MP5 - Basic logic of overheating system

void CMP5::Spawn( )
{
    // Spawn code here
    m_iHeat = 0; // Shepard : By default our weapon hasn't heated
}

void CMP5::PrimaryAttack()
{
    // Shepard : Cool down our weapon if we can't fire
    Cooldown();

    // Check if firing underwater and gun is empty code here

    // Shepard : deny weapon firing if weapon has overheated
    if ( m_iHeat >= 100 )
    {
        PlayEmptySound();
        m_flNextPrimaryAttack = 0.15f;
        return;
    }

    // Shepard : Increment heating (and prevent to go higher than 100%)
    m_iHeat += 5;
    if ( m_iHeat > 100 )
        m_iHeat = 100;

    // Effects, event, firing, accuracy code here

#ifndef CLIENT_DLL
    m_flCooldownTime = gpGlobals->time + 3.0f; // Shepard : This forces the player to wait 3 seconds for the weapon to cool down
#endif
}

void CMP5::WeaponIdle( void )
{
    // Shepard : Cool down the weapon (if we can)
    Cooldown();

    // Idle animation code here
}

// Shepard : Cool down the weapon
void CMP5::Cooldown( void )
{
    // For debugging purposes, you can remove that and replace by your HUD update code
#ifndef CLIENT_DLL
    ALERT( at_console, "Heat = %d - Game time = %f - Cool down time = %2f\n", m_iHeat, gpGlobals->time, m_flCooldownTime );
#endif

    // Disallow negative values
    if ( m_iHeat <= 0 )
    {
        //m_iHeat = 0; // If you decrement by 1%, that line is NOT needed, otherwise you'll need it (you don't want to have -1%)
        return;
    }

    // Perform the real cool down
    while ( m_iHeat > 0 && m_flCooldownTime < gpGlobals->time)
    {
        m_iHeat--;
        m_flCooldownTime += 0.5f;
    }
}