Mantis Bug Tracker

View Issue Details Jump to Notes ] Issue History ] Print ]
IDProjectCategoryView StatusDate SubmittedLast Update
0007121Dwarf FortressVegetationpublic2014-07-12 02:082021-07-16 17:42
Assigned ToLoci 
PlatformOSOS Version
Product Version0.40.02 
Target VersionFixed in Version 
Summary0007121: Cutting down mushroom trees leaves floating ramps of indeterminate material
DescriptionCutting down giant cave mushrooms (tower-cap, goblin-cap, black-cap, etc.) frequently leaves behind a ring of floating ramps. This happens on every 'cap that has ramps on it (simply labeled tower-cap cap on loo(k) view.)
Steps To ReproduceCut down any giant shroom that has ramps on the cap in dwarf mode.

May be limited to shrooms that have their caps against cavern ceiling.
Additional InformationThe ramps are single-tile - they do not have corresponding ramp either above or below.
TagsNo tags attached.
Attached Files

- Relationships
related to 0001573confirmedFootkerchief Underground trees leave behind soil floors when cut down 
related to 0001547confirmedFootkerchief Cave-ins can leave hanging down ramps in air 
has duplicate 0008084resolvedlethosor Subterranean trees leave unusable ramps behind. 

-  Notes
Talvieno (reporter)
2014-07-14 07:19
edited on: 2014-07-14 07:20

Can confirm this. It's not limited to those that have caps against the cavern ceiling - I cut some down at the bottom of a deep pit and had the same thing occur.

MrC (reporter)
2014-08-13 15:31

Also confirming this glitch.
Talvieno (reporter)
2014-08-18 10:05
edited on: 2014-08-19 21:14

Can confirm that this still happens in 40.09.

Edit: Here's an interesting addition: if a tree grows back in its place, like a spore tree, fungiwood, or blood thorn, the ramps change color to match the color of the new tree, but the tiles aren't updated.

ptb_ptb (reporter)
2014-11-22 07:17
edited on: 2014-11-22 07:18

There is similar behavior where unusable down slopes and vermin colonies are left floating in the air after large cave-ins.

Save file (before cave in): [^]

See 0008573 for how to cave in the left hand side of the map.

ptb_ptb (reporter)
2014-11-22 07:21

I think this is related to, or duplicate of
anewaname (reporter)
2017-04-19 16:22
edited on: 2017-04-19 16:22

I have observations and speculation to add to this. In the dffd save below, there is a dwarf busy chopping a tree, where the tree's ramp was part of the route up to the fortress. A few seconds after the tree fell, I did 'b''C 'W' and as shown in this image ( [^]), the distance to the materials is a negative number. Whether the wall was placed or not, FPS dropped from the cap of 50 to 4, for ten or twenty minutes, and there was much eat/drink job cancel spam, then the FPS returned to 50.

In comparison, if you 'd' 'x' the tree and 'd' 'z' that staircase, there is no FPS hit or job cancellation spam. My speculation is that these half-ramps (and the half-ramps in issue 0001547, possibly from upon-embark cave-ins) might effect pathing of fortress invaders (FBs, booze-thieves, etc) and cause some of those sudden FPS drops that players run into.

The game is 43.05 x64 from linux with MayDay tileset and no mods or dfhack used. [^]

Loci (manager)
2017-04-23 12:00

@anewaname: Thank you for the save. The negative distance bug is a continuation of 0004372, which I have split out to 0010208.
Dwarfu (manager)
2017-11-29 20:28

These mushrooms don't have ramps as of 44.01.
Loci (manager)
2017-11-30 14:15

Yes they do, and they're still buggy as described above. Here's a before/after screenshot in v0.44.02: [^]
Dwarfu (manager)
2017-11-30 15:01

Was that generated in 44.02? My game is unmodified and I’m looking at those mushrooms and they don’t have ramps and they cut down cleanly.
mrmagolor (reporter)
2017-11-30 17:47

I had this happen to me in 0.44.01.
Loci (manager)
2017-11-30 22:17


Yes. How tall are your caverns? Mushroom trees seem to require at least 3 z-levels to produce ramps, and 4 z-levels to produce the problematic down-ramp tiles.
Dwarfu (manager)
2017-12-01 07:33

That’s exactly what it is. After looking over the caverns to try and narrow it down (because I certainly had the bug in previous versions), I see that although the caverns meander through 4-5 z-levels, at no point within them is there more than 2 z-levels available growth space.

