an example of how to use the zdoom pathfinding library

ZPathChase.zs

 void A_PathChase(statelabel MeleeState = null, statelabel MissileState = null)
    {
        if (bInChase) return;
        if (bInConversation) return;
 
        bInChase = true;
 
        if (!target || (target && target.health <= 0) || (target && !target.bShootable) )
        { // look for a new target
            bInChase = false;
            SetIdle();
            return;
        }
        reactiontime = 0;
 
        // Melee attack
        if (MeleeState && CheckMeleeRange ())
        {
            if (AttackSound)
            {
                A_StartSound (AttackSound, CHAN_WEAPON);
            }
            bInChase = false;
            SetStateLabel (MeleeState);
            return;
        }
 
        // Missile attack
        if (MissileState && CheckMissileRange())
        {
            bInChase = false;
            SetStateLabel (MissileState);
            return;
        }
 
        // chase towards target
        A_MoveToEx ();
 
        // Active sound
        if (random[MinotaurChase]() < 6)
        {
            PlayActiveSound ();
        }
        
        bInChase=false;
    }