Units ungarrisoned from a ship run back to the point they garrisoned

[sanderd17]

When you ungarrison units from a ship, they want to run back to their garrison point (which isn't always possible). This behaviour seems to only happen once per unit (so it doesn't happen the second time you garrison the same unit).

It also doesn't happen with the siege tower (which also is a moveable garrisonholder), so it's probably related to Ships moving towards the units themselves.

[mimo]

The problem seems to be with the formation: when units in formation are asked to garrison, the formation is not disbanded and the garrison position is the last position before garrisoning. Then when we ungarrison the units after having moved the ship, this last formation position is used by Formation.js in MoveMembersIntoFormation. But I must have missed something in this interpretation as otherwise, the problem would always appear while it seems to be random (and quite rare). A simple fix would be to disband the formation when garrisoning it.

[serveurix]

I've seen this bug happening with siege engines too, nut just ships.

[sanderd17]

I think we should remove the members from the formation instead of disabling the formation on garrison. When you queue garrison orders (i.e. to split a group between two towers), disbanding the formation will lead to not executing the second command. While only removing some members will not.

[sanderd17]

In 15181:

Remove members from a formation when they garrison. Fixes #2545