Deployable Bipod Weapon Resting

Deployable Bipod / Weapon Resting

Source-verified 2026-06-21 against master 0139a346. Paths relative to Missions/[55-2hc]warfarev2_073v48co.chernarus/ unless noted. Arma 2 OA 1.64.

A client-side, player-facing "deploy bipod" / weapon-resting mechanic. While carrying one of a fixed whitelist of machine guns and sniper rifles, a player who presses TAB in a valid stance (prone, or crouched directly behind a short solid object) has their weapon recoil zeroed and gets an audible/visual confirmation. The entire feature lives in a single function, Common\Functions\Common_Bipod.sqf (header credits // -WASP- and // 3JIbIDEHb aka Smirnoff_ICE, Common_Bipod.sqf:1-2), is execVM'd once at client init, and is invisible to the server — it only adjusts the local player's recoil coefficient.

Wiring and lifecycle

The function is launched once per client during client init, after the local HandleDamage rearmor handler is attached:

Step	Where	Detail
Launch	Client\Init\Init_Client.sqf:66	[] execVM "Common\Functions\Common_Bipod.sqf"; — fire-and-forget, no return value used, no global handle stored.
Wait for UI	Common_Bipod.sqf:5	waituntil {!isnull (finddisplay 46)}; — blocks until the main mission display (IDD 46) exists, so the KeyDown handler attaches to a live display.
Attach key hook	Common_Bipod.sqf:5	(findDisplay 46) displayAddEventHandler ["KeyDown","_this select 1 call Bipod_ON; false"]; — the handler passes the DIK key code (_this select 1) into Bipod_ON and returns false, so the keypress is not consumed (TAB still performs its normal in-game function).
Define handler	Common_Bipod.sqf:7-65	Bipod_ON = { switch (_this) do { ... } }; — a global code value invoked on every key-down event.

Because Bipod_ON is a global and the KeyDown handler is bound to display 46, the function runs on each player's machine only. There is no server call, no publicVariable, and no setVehicleInit — nothing about bipod state propagates off the local client.

The TAB case and stance gate

Bipod_ON is called for every key-down on display 46 but only acts on one key:

Element	Path:line	Behavior
Switch on key code	Common_Bipod.sqf:8	switch (_this) do where _this is the raw DIK code from the KeyDown event.
TAB case	Common_Bipod.sqf:11	case 15: — DIK code 15 is TAB (the inline comment at Common_Bipod.sqf:10 reads "For using bipod hit TAB"). All other keys fall through with no effect.
Current weapon	Common_Bipod.sqf:12	_weapon = currentWeapon player; — captured for the whitelist test below.
Target object	Common_Bipod.sqf:48	_behind = cursorTarget; — the object the player is currently looking at, used as the "rest" surface.
Object size	Common_Bipod.sqf:49	_size = sizeOf (typeOf _behind); — the configured bounding size of that object's class.
Proximity/size test	Common_Bipod.sqf:50	Stands_behind = ((player distance _behind < _size/2.2) && (_size < 16.2)); — true when the player is close to a small object (the _size < 16.2 cap rejects large structures).
Prone path	Common_Bipod.sqf:51	Lying_stand = ((animationState player == "amovppnemstpsraswrfldnon") && (_weapon in _affected)); — prone rifle-down idle animation and a whitelisted weapon.
Crouch path	Common_Bipod.sqf:52	Crouch_stand = ((Stands_behind) && (_weapon in _affected) && (!(typeof _behind isKindOf "Man")) && (!(typeof _behind isKindOf "Air"))); — close to a small object, whitelisted weapon, and the rested object is neither a man nor an aircraft.
Apply	Common_Bipod.sqf:53-55	if (Lying_stand or Crouch_stand) then { ... }; — only one of the two gates needs to pass.

So there are exactly two ways to "deploy": be prone with a supported weapon (no object required), or be near a small solid prop (vehicle/structure under the size cap, not a person or aircraft) with a supported weapon.

