Player Squad Group Join Protocol

Player Squad / Group Join Protocol

Source-verified 2026-06-21 against then-current master cf2a6d6a4; current origin/master is 0139a346, so recheck cited paths before current-head claims. Paths relative to Missions/[55-2hc]warfarev2_073v48co.chernarus/ unless noted. Arma 2 OA 1.64.

The squad system lets players move between groups mid-mission. All client-side logic lives in Client/Functions/Client_FNC_Groups.sqf. Server arbitration runs through Server/Functions/Server_HandleSpecial.sqf. Client-to-client notifications travel via Client/PVFunctions/HandleSpecial.sqf.

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Constants

All constants are defined in Common/Init/Init_CommonConstants.sqf. WFBE_C_AI_TEAMS_ENABLED is exposed as a lobby parameter (overrideable via Rsc/Parameters.hpp); the three squad constants (WFBE_C_PLAYERS_SQUADS_MAX_PLAYERS, WFBE_C_PLAYERS_SQUADS_REQUEST_TIMEOUT, WFBE_C_PLAYERS_SQUADS_REQUEST_DELAY) are hard-coded direct assignments and cannot be changed via mission parameters.

Constant	Default	Description	Source
WFBE_C_PLAYERS_SQUADS_MAX_PLAYERS	4	Maximum player count per squad (player leader included).	Init_CommonConstants.sqf:281
WFBE_C_PLAYERS_SQUADS_REQUEST_TIMEOUT	100	Seconds before an unanswered incoming request auto-expires from WFBE_Client_PendingRequests.	Init_CommonConstants.sqf:282
WFBE_C_PLAYERS_SQUADS_REQUEST_DELAY	120	Per-client cooldown (seconds) between successive join attempts.	Init_CommonConstants.sqf:283
WFBE_C_AI_TEAMS_ENABLED	1 (fallback default)	Enables joining AI-led groups. Parameter default is 0 (disabled). Fallback isNil guard sets 1.	Init_CommonConstants.sqf:98, Rsc/Parameters.hpp:81

The parameter UI default for WFBE_C_AI_TEAMS_ENABLED is 0 (Disabled); the isNil fallback in Init_CommonConstants.sqf:98 applies only when the parameter is absent entirely.

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Client-Side State Variables

Initialised in Client/Init/Init_Client.sqf:286-292 on every client connect/JIP.

Variable	Type	Purpose
WFBE_Client_Team	Group	The player's original spawn group (clientTeam); join-back target.
WFBE_Client_LastGroupJoinRequest	Number	Mission time of last join attempt. Starts at -5000 so the first attempt is always allowed.
WFBE_Client_PendingRequests	Array of [uid, name]	Incoming join requests visible in the Groups Menu. Leader's machine only.
WFBE_Client_PendingRequests_Accepted	Array of UIDs	UIDs accepted within the last 6 seconds; prevents duplicate ChangeUnitGroup calls on lag.

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Three Join Paths

WFBE_CL_FNC_UI_Groups_Join (Client_FNC_Groups.sqf:102) is called when the player selects a group in the Groups Menu. It enforces the cooldown and player-cap before branching on group type.

Path 1 — Re-join Original Team

Condition: the selected group == WFBE_Client_Team (Client_FNC_Groups.sqf:115).

The client calls WFBE_CO_FNC_ChangeUnitGroup locally (Client_FNC_Groups.sqf:116) — no server round-trip. The player is set as squad leader of the returned group (Client_FNC_Groups.sqf:117). Note: the source uses _unit (uninitialized at this scope, resolving to nil/objNull in A2) rather than player; this is a known latent source issue — in practice the selectLeader call may silently no-op.

Path 2 — Join Player-Led Group

Condition: isPlayer leader _group is true and alive leader _group (Client_FNC_Groups.sqf:125).

