Dwarf Fortress Bug Tracker - Dwarf Fortress
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0008308Dwarf FortressDwarf Mode -- Buildings, Generalpublic2014-09-17 05:402016-07-31 06:42
0008308: Strange interactions between trees and bridges
Bridges can be built in trees (supported by branches or trunks) without harming the tree. I found two issues, both presumably caused by strange interactions with tree parts:
1. tiles under a bridge only count as "inside" if those bridge tiles were constructed over "open space". Bridge tiles on branches or twigs have "outside" tiles underneath.
2. bridge tiles constructed on twigs cannot be crossed by dwarfs.

I suspect bridges don't assert their presence when intersecting with trees (which might be why they can be built there in the first place).
Access the higher levels of trees via ramps/stairs. Build bridges there. Observe inside/outside patterns on the levels below, check access/movement on the bridges.
related to 0007872new  Trees growing through bridges 
Issue History
2014-09-17 05:40Larix2New Issue
2014-09-17 06:50KirkegaardNote Added: 0030228
2014-09-17 06:51KirkegaardNote Edited: 0030228bug_revision_view_page.php?bugnote_id=0030228#r11797
2014-09-17 08:03Larix2Note Added: 0030230
2014-09-17 08:03Larix2Tag Attached: trees
2014-09-26 08:49Larix2Note Added: 0030383
2014-09-26 08:49Larix2Note Edited: 0030383bug_revision_view_page.php?bugnote_id=0030383#r11867
2016-07-31 06:42LociRelationship addedrelated to 0007872

2014-09-17 06:50   
(edited on: 2014-09-17 06:51)
Do you have a save?
If yes, please upload it here: http://dffd.wimbli.com/ [^]

2014-09-17 08:03   
http://dffd.wimbli.com/file.php?id=9721 [^]
2014-09-26 08:49   
Looking through other reported bugs, this one might be related to Issue 0007872 - bridges not counting as solid constructions may be why trees can grow through them.