn't fully fixed. The reason why the original issue existed is because when the new collision system was added, it enabled the momentum of any entity's movements to remain the same while colliding with any block. This allowed the walking on walls effect and the slow falling effect.

Later, the collision rule was changed one last time making entities not retain their momentum while colliding with blocks by walking straight into them, but didn't account for when entities walk into a corner: https://youtu.be/PZSUH7x9gYA. Fortunately, entities have to move and retain their momentum in order to trigger the original issue (meaning that there isn't much wrong here since entities can't travel while walking into a corner), but still is an incorrect wall interaction, 

Thommy Siverman

Seems like the only still valid issue in this ticket is the water bounce, which is tracked in MC-50749.

Please reply and clarify if that assumption is wrong.

Valicon

I think this is correct, whuch means that this issue is fixed

Valicon

migrated

Confirmed

Hitboxes

collision, entities

Minecraft 19w04a, Minecraft 19w04b, Minecraft 19w05a, Minecraft 19w06a, Minecraft 19w07a, ..., 19w35a, 19w36a, 1.15.2, 20w07a, 1.16

Minecraft 19w04b

Retrieved