Effect when the gate passes

Action	Path:line	Effect
On-screen text	Common_Bipod.sqf:54	SetBipodOn = HintSilent (localize "str_bipod"); — a silent hint. Note: the str_bipod key is commented out in stringtable.xml:62-73 (the <!--<Key ID="str_bipod"> block, original text "Bipod deployed"), so localize "str_bipod" returns the literal string "str_bipod" at runtime rather than the intended "Bipod deployed". The hint result is stored in the global SetBipodOn, which is never read anywhere else.
Zero recoil	Common_Bipod.sqf:54	player setUnitRecoilCoefficient 0; — the actual rest effect: removes weapon recoil for the local player.
Confirm sound	Common_Bipod.sqf:54	player say "Bipod_ON"; — plays the mission sound Bipod_ON, defined at Sounds/description.ext:66-69 (name = "Bipod_ON"; sound[] = {"\Sounds\Bipod_ON-10.ogg", 10, 1};).
Reset recoil	Common_Bipod.sqf:64	player setUnitRecoilCoefficient 1; — runs at the end of the TAB case every time it is invoked, restoring normal recoil. Because the same TAB press both sets 0 (inside the if) and then unconditionally restores 1 at case exit, the zeroed-recoil state is momentary unless re-asserted; a player effectively pulses recoil off by holding/tapping TAB.

The private declaration at Common_Bipod.sqf:3 (private ["_unit","_weapon","_affected","_behind","_size"]) lists _unit, which is never assigned or used inside the function. The globals Stands_behind, Lying_stand, Crouch_stand, and SetBipodOn are created without private and leak into mission namespace, but none are read outside this file (verified by grep across *.sqf).

Supported-weapon whitelist

_affected (Common_Bipod.sqf:13-47) is a hard-coded array of weapon class names; only currentWeapon player matching one of these enables the rest. The list mixes BAF/PMC DLC weapons, OA base sniper rifles, and squad automatic weapons:

Category	Classes (verbatim from Common_Bipod.sqf:13-47)
Heavy/anti-materiel sniper	ksvk, m107, m107_TWS_EP1, BAF_AS50_scoped, BAF_AS50_TWS, BAF_LRR_scoped, BAF_LRR_scoped_W, PMC_AS50_scoped, PMC_AS50_TWS
Marksman / sniper rifles	BAF_L86A2_ACOG, M110_NVG_EP1, M110_TWS_EP1, M24, M24_des_EP1, M40A3, m8_sharpshooter, SCAR_H_LNG_Sniper, SCAR_H_LNG_Sniper_SD
GPMG / MMG	BAF_L7A2_GPMG, M240, m240_scoped_EP1, M60A4_EP1, Mk_48, Mk_48_DES_EP1, Pecheneg, PK
SAW / LMG	BAF_L110A1_Aim, M249, M249_EP1, M249_m145_EP1, M249_TWS_EP1, m8_SAW, MG36, MG36_camo, RPK_74

Any weapon not on this exact list (including newer/modded MGs and snipers) gets no rest effect even in a valid stance. The list is a literal, so adding support means editing Common_Bipod.sqf directly.

Dead/debug code in the same case

Below the TAB block, a case 57: ("Hit SPACE", Common_Bipod.sqf:57) and a closing debug hint line (Common_Bipod.sqf:61) are fully commented out, along with a trailing HintSilent ""; (Common_Bipod.sqf:63). They were a development bounding-box probe and are inert. The only live key is TAB.

Continue Reading

• Engine Stealth & Fuel Toggle Reference — a sibling client-side key/action toggle of similar shape.
• Earplugs Audio Toggle Reference — another local, player-only quality-of-life toggle.
• Client UI HUD And Menus — where display 46 KeyDown hooks and client HUD wiring are catalogued.
• Mission Entrypoints And Lifecycle — the Init_Client.sqf client-init chain that execVMs this function.
• Faction Unit And Vehicle Roster Catalog — context for the weapon classes in the whitelist.