Dwarf Fortress Bug Tracker - Dwarf Fortress
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0007130Dwarf FortressPathfindingpublic2014-07-12 07:582018-01-19 16:25
Toady One 
0007130: you can climb diagonally through walls if there are twigs above the wall
when the terrain is as follows (side view):

where # is wall and " is twigs or leaves from a tree and x is empty, it is possible to climb between the twigs and the x.
build walls as shown next to an existing tree (apparently trees will not grow on their own so close to the walls).
you can now climb through the wall where the tree is.
I found and tested this bug in arena mode, where I created the walls by placing water and magma.

PS: maybe a new category for climbing would be appropriate.
Climbing, Intentional/Expected?, trees
related to 0007521resolved Toady One burning leaves over walls won't make floor appear (at least in arena mode) 
related to 0008383resolved Toady One Flying/swimming/climbing creatures can move vertically through diagonal gaps containing down-stairways 
Issue History
2014-07-12 07:58JoeJoeNew Issue
2014-07-12 07:59JoeJoeTag Attached: Climbing
2014-07-12 07:59JoeJoeTag Attached: trees
2014-07-12 08:27FootkerchiefTag Attached: Intentional/Expected?
2014-07-12 16:23shinzirilNote Added: 0026045
2014-07-12 20:46JoeJoeNote Added: 0026072
2014-07-20 14:33JoeJoeNote Added: 0027064
2014-07-20 20:50lethosorDescription Updatedbug_revision_view_page.php?rev_id=10125#r10125
2014-07-20 20:51lethosorNote Edited: 0026072bug_revision_view_page.php?bugnote_id=0026072#r10127
2014-07-24 16:13LociNote Added: 0027456
2014-07-27 12:48FootkerchiefRelationship addedrelated to 0002820
2014-08-18 13:35FootkerchiefRelationship addedrelated to 0007521
2014-10-01 18:15FootkerchiefRelationship addedrelated to 0008383
2014-10-01 18:15FootkerchiefRelationship deletedrelated to 0002820
2018-01-19 16:25Toady OneStatusnew => resolved
2018-01-19 16:25Toady OneFixed in Version => Next Version
2018-01-19 16:25Toady OneResolutionopen => fixed
2018-01-19 16:25Toady OneAssigned To => Toady One

2014-07-12 16:23   
I don't think this is climbing-specific, I'm pretty sure flying creatures were able to do this in previous versions. It might even be intentional on Toady's part; if you have walls diagonally adjacent on the horizontal plane, you can walk between them the same way.
2014-07-12 20:46   
(edited on: 2014-07-20 20:51)
did some further testing, apparently this is an extended result of issue 0007127, because no floor is placed on the twig tile when the wall is created, which might be intended.

Also, a creature that falls onto the open space tile after removing the tree/twigs will be "Flying" and unable to do anything until it dies of dehydration.

2014-07-20 14:33   
behaviour is the same for version 0.40.04
2014-07-24 16:13   
In v0.34, flying creatures could move vertically-diagonal through two walls only when the there was a stairway above the lower wall (side view):


Non-flying creatures cannot make the same movement (using a ramp in the lower tile), nor can liquid in the stairway diagonally descend.

Presumably the stairway is acting in a similar manner to override the floor implied by the wall below.