ACE3/addons/atragmx/functions/fnc_recalculate_muzzle_velocity.sqf

/*
 * Author: Ruthberg
 * Recalculates the muzzle velocity based on the muzzle velocity vs. temperature interpolation input
 *
 * Arguments:
 * parse input <BOOL>
 * update display <BOOL>
 *
 * Return Value:
 * None
 *
 * Example:
 * call ace_atragmx_fnc_recalculate_muzzle_velocity
 *
 * Public: No
 */
#include "script_component.hpp"

params ["_parseInput", "_updateDisplay"];

if (_parseInput) then {
    [] call FUNC(parse_input);
};

private _lookupTable = [];
{
    if ((_x select 1) > 0) then {
        _lookupTable pushBack _x;
    };
} forEach (GVAR(workingMemory) select 18);

private _lookupTableSize = count _lookupTable;
if (_lookupTableSize < 2) exitWith {};
_lookupTable sort true;

private _lowerIndex = -1;
private _upperIndex = -1;
for "_index" from 1 to (_lookupTableSize - 1) do {
    _upperIndex = _index;
    _lowerIndex = _upperIndex - 1;
    if (((_lookupTable select _index) select 0) >= GVAR(temperature)) exitWith {};
};

private _lowerTemperature    = (_lookupTable select _lowerIndex) select 0;
private _upperTemperature    = (_lookupTable select _upperIndex) select 0;
private _lowerMuzzleVelocity = (_lookupTable select _lowerIndex) select 1;
private _upperMuzzleVelocity = (_lookupTable select _upperIndex) select 1;
private _muzzleVelocity = _lowerMuzzleVelocity;
if (_lowerTemperature != _upperTemperature) then {
    private _slope = (_upperMuzzleVelocity - _lowerMuzzleVelocity) / (_upperTemperature - _lowerTemperature);
    _muzzleVelocity = _lowerMuzzleVelocity + (GVAR(temperature) - _lowerTemperature) * _slope;
};
_muzzleVelocity = 100 max _muzzleVelocity min 1400;

if (_muzzleVelocity != GVAR(workingMemory) select 1) then {
    GVAR(workingMemory) set [1, _muzzleVelocity];
    if (_updateDisplay) then {
        call FUNC(update_gun);
        call FUNC(update_gun_ammo_data);
    };
};