1. Client sends ["RequestSpecial", ["group-query", _group, player, WFBE_Client_SideJoined]] to the server (Client_FNC_Groups.sqf:126).
2. Server (Server_HandleSpecial.sqf:13-27) forwards ["group-join-request", _player] to the group leader via HandleSpecial.
3. Leader's client receives WFBE_CL_FNC_Groups_ReceiveRequest (HandleSpecial.sqf:23) — adds [uid, name] to WFBE_Client_PendingRequests and spawns the timeout watcher.
4. Leader acts via the Groups Menu (Accept or Deny).
   • Accept (WFBE_CL_FNC_UI_Groups_RequestAccept, Client_FNC_Groups.sqf:167-211): checks the player cap again against WFBE_Client_PendingRequests_Accepted + current players <= WFBE_C_PLAYERS_SQUADS_MAX_PLAYERS; adds the UID to WFBE_Client_PendingRequests_Accepted for 6 seconds (Client_FNC_Groups.sqf:191) first (lag-dedup guard), then calls WFBE_CO_FNC_ChangeUnitGroup on the joining player (Client_FNC_Groups.sqf:203), then sends ["group-join-accept", group player] to the requester.
   • Deny (WFBE_CL_FNC_UI_Groups_RequestDeny, Client_FNC_Groups.sqf:215-246): removes the request from WFBE_Client_PendingRequests and sends ["group-join-deny", group player] to the requester.
5. Requester receives accept/deny via HandleSpecial.sqf:20-21, which calls WFBE_CL_FNC_Groups_JoinAccepted or WFBE_CL_FNC_Groups_JoinDenied — both show a hint and, on accept, flush WFBE_Client_PendingRequests (Client_FNC_Groups.sqf:11).

Path 3 — Join AI-Led Group

Condition: isPlayer leader _group is false (Client_FNC_Groups.sqf:128-136).

Gated on WFBE_C_AI_TEAMS_ENABLED > 0. If the gate passes, the client sends the same "group-query" packet to the server. The server (Server_HandleSpecial.sqf:29-38) checks isNil {_group getVariable "wfbe_uid"} to confirm the group is genuinely AI-controlled (not a player group whose leader just died), then calls WFBE_CO_FNC_ChangeUnitGroup server-side and sends "group-join-accept" directly to the requester.

If AI Teams are disabled the client shows a warning hint and resets WFBE_Client_LastGroupJoinRequest = -5000 to waive the cooldown (Client_FNC_Groups.sqf:135) — the player can retry immediately.

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Gate Checks (join attempt entry, Client_FNC_Groups.sqf:110-151)

Evaluated in order; checks are nested; each failure short-circuits via its else branch and shows a hint, so only the first failing condition fires:

#	Check	Failure hint
1	group player != _group	"You are already in this squad."
2	_players < WFBE_C_PLAYERS_SQUADS_MAX_PLAYERS	"The player limit on this group has been reached (<N>)."
3	time - WFBE_Client_LastGroupJoinRequest > WFBE_C_PLAYERS_SQUADS_REQUEST_DELAY	"You cannot change groups that often, please wait <N> seconds."
4	alive leader _group	"The group you've attempted to join has no leader or the leader is dead."

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Kick Flow

Any player who is the group leader can kick a squad member. WFBE_CL_FNC_UI_Groups_Kick (Client_FNC_Groups.sqf:155-164) fires when the leader selects a member in list 508003 and clicks Kick.

1. Verifies isPlayer _selected && group _selected == group player (Client_FNC_Groups.sqf:159).
2. Removes the row from the UI list with lnbDeleteRow [508003, _ui_lnb_sel] (Client_FNC_Groups.sqf:160).
3. Sends [uid, "HandleSpecial", ["group-kick", group player]] to the target client (Client_FNC_Groups.sqf:161).
4. Target client receives WFBE_CL_FNC_Groups_KickedOff (HandleSpecial.sqf:22), which:
   • Calls [player, WFBE_Client_Team, WFBE_Client_SideJoined] Call WFBE_CO_FNC_ChangeUnitGroup (Client_FNC_Groups.sqf:27) — returns the player to their original team.
   • Calls WFBE_Client_Team selectLeader player if the player is not already the leader (Client_FNC_Groups.sqf:28).
   • Shows a hint: "You were kicked from the group <name>, you have been transferred back to your Original group."

