Ядро плагина Effect Calculator 2.1

public void ModifyDamage(int client, float &value)
{
    if(IsPlayerAlive(client))
    {
        int val = 100 - GetClientHealth(client);
        if(val > 0)
            value += float(val);
    }
    else
        value += 1.0;
}

public void OnLibraryAdded(const char[] library)
{
    if(!strcmp(library))    ECalc_Hook2("damage", "lesshpmoredmg", ModifyDamage);
}

public void OnClientPutInServer(int client)
{
    SDKHookEx(client, SDKHook_OnTakeDamage, OnEntityTakeDamage)
}

public Action OnEntityTakeDamage(int victim, int& attacker, int& inflictor, float& damage, int& damagetype, int& weapon, float damageForce[3], float damagePosition[3], int damagecustom)
{
    if(effect != -1 && (0 < attacker <= MaxClients || 0 < victim <= MaxClients))
    {
        damage *= ECalc_Run2(attacker, "damage");
        return Plugin_Changed
    }
    return Plugin_Continue
}

any dmginfo[5];
        dmginfo[1] = inflictor;
        dmginfo[2] = damage;
        dmginfo[3] = damagetype;
        dmginfo[4] = weapon;
        damage *= ECalc_Run2(attacker, "damage", dmginfo, sizeof dmginfo);

view_as<float>(dmginfo[2]) *= 2.0

public void ModifyDamage(int client, float &value, const char[] effect, any[] data, int size)
{
    if(size < 5)    return;
    if(IsPlayerAlive(client))
    {
        char sBuffer[8];
        int weapon = data[4];
        if(!IsValidEntity(weapon))    return;
        GetEntityNetClass(weapon, sBuffer, sizeof sBuffer);
        if(strcmp(sBuffer, "CKnife", 6))    return;
        int val = 100 - GetClientHealth(client);
        if(val > 0)
            value += float(val);
    }
}

/***
 *    Hook callback typeset
***/
typeset ECalc_HookApplyCallBack    {
    function Action (int client); // return Plugin_Stop on applying
}

typeset ECalc_HookCallBack    {
    // old
    //function void (any[] data, int size, float &value);
    //function void (any[] data, int size, float &value, const char[] effect);

    // new
    function void (int client, float &value, const char[] effect, any[] data, int size);
    function void (int client, float &value, const char[] effect);
    function void (int client, float &value);
}

/***
 *    ECalc_Hook            Hook calculating effect multiplier
 *
 *    @param    effect        Name of effect
 *    @param    mult_name    Name of multiplier (same multipliers will sum)
 *    @param    func        Hook callback (See ECalc_HookCallBack)
 *    @param    remove        If true, your hook will be removed
 *
 *    @no return
***/
native void ECalc_Hook2(const char[] effect, const char[] mult_name, ECalc_HookCallBack func, bool remove = false);

/***
 *    ECalc_Hook            Hook calculating effect multiplier
 *
 *    @param    effect        Name of effect
 *    @param    mult_name    Name of multiplier (same multipliers will sum)
 *    @param    func        Hook callback (See ECalc_HookCallBack)
 *    @param    remove        If true, your hook will be removed
 *
 *    @no return
***/
native void ECalc_HookApply(const char[] effect, ECalc_HookApplyCallBack func, bool remove = false);

/***
 *    ECalc_Run            Calculating effects final multiplier
 *
 *    @param    effect        Effect ID (not name, for faster work)
 *    @param    data        Dynamic array for data
 *    @param    size        Count of values in array
 *
 *    @return    multiplier    Final multiplier of this effect, ready to use
**/
native float ECalc_Run2(int client, const char[] effect, any[] data = NULL_VECTOR, int size = 0);

/***
 *    ECalc_Recalculate    Functions calls to recalculate some effects of player
 *
 *    @param    effect        client
 *    @param    effect        Name of effect
 *
 *    @return                true if effect applied
***/
native bool ECalc_Apply(int client, const char[] effect);
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