Dwarf Fortress Bug Tracker - Dwarf Fortress
View Issue Details
0006483Dwarf FortressDwarf Mode -- Jobs, Militarypublic2014-05-12 10:572014-10-05 18:34
Toady One 
normalminorhave not tried
0006483: Siege engines don't properly respect operator skill level
When a dwarf fires a siege engine, it aims at a location 60 tiles away from the siege engine (in the appropriate direction) and up to 10 tiles to each side, and if the dwarf passes a Siege Operator skill roll (1d15 <= skill_level) then the sideways drift is eliminated. If the projectile is a stone (being fired from a catapult), its trajectory is then calculated to see if any hostile units are in the way, and this is used to determine the stone's arc height (so it will land on the units instead of flying past them), while a ballista arrow will simply fly as far as it can.

At least that's how it looks like it's supposed to work. In reality, the skill roll's result is effectively ignored - the "more accurate" coordinates are only stored in temporary variables (which get used for the catapult stone height calculation) but never atually get written back into the projectile itself. As a result, a Legendary catapult operator will always miss a stationary target if it is standing off to either side.
This bug dates back to version 0.23 and likely all the way back to the original implementation of siege engines.
Issue History
2014-05-12 10:57QuietustNew Issue
2014-05-12 12:03QuietustNote Added: 0024755
2014-05-12 12:05QuietustNote Edited: 0024755bug_revision_view_page.php?bugnote_id=0024755#r9256
2014-05-12 12:06QuietustNote Edited: 0024755bug_revision_view_page.php?bugnote_id=0024755#r9257
2014-07-31 09:27NevenrialIssue Monitored: Nevenrial
2014-07-31 09:30TalvienoNote Added: 0028039
2014-07-31 09:40Dame de la LicorneIssue Monitored: Dame de la Licorne
2014-07-31 10:33TalvienoIssue Monitored: Talvieno
2014-07-31 10:334maskwolfIssue Monitored: 4maskwolf
2014-07-31 11:47dree12Issue Monitored: dree12
2014-09-13 06:41NevenrialTag Attached: siege
2014-09-13 07:04FootkerchiefAssigned To => Footkerchief
2014-09-13 07:04FootkerchiefStatusnew => confirmed
2014-09-13 11:50Toady OneStatusconfirmed => resolved
2014-09-13 11:50Toady OneFixed in Version => Next Version
2014-09-13 11:50Toady OneResolutionopen => fixed
2014-09-13 11:50Toady OneAssigned ToFootkerchief => Toady One
2014-09-13 12:13Dame de la LicorneIssue End Monitor: Dame de la Licorne
2014-09-16 10:00NevenrialIssue End Monitor: Nevenrial
2014-09-25 21:284maskwolfIssue End Monitor: 4maskwolf
2014-10-05 18:34TalvienoIssue End Monitor: Talvieno

2014-05-12 12:03   
(edited on: 2014-05-12 12:06)
A minor correction - whether this bug is fixed or not, highly skilled catapult operators will still miss targets off to the side, but fixing the bug will make it more apparent why they are missing (namely, the stones would fly perfectly straight and past their targets, as opposed to flying to the side and going through their targets).

In either case, fixing the bug would make ballistas more useful, as it would allow them to be used properly in long corridors without worrying about hitting the walls.

2014-07-31 09:30   
If it was fixed I might actually start using them. This explains quite a bit... Quietust, I'm sure you get told this a lot, but you are awesome.