The kicked player is routed back to WFBE_Client_Team — not to a freshly-created group.

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WFBE_CO_FNC_ChangeUnitGroup (Common)

Common/Functions/Common_ChangeUnitGroup.sqf. Called by all three join paths and the kick flow.

Signature: [_unit, _group, _side] Call WFBE_CO_FNC_ChangeUnitGroup

If _unit is the last live member of its current group, a temporary filler AI of class WFBE_<SIDE>SOLDIER is created in that group before the join call to prevent engine group deletion (Common_ChangeUnitGroup.sqf:9). The filler is deleted after the join (Common_ChangeUnitGroup.sqf:11).

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LB Filler (WFBE_CL_FNC_UI_Groups_FillUnits, Client_FNC_Groups.sqf:81-99)

Populates any lnbControl with one row per unit. Called with [_units_or_group, _lb_idc]. If passed a GROUP, expands via units _group. Each row contains:

• Column 0 text: "*(name) [vehicleDisplayName]" — prefix * marks players, name is in parentheses, display name in square brackets.
• Column 0 picture: portrait when on foot, picture when in a vehicle (from configFile >> "CfgVehicles" >> typeOf(vehicle _unit)).

The Groups Menu uses IDD 508003 for the current-squad member list and 508007 for the pending-requests list (Client_FNC_Groups.sqf:160, 173, 176, 218-221).

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Known Bug

The "the the group" typo in WFBE_CL_FNC_Groups_JoinAccepted and WFBE_CL_FNC_Groups_JoinDenied was fixed in commit a51f13ef4 (2026-06-24). Current master no longer contains this typo.

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Message Reference

Message key	Direction	Handler	Source
"group-query"	Client → Server	Server_HandleSpecial.sqf:13	Client_FNC_Groups.sqf:126,131
"group-join-request"	Server → Leader's client	HandleSpecial.sqf:23 → WFBE_CL_FNC_Groups_ReceiveRequest	Server_HandleSpecial.sqf:24,26
"group-join-accept"	Leader's client → Requester	HandleSpecial.sqf:20 → WFBE_CL_FNC_Groups_JoinAccepted	Client_FNC_Groups.sqf:206
"group-join-deny"	Leader's client → Requester	HandleSpecial.sqf:21 → WFBE_CL_FNC_Groups_JoinDenied	Client_FNC_Groups.sqf:244 (send via WFBE_CO_FNC_SendToClients)
"group-kick"	Leader's client → Target	HandleSpecial.sqf:22 → WFBE_CL_FNC_Groups_KickedOff	Client_FNC_Groups.sqf:161
"group-join-accept" (AI path)	Server → Requester	HandleSpecial.sqf:20 → WFBE_CL_FNC_Groups_JoinAccepted	Server_HandleSpecial.sqf:34,36

WF_A2_Vanilla mode uses WFBE_CO_FNC_SendToClients (broadcast-filtered-by-UID) for all targeted sends; non-vanilla uses WFBE_CO_FNC_SendToClient (direct). Both modes reach the same handler on the recipient. Common/Init/Init_Common.sqf:149.

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Continue Reading

• Player-AI-Caps-And-Role-Balance — per-side player and AI unit caps that interact with squad formation choices.
• Variable-And-Naming-Conventions — WFBE_C_* / WFBE_Client_* / WFBE_CO_FNC_* naming conventions.
• Client-UI-Systems-Atlas — full IDD map and UI subsystem inventory including the Groups Menu.
• Networking-And-Public-Variables — RequestSpecial, HandleSpecial, and SendToClients channel mechanics.
• AI-Squad-Team-Templates-Catalog — AI team compositions players can join when WFBE_C_AI_TEAMS_ENABLED is active.