0004561: Newly built wall freezes caravan, even after it's removed

Dwarf Fortress Bug Tracker - Dwarf Fortress

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Category

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Date Submitted

Last Update

0004561

Dwarf Fortress

Dwarf Mode -- Trade

public

2011-04-23 02:15

2014-01-25 08:07

Reporter

GreenSpinach

Assigned To

Priority

high

Severity

major

Reproducibility

have not tried

Status

new

Resolution

open

Platform

OS Version

Product Version

0.31.18

Target Version

Fixed in Version

Summary

0004561: Newly built wall freezes caravan, even after it's removed

Description

I was dealing with a goblin ambush, and ordered the construction of a wall to block off my secondary entrance. Before it was built, the dwarven caravan came, and began going in through that entrance. When the wall was finished, 1 merchant, 1 caravan guard and 1 horse were still outside. They refused to re-path through the primary entrance (an entrance that was wide enough to allow the entry of wagons, if only they existed. When is Toady going to fix the "no wagons" bug?), and just sat there. They remained there even after I opened the wall back up, making it possible for them to continue on their original path. I then began setting up for two cave-ins, one which was to stun the horse with cave-in dust, and one to kill the horse with a falling floor (but I incorrectly positioned the second floor). I also built a floor over the merchant and guard, and that was to give a dwarf a place to standing when deconstructing the corner wall.
It was at this point that I saved the game and uploaded the save.
Hitting the horse with cave-in dust didn't work. Killing the horse with a falling floor caused the caravan to immediately leave and take all their goods with them (except what the dead horse had, of course), because they had not unloaded anything.
Channeling the horse's square to make it fall unfreezes the caravan. I tried this as an afterthought, after I had already pretty much decided to rage quit Dwarf Fortress. After screaming obscenities and yelling that I would never play Dwarf Fortress again, I loaded this save to see if there were any really unusual conditions in the situation, and I got the idea to make the horse fall. I was surprised that it worked.
But then something else weird happened. After the horse fell I was able to trade immediately, but was of course only able to buy things from the first 2 horses. So I bought all their stuff and waited for the third horse to arrive. (It took a long time, because it stayed in "prone" mode the whole way.) When it finally got there, it never unloaded anything. So it looks like I can't buy the goods on the third horse.
The first save is http://dffd.wimbli.com/file.php?id=4254 [^]
The second save is http://dffd.wimbli.com/file.php?id=4255 [^]

Steps To Reproduce

1. Build a fortress with 2 long, narrow entryways. Where each entryway connects to the room containing your Trade Depot, include some means of blocking the way. A drawbridge is probably best.
2. Channel every other square in the entryways, to insure that merchants are constantly going up and down ramps as they walk through the entryways. I have a hunch that it is important to have the last merchant and his horse on different Z-levels when you block off the entryway.
3. When the caravan comes, wait for at least 1 merchant and his horse to go through the doorway. When at least one merchant has gone through (along with his horse) and at least 1 merchant and his horse are still in the bumpy entryway, close the door (or drawbridge, or floodgate, or wall, or whatever).
4. At this point, the merchant should refuse to re-path, and just stop in his tracks, and stay stopped even if you open the door/bridge/whatever. If the bug doesn't happen, try looking at my save to see if there's some factor I overlooked.
5. Optionally, try out the workaround for this bug, which involves digging or channeling to make the merchant or his horse (whichever is higher up) fall down a Z-level so that they are both on the same Z-level.

Additional Information