I didn’t see anything in this report related to their size, but at least we’ve recorded the distinction now.
Bumber (reporter)
2021-07-16 17:42
edited on: 2021-07-16 17:43

I was reverse engineering tree-cutting code and think I found the cause of this. When removing the tree's tiles, it iterates from the top down. If there's an up ramp below the tile to be removed, it puts a down ramp in the tile (replacing the tree's down ramp with another down ramp.) It then proceeds downwards and removes the up ramp tile (because it's part of the tree,) and so on until it reaches the ground.

The simple fix is to check if the up ramp below is part of the tree, and put empty space instead of a down ramp if it is.

- Issue History
Date Modified Username Field Change
2014-07-12 02:08 Kumquat New Issue
2014-07-14 07:19 Talvieno Note Added: 0026317
2014-07-14 07:20 Talvieno Note Edited: 0026317 View Revisions
2014-08-13 15:31 MrC Note Added: 0028993
2014-08-13 15:35 Footkerchief Relationship added related to 0001573
2014-08-13 15:35 Footkerchief Assigned To => Footkerchief
2014-08-13 15:35 Footkerchief Status new => confirmed
2014-08-18 10:05 Talvieno Note Added: 0029233
2014-08-19 21:14 Talvieno Note Edited: 0029233 View Revisions
2014-08-20 04:55 lethosor Relationship added has duplicate 0008084
2014-11-22 07:17 ptb_ptb Note Added: 0031116
2014-11-22 07:18 ptb_ptb Note Edited: 0031116 View Revisions
2014-11-22 07:21 ptb_ptb Note Added: 0031118
2014-11-24 07:04 Footkerchief Relationship added related to 0001547
2017-04-19 16:22 anewaname Note Added: 0036433
2017-04-19 16:22 anewaname Note Edited: 0036433 View Revisions
2017-04-23 12:00 Loci Note Added: 0036447
2017-06-08 18:32 Huntthetroll Issue Monitored: Huntthetroll
2017-11-29 20:28 Dwarfu Note Added: 0037125
2017-11-29 20:28 Dwarfu Status confirmed => resolved
2017-11-29 20:28 Dwarfu Fixed in Version => 0.44.01
2017-11-29 20:28 Dwarfu Resolution open => fixed
2017-11-29 20:28 Dwarfu Assigned To Footkerchief => Toady One
2017-11-30 14:15 Loci Note Added: 0037145
2017-11-30 14:15 Loci Assigned To Toady One => Loci
2017-11-30 14:15 Loci Status resolved => confirmed
2017-11-30 14:15 Loci Resolution fixed => open
2017-11-30 14:15 Loci Fixed in Version 0.44.01 =>
2017-11-30 14:15 Loci Description Updated View Revisions
2017-11-30 14:15 Loci Steps to Reproduce Updated View Revisions
2017-11-30 14:15 Loci Additional Information Updated View Revisions
2017-11-30 15:01 Dwarfu Note Added: 0037147
2017-11-30 15:02 Dwarfu Status confirmed => needs feedback
2017-11-30 17:47 mrmagolor Note Added: 0037152
2017-11-30 22:17 Loci Note Added: 0037155
2017-11-30 22:17 Loci Status needs feedback => confirmed
2017-12-01 07:33 Dwarfu Note Added: 0037161
2021-07-16 17:42 Bumber Note Added: 0041099
2021-07-16 17:43 Bumber Note Edited: 0041099 View Revisions

Copyright © 2000 - 2010 MantisBT Group
Powered by Mantis Bugtracker