Show correct elev for mortar with no ammo (#4478)

Fix #3757

addons/mk6mortar/functions/fnc_handlePlayerVehicleChanged.sqf

@@ -46,8 +46,8 @@ if (_lastFireMode != -1) then {
 
 [{
     private ["_chargeText", "_currentChargeMode", "_currentFireMode", "_display", "_elevDeg", "_elevationDiff", "_lookVector", "_notGunnerView", "_realAzimuth", "_realElevation", "_upVectorDir", "_useMils", "_weaponDir"];
-    PARAMS_2(_args,_pfID);
-    EXPLODE_2_PVT(_args,_mortarVeh,_fireModes);
+    params ["_args", "_pfID"];
+    _args params ["_mortarVeh", "_fireModes"];
 
     if ((vehicle ACE_player) != _mortarVeh) then {
         [_pfID] call CBA_fnc_removePerFrameHandler;
@@ -80,7 +80,19 @@ if (_lastFireMode != -1) then {
         //(looking at the sky VS looking at ground will radicaly change fire direction because BIS)
         _realAzimuth = -1;
         _realElevation = -1;
-        if ((ctrlText (_display displayCtrl 173)) == "--") then {
+
+        private _useRealWeaponDir = (ctrlText (_display displayCtrl 173)) == "--";
+        if (_useRealWeaponDir && {(_mortarVeh ammo (currentWeapon _mortarVeh)) == 0}) then {
+            // With no ammo, distance display will be empty, but gun will still fire at wonky angle if aimed at ground
+            private _testSeekerPosASL = AGLtoASL (positionCameraToWorld [0,0,0]);
+            private _testSeekerDir = _testSeekerPosASL vectorFromTo (AGLtoASL (positionCameraToWorld [0,0,1]));
+            private _laserRange = [_testSeekerPosASL, _testSeekerDir, _mortarVeh] call EFUNC(laser,shootRay);
+            _laserRange params ["", ["_rayDistance", -5]]; // ToDo: move shootRay to common
+            TRACE_2("",_rayDistance,viewDistance);
+            _useRealWeaponDir = _rayDistance > viewDistance; // If we are looking at infinity (based on viewDistance)
+        };
+
+        if (_useRealWeaponDir) then {
             //No range (looking at sky), it will follow weaponDir:
             _weaponDir = _mortarVeh weaponDirection (currentWeapon _mortarVeh);
             _realAzimuth = (_weaponDir select 0) atan2 (_weaponDir select 1);