ACE3/addons/overheating/functions/fnc_overheat.sqf

/*
 * Author: Commy2 and esteldunedain
 * Handle weapon fire, heat up the weapon
 *
 * Argument:
 * 0: Unit <OBJECT>
 * 1: Weapon <STRING>
 * 3: Muzzle <STRING>
 * 4: Ammo <STRING>
 * 5: Magazine <STRING>
 * 6: Projectile <OBJECT>
 *
 * Return value:
 * None
 *
 * Public: No
 */
#include "script_component.hpp"

params ["_unit", "_weapon", "", "", "_ammo", "", "_projectile"];
TRACE_4("params",_unit,_weapon,_ammo,_projectile);

//Only do heat calculations every 3 bullets
if (((_unit ammo _weapon) % 3) != 0) exitWith {};

BEGIN_COUNTER(overheat);

// Get physical parameters
private _bulletMass = getNumber (configFile >> "CfgAmmo" >> _ammo >> "ACE_BulletMass");
if (_bulletMass == 0) then {
    // If the bullet mass is not configured, estimate it
    _bulletMass = 3.4334 + 0.5171 * (getNumber (configFile >> "CfgAmmo" >> _ammo >> "hit") + getNumber (configFile >> "CfgAmmo" >> _ammo >> "caliber"));
};
//https://en.wikipedia.org/wiki/Physics_of_firearms - Projectile motion is roughly equal to Barrel heat
//Muzzle Engergy = 1/2 * m * v^2 (1/2 * 0.001 g/kg * bulletMass (grams) * v^2)
//Multiple by 3 becase we only calc every 3rd bullet: (3 * 1/2 * 0.001) = 0.0015
private _energyIncrement = 0.0015 * _bulletMass * (vectorMagnitudeSqr velocity _projectile);

TRACE_2("heat",_bulletMass,_energyIncrement);

[_unit, _weapon, _energyIncrement] call FUNC(updateTemperature);

END_COUNTER(overheat);