trade: calc damage %, return new cost

Sources/epoch_code/compile/traders/EPOCH_calcDamageCost.sqf

@@ -0,0 +1,35 @@
+/*
+	Author: Raimonds Virtoss - EpochMod.com
+
+    Contributors:
+
+	Description: Takes in total cost of vehicle and returns new price with damage % taken into account
+
+    Licence:
+    Arma Public License Share Alike (APL-SA) - https://www.bistudio.com/community/licenses/arma-public-license-share-alike
+
+    Github:
+    https://github.com/EpochModTeam/Epoch/tree/release/Sources/epoch_code/gui/scripts/favBar/epoch_favBar_refresh.sqf
+
+	Usage: [_vehOBJ,_costINT] call EPOCH_calcDamageCost;
+*/
+
+private ["_dmg","_hitPoints"];
+params [["_obj",objNull, [objNull]],["_cost",0, [0]]];
+
+if (_obj isEqualTo objNull) exitWith {-1};
+
+_hitPoints = getAllHitPointsDamage _obj;
+_totalHPoints = count (_hitPoints select 1);
+_totalDamagedPoints = 0;
+{
+	_dmg = _hitPoints select 2 select _forEachIndex;
+	if (_dmg > 0) then {
+		_totalDamagedPoints = _totalDamagedPoints +1;
+	};
+} forEach (_hitPoints select 1);
+
+_math = round (_totalDamagedPoints / _totalHPoints * 100);
+_newCost = _cost - _math;
+
+_newCost 

Sources/epoch_config/Configs/CfgClientFunctions.hpp

@@ -72,6 +72,7 @@ class CfgClientFunctions
             class tradeFilter {};
             class takeCrypto {};
             class startBankTransfer {};
+			class calcDamageCost {};
         };
         class interface_event_handlers
         {