MasterDan found this bug, but he can't post on this forum for some reason. He should get credit for squashing this bug.
Descriptive Problem Summary:
If you use Move(vector) or Walk(vector) for a projectile (or presumably any movable atom), when you join a server using this method, the object will randomly change directions as it moves, seemingly as it enters a new turf. The direction corrects itself shortly after but end up looking terrible.

Note that if you run the same source file in dreamseeker in single player mode, the bug doesnt occur.


Numbered Steps to Reproduce Problem:
Ensure game is hosted in dreamdaemon, and you join the server.
Create an object/mob.
Tell it to Walk(vector) or Move(vector) for more than 1 tile.
Observe it snapping directions as it enters new tile, and then snaps back to the correct direction.

Code Snippet (if applicable) to Reproduce Problem:
https://discord.com/channels/725444629172060262/ 725458744711839873/1351345882133696553

Expected Results:
Not to spastically change directions as it moves
Actual Results:
Spastically changes directions as it moves.
Does the problem occur:
Every time? Or how often? Every time
In other games? Yes. Its an issue in SOA currently, and experienced by Otis who is working on other projects.
In other user accounts? Yes, verified by at least three different people on different machines.
On other computers? Yes.

When does the problem NOT occur?
If you run the game in dreamseeker without hosting.
Did the problem NOT occur in any earlier versions? If so, what was the last version that worked? (Visit http://www.byond.com/download/build to download old versions for testing.) Im not sure, since movement/walk has supported vectors its been an issue but I didnt know what caused it until recently.

Workarounds:
Dont use vectors in Move/Walk, or dont host the game online.