What is Postal3Script?

Postal3Script, or P3S, is a Finite State Machine (FSM) and a scripting language developed for Postal 3, designed to handle most of the NPC AI and mission scripting.

It allows for a much easier and faster way of doing missions and AI rather than messing around in C++ and doing logic entirely through map entities in Hammer.

With Postal3Script, you can easily do many things that you normally would not be able to do without the source code of the game due to the many useful functions and attributes that are interfaced.

While Postal3Script is a scripting language, it is not as powerful as say, Garry's Mod's LUA, it is heavily limited by the amount of functions available, it's also not as fast as LUA in execution speed unfortunately.

P3S script files are located in Postal III/p3/scripts and use the .p3s file extension, but it can be any extension if wanted. To load and be able to use a p3s script, you must add it to a manifest, in "ai_scripts.txt", found in the previously mentioned folder.

HERE you can download the contents of Postal 3's scripts folder, if you need it for researching purposes, or just out of curiosity.

Postal3Script Example

Constants
{
    Const DONUTS_INCR,1
    Const SOMEBODY_STOLE_MY_DONUTS,15
    Const YES,1
    Const NO,0
}

behavior
{
    name bh_evensuperioractor
    inherited bh_mysuperioractor

    States
    {
        st_mycustomstate
        {
            Group Alert
            Patterns
            {
                pt_default
                {
                    // Only executes when on Alert
                }
            }
        }

        st_nowyallgonnapay
        {
            Group Combat
            Patterns
            {
                pt_default
                {
                    // Only executes when in Combat
                    SetAttr "veryverypissedoff YES"
                    Pattern pt_donuts
                }

                pt_donuts
                {
                    IfAttr "veryverypissedoff == YES Pattern st_nowyallgonnapay.pt_allgood"
                }

                pt_allgood
                {
                    SetAttr "veryverypissedoff NO"
                }
            }
        }
        events
        {
            OnDeath "ExecutePattern st_OnDeath.pt_default"
            OnTimer_tUnstun "Pattern pt_end"
            OnUnconscious "Pattern pt_unconscious"
            OnHostaged "Pattern pt_hostaged"
            OnSprayStunned "Timer tUnstun,SPRAY_UNSTUN_TIMER"
            OnTimer_tScream "ExecutePattern .xpt_SayScream"
            OnUnstunned "Pattern pt_end"
            OnStandUpEnd "Pattern pt_end"
        }

        // Sets on spawn
        st_init
        {
            Group Neutral
            Patterns
            {
                pt_default
                {
                    actions
                    {
                        Senses false
                    }
                }
            }
        }

        // Called continously
        st_start
        {
            Group Neutral
            Patterns
            {
                pt_default
                {
                    actions
                    {
                        // tick
                    }
                }
            }
        }
    }
}

Limitations