AI distance from Player

Hello,

In my scene I have a First Person Controller, Enemy 1 and Enemy 2. I have applied the following scripts to Enemy 1 and Enemy 2: Character Controller, AI, AIAnimation, Character Damage.

Enemy 1 comes close to the First Person Controller but Enemy 2 stays further away.

I would like Enemy 2 to come closer to the First Person Controller. Which setting or script determines the distance for AI character.

Thank you

The distance is determined by Vector3.Distance. An example from the unity script website is below.

var other : Transform;
if (other) {
    var dist = Vector3.Distance(other.position, transform.position);
    print ("Distance to other: " + dist);
}

You could then say:

 function Update () {
if (dist < 10)
{
   //attack enemy
}
}

Don't you already have the distance setting in your script? The line below is what I was suggesting although I suppose you could have another line saying if Vector3.Distance < attackRange, then do something else.

if (Vector3.Distance(transform.position, target.position) > attackRange)
    return false;

I am not quite sure I understand what it is you are asking.

Thank you for replying macdude 2. I tried pasting your suggested code but received an error message. Where would I place the suggested script?

My apologise but lm not familiar with Unity scripting. Posted is the AI script l'm using.

var speed = 3.0;
var rotationSpeed = 5.0;
var shootRange = 15.0;
var attackRange = 30.0;
var shootAngle = 4.0;
var dontComeCloserRange = 5.0;
var delayShootTime = 0.35;
var pickNextWaypointDistance = 2.0;
var target : Transform;

private var lastShot = -10.0;

// Make sure there is always a character controller
@script RequireComponent (CharacterController)

function Start () {
    // Auto setup player as target through tags
    if (target == null && GameObject.FindWithTag("Player"))
        target = GameObject.FindWithTag("Player").transform;

    Patrol();
}

function Patrol () {
    var curWayPoint = AutoWayPoint.FindClosest(transform.position);
    while (true) {
        var waypointPosition = curWayPoint.transform.position;
        // Are we close to a waypoint? -> pick the next one!
        if (Vector3.Distance(waypointPosition, transform.position) < pickNextWaypointDistance)
            curWayPoint = PickNextWaypoint (curWayPoint);

        // Attack the player and wait until
        // - player is killed
        // - player is out of sight     
        if (CanSeeTarget ())
            yield StartCoroutine("AttackPlayer");

        // Move towards our target
        MoveTowards(waypointPosition);

        yield;
    }
}

function CanSeeTarget () : boolean {
    if (Vector3.Distance(transform.position, target.position) > attackRange)
        return false;

    var hit : RaycastHit;
    if (Physics.Linecast (transform.position, target.position, hit))
        return hit.transform == target;

    return false;
}

function Shoot () {
    // Start shoot animation
    animation.CrossFade("shoot", 0.3);

    // Wait until half the animation has played
    yield WaitForSeconds(delayShootTime);

    // Fire gun
    BroadcastMessage("Fire");

    // Wait for the rest of the animation to finish
    yield WaitForSeconds(animation["shoot"].length - delayShootTime);
}

function AttackPlayer () {
    var lastVisiblePlayerPosition = target.position;
    while (true) {
        if (CanSeeTarget ()) {
            // Target is dead - stop hunting
            if (target == null)
                return;

            // Target is too far away - give up 
            var distance = Vector3.Distance(transform.position, target.position);
            if (distance > shootRange * 3)
                return;

            lastVisiblePlayerPosition = target.position;
            if (distance > dontComeCloserRange)
                MoveTowards (lastVisiblePlayerPosition);
            else
                RotateTowards(lastVisiblePlayerPosition);

            var forward = transform.TransformDirection(Vector3.forward);
            var targetDirection = lastVisiblePlayerPosition - transform.position;
            targetDirection.y = 0;

            var angle = Vector3.Angle(targetDirection, forward);

            // Start shooting if close and play is in sight
            if (distance < shootRange && angle < shootAngle)
                yield StartCoroutine("Shoot");
        } else {
            yield StartCoroutine("SearchPlayer", lastVisiblePlayerPosition);
            // Player not visible anymore - stop attacking
            if (!CanSeeTarget ())
                return;
        }

        yield;
    }
}

function SearchPlayer (position : Vector3) {
    // Run towards the player but after 3 seconds timeout and go back to Patroling
    var timeout = 3.0;
    while (timeout > 0.0) {
        MoveTowards(position);

        // We found the player
        if (CanSeeTarget ())
            return;

        timeout -= Time.deltaTime;
        yield;
    }
}

function RotateTowards (position : Vector3) {
    SendMessage("SetSpeed", 0.0);

    var direction = position - transform.position;
    direction.y = 0;
    if (direction.magnitude < 0.1)
        return;

    // Rotate towards the target
    transform.rotation = Quaternion.Slerp (transform.rotation, Quaternion.LookRotation(direction), rotationSpeed * Time.deltaTime);
    transform.eulerAngles = Vector3(0, transform.eulerAngles.y, 0);
}

function MoveTowards (position : Vector3) {
    var direction = position - transform.position;
    direction.y = 0;
    if (direction.magnitude < 0.5) {
        SendMessage("SetSpeed", 0.0);
        return;
    }

    // Rotate towards the target
    transform.rotation = Quaternion.Slerp (transform.rotation, Quaternion.LookRotation(direction), rotationSpeed * Time.deltaTime);
    transform.eulerAngles = Vector3(0, transform.eulerAngles.y, 0);

    // Modify speed so we slow down when we are not facing the target
    var forward = transform.TransformDirection(Vector3.forward);
    var speedModifier = Vector3.Dot(forward, direction.normalized);
    speedModifier = Mