Dwarf Fortress Bug Tracker - Dwarf Fortress
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0000891Dwarf FortressPathfindingpublic2010-04-09 12:462014-01-27 13:19
normalmajorhave not tried
resolvedunable to reproduce 
0000891: New HFS pathing troubles; ends up in a pathing "freeze"
This post will contain necessary spoilers.

I recently breached "hell" and had a whole slew of demons fly up to kill me and my fort. That was cool and all...until I had only two dwarves left. Every demon decided to path towards a sleeping dwarf. They were forced down a single tile wide hallway, and it seemed that all but 2 of the demons ended up "stuck" in the hallway, as if they were all waiting for the other to move out of the way.

The dwarf eventually died, but the demons remaiend stuck in the hallway despite another dwarf living in a different part of the fort. The demons are still stuck.

After observing them it appears that they're stuck in some sort of "making room" loop. After room is made (you can see a demon dart into a doorway for a split second), it seems that same demon then moves into a spot that is freed. As such they're stuck forever.

Saving and reloading did NOT fix this problem
There is absolutely nothing preventing their pathing to the last dwarf in the fort. Indeed, several dead dwarves are on the same level as him.

I suspect it has to do with their flier tag?

Save - http://www.megaupload.com/?d=U0ZZXYHW [^]
HFS, pathfinding
parent of 0000628resolved Dwarfu Crash while under attack by HFS 
related to 0001340new  Walling off HFS kills FPS 
Issue History
2010-04-09 12:46SirPenguinNew Issue
2010-04-12 21:27SirPenguinNote Added: 0003200
2010-04-12 21:27SirPenguinTag Attached: pathfinding
2010-04-12 21:27SirPenguinTag Attached: HFS
2010-04-12 21:35SirPenguinIssue Monitored: SirPenguin
2010-04-14 12:42lord_chaos22000Issue Monitored: lord_chaos22000
2010-04-19 13:38FootkerchiefNote Added: 0004263
2010-04-19 13:38FootkerchiefNote Edited: 0004263bug_revision_view_page.php?bugnote_id=0004263#r1425
2010-04-19 13:40FootkerchiefRelationship addedrelated to 0001340
2011-03-13 06:28DwarfuRelationship addedparent of 0000628
2014-01-27 13:19FootkerchiefNote Added: 0024405
2014-01-27 13:19FootkerchiefStatusnew => resolved
2014-01-27 13:19FootkerchiefResolutionopen => unable to reproduce
2014-01-27 13:19FootkerchiefAssigned To => Footkerchief

2010-04-12 21:27   
Problem still occurs in .03, which is a shame. I was hoping to have a proper end to that fort :(
2010-04-19 13:38   
This may be related to an old bug:

# 000812 □ [pathfinding] (http://www.bay12games.com/forum/index.php?topic=6793.0 [^]) dwarves can get stuck in a looping pattern trying to avoid each other

2014-01-27 13:19   
Save is no longer available. If you have a save that demonstrates this problem in the latest version, please upload it to http://dffd.wimbli.com/ [^] and reopen this report (or PM me on the forums).