mojira.dev
MC-99442

Changing an Arrow's Motion using /data causes client-server-desync

When you update the Motion of a flying Arrow with /data, it does only update serverside.

To reproduce, you can use the following commands:

/summon arrow ~ ~2 ~ {NoGravity:1b}

/data merge entity @e[type=arrow,limit=1,sort=nearest] {Motion:[0d,0d,-0.5d]}

You should see, that the arrow ow "jumps" every so often to its new sever-side position but still facing the direction it was facing when it was summoned.

Linked issues

Comments

NeunEinser

Since in the recent 1.10 Snapshot there is NoGravity for all Entities, you can see the effect for an Arrow with NoGravity very clearly.
Just do:

/summon Arrow ~ ~-1 ~ {NoGravity:1b}
/entitydata @e[type=Arrow,c=1] {Motion:[0d,0d,-0.5d]}
Irbis

fixed somewhere between 1.14 and 20w06a

wobst.michael

1.15.2 also isn't affected by this.

Diego Cattaneo

This still happens in the latest version, 1.21.2 Pre-Release 5:
How I encountered it: changing an arrow's motion with the tick function as soon as I shot it. It will only update when the arrow lands. Not fixed.
Suspected solution: just update the client on the arrow's motion when it is changed by a command.

NeunEinser

(Unassigned)

Confirmed

(Unassigned)

Minecraft 1.9, Minecraft 1.9.1 Pre-Release 2, Minecraft 1.9.4, Minecraft 16w20a, Minecraft 1.10, ..., Minecraft 18w03b, Minecraft 1.13-pre3, Minecraft 1.13-pre6, Minecraft 1.13-pre7, Minecraft 1.13.1

1.15.2

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