AI Unit Position Not Updating with getPosition() (Late Activation Issue?)

[Crossmann]

Context: What I'm Trying to Achieve

I'm scripting a mission in DCS where a player-controlled unit (BLUE_SEAD_1-1) has an AI escort (AI_BLUE_ESC_2-1). The escort is set to Late Activation and only spawns if no human player takes control of it.

I have written a Lua script that allows the player to use an F10 menu option ("Colt Report Position") to check:

• Their own current position (X, Y, Z)
• The escort's current position (X, Y, Z)
• The distance between them
• The bearing of the escort relative to the player (in degrees & clock position)

The function retrieves the units dynamically and calls getPosition() on both to get the updated coordinates.

---

The Issue: AI Escort's Position Doesn't Update

While the player's position updates correctly every time they call the function, the escort's position remains frozen at its initial mission editor coordinates (even though the escort is moving in-game).

This means:

• The getPosition() function returns the correct values for the player, but
• The escort's position always remains the same, even though the AI aircraft has moved.

---

Debugging Attempts

1. Checked if the unit is being retrieved correctly
   Unit.getByName("AI_BLUE_ESC_2-1") returns a valid unit, meaning it exists.
    Unit.getByName("AI_BLUE_ESC_2") also retrieves the unit correctly

2. Confirmed that the function executes only after the AI escort is spawned
   The menu function is only available after the escort is activated.

3. Tried multiple retrieval methods for escort position

   • EscortUnit:getPosition() No update; position remains static.
   • EscortUnit:getPoint() Same issue.
   • Object.getByName("AI_BLUE_ESC_2-1") No difference.
   • coalition.getGroups() to dynamically find the group Still no position updates.

4. Checked the DCS logs
   The script logs confirm that the escort's position never changes after the first retrieval.
   The player’s position updates dynamically as expected.
    

   local function ReportEscortPosition()

       env.info("ReportEscortPosition called!")

    

       -- Retrieve Player Unit

       local LeadUnit = Unit.getByName("BLUE_SEAD_1-1")

       if not LeadUnit then

           env.info("ERROR: LeadUnit (BLUE_SEAD_1-1) not found.")

           return

       end

    

       -- Retrieve AI Escort Unit

       local EscortGroup = Unit.getByName("AI_BLUE_ESC_2-1")

       if not EscortUnit then

           env.info("ERROR: EscortUnit not found.")

           return

       end

    

       -- Get positions

       local LeadPos = LeadUnit:getPosition()

       local EscortPos = EscortUnit:getPosition()

    

       if not LeadPos or not EscortPos then

           env.info("ERROR: Could not retrieve positions.")

           return

       end

    

       -- Extract coordinates

       local PlyrPos = LeadPos.p

       local EscPos = EscortPos.p

    

       -- Calculate distance

       local dX = EscPos.x - PlyrPos.x

       local dZ = EscPos.z - PlyrPos.z

       local distance = math.sqrt(dX^2 + dZ^2) / 1000

    

       -- Calculate bearing (this is not correct as no check for the quadrants is still implemented)

       local bearing = math.deg(math.atan2(dX, dZ))

       if bearing < 0 then

           bearing = bearing + 360

       end

    

       -- Convert to clock position (1-12)

       local clockPosition = math.floor(((bearing + 15) % 360) / 30) + 1

    

       -- Debug logs

       env.info(string.format("Player Position: X=%.1f, Y=%.1f, Z=%.1f", PlyrPos.x, PlyrPos.y, PlyrPos.z))

       env.info(string.format("Escort Position: X=%.1f, Y=%.1f, Z=%.1f", EscPos.x, EscPos.y, EscPos.z))

       env.info(string.format("Escort is %.1f km away, Bearing: %.1f°, Clock: %d o’clock", distance, bearing, clockPosition))

   end

   Questions for the Community

5. Why is getPosition() not updating for the AI escort, even though the unit is moving in-game?
6. Does Late Activation affect how getPosition() works? If so, how can I force it to return updated coordinates?
7. Is there a workaround to get the escort’s real-time position dynamically?
8. Is this a known issue in DCS scripting, or am I missing something?

   Any insights or fixes would be greatly appreciated!

   Let me know if you need additional logs or a test mission file.

   Thanks in advance!

Edited March 1 by Crossmann
wrote group instaed of unit in a place

[Mistermann]

I just spent far too much time figuring out how to do this last week.  I use it for late activated units and it works great. I use this command, not getPosition.

local _targetCoord = Unit.getByName(_unitName):getPoint() <-- _unitName would be your "AI_BLUE_ESC_2-1"

Try going that route.  

Edited March 1 by Mistermann

[cfrag]

17 hours ago, Crossmann said:

Why is getPosition() not updating for the AI escort,

Check your variable names, especially escortGROUP vs escortUNIT. Methinks EscortUnit isn't defined.

 

[Crossmann]

Follow-up & Apology - Issue Resolved

Hey everyone,

I just wanted to follow up on my previous post regarding the AI escort's position not updating and apologize for any confusion or unnecessary troubleshooting effort I may have caused.

After further investigation, I discovered that the issue was not actually related to getPosition() or the Late Activation of the AI escort itself. Instead, the root cause was a mission design choice in another part of my script, where I had implemented logic to dynamically spawn AI replacements for any client slots that were not occupied by human players. This resulted in the escort AI being spawned through a separate mechanism, which unintentionally interfered with how the unit was being referenced and tracked.

What Was Happening

• The getPosition() function was working correctly.
• However, the unit reference I was retrieving was still pointing to the original, pre-spawned unit from the Mission Editor, not the dynamically spawned AI escort.
• Because of this, even though the AI escort was moving in-game, my script was still looking at the old, inactive unit and returning static coordinates.

Solution

Once I adjusted my mission logic so that the AI escort was properly referenced after it was spawned, everything started working as expected. Now, I retrieve the correct instance of the spawned AI escort, and its position updates dynamically every time the player requests a position report.

I sincerely appreciate the time and effort that some of you may have spent trying to help troubleshoot this. Thank you all for your patience and support! Hopefully, this serves as a reminder to always double-check how units are being spawned and referenced dynamically in DCS scripting.

Thanks again!

[cfrag]

13 hours ago, Crossmann said:

the root cause was a mission design choice in another part of my script

It's good that you were able to resolve the issue.

Please be advised that your script still contains at least one show-stopping bug:

    local EscortGroup = Unit.getByName("AI_BLUE_ESC_2-1")
    if not EscortUnit then
        env.info("ERROR: EscortUnit not found.")
        return
    end

Your script should not progress past that point, and always end with the message "EscortUnit not found".