Bug #28401

AI gets aware of friendly units which are in different groups if AI is watching in their direction dispite having its sight blocked by objects

Added by DrakeDarkstarr almost 4 years ago. Updated over 2 years ago.

Status:Assigned Start date:02/04/2012
Priority:Normal Due date:
Assignee:Dwarden % Done:


Category:AI Issues
Target version:-
Affected ArmA II version:1.62.95248 First affected build:
Reproduced by another DH user:Yes First affected ArmA II version:
I am using some Mods:No Single / Multi Player?:
I am using:OA only BIForumURL:
Reproducible for you:Yes NGUrl:
Related to content of DLC: WIKIurl:


I made some scripts involving firendly units that are in a different groups using nearTargets.
I noticed when the AI is looking in the direction where a friendly unit is, the friendly unit gets automatically revealed and the value of knowsAbout rises to the maximum (4) regardless of having objects which are blocking the AI's view.
In case of nearTargets, the 5th parameter (position accuracy) stays at the same value as long as the AI is looking in the same direction where the friendly unit is.

  1. Start attached mission in single player
  2. Order your teammate to look in direction of South by using 3-8-5
  3. Notice that within a couple of seconds the friendly units are known by the AI and the position accuracy in nearTargets array stays at a minimal value dispite of having the view blocked by the bulding
  4. Go behind to bulding to reveal the enemy and civilian unit
  5. Go back to your teammate
  6. Order your teammate to watch in direction of North by using 3-8-1
  7. Repeat step #2 and #6 to see how position accuracy reacts

Assumingly Level of Sight is not being calculated correctly for friendly units in different groups, meaning that not only obvious information are percieved, which can slightly change the game experience.

Level of Sight for AI involving friendly units is calculated as in case involving civilians and enemy units, so the AI won't percieve any information about the friendly units just by looking in their direction if the view is blocked by objects, i.e. like in case when the friendly unit is behind the AI.

If nearTargets is being executed for a player having an AI as teammate where the AI faces the direction where friendly units are, the value of position accuracy for the player is overidden by the AI (as if the player would have direct sight regarding the friendly units).
I'm using the latest beta, but this can be found in 1.60 as well in (much) earlier versions, but I can't tell exactly.

position_accuracy.Zargabad.7z - nearTarget test for friendly units (1.5 kB) DrakeDarkstarr, 02/04/2012 22:46

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Updated by kju almost 4 years ago

  • Category set to AI Issues
  • Affected ArmA II version set to 1.61 Beta
  • First affected build deleted (Please Specify...)

Interesting observation.

Yet it is more complicated than it appears I think:
  1. Units in the same group share the knowsAbout value
  2. No matter their distance to each other (all seems to have a perfect radio)
  3. This probably also relates to nearTarget info shared
  4. Friendly units share their position at mission start (according to Suma)

Now we don't know the details on the last one, like
how it affects knowsAbout and reveal or just some other internal info (sharing).

One can see that
  1. the player becomes aware of close friendly units - distant ones he does not or less likely
  2. for friendly AI the LOS check seems simplified - they can see each other through buildings

I am using the DevCon for debugging.

Updated by kju almost 4 years ago

  • Status changed from New to Assigned
  • Assignee set to Dwarden
  • Reproduced by another DH user changed from No to Yes

For some reason they see through buildings their own friends yes.

Updated by kju over 3 years ago

  • Affected ArmA II version changed from 1.61 Beta to 1.62.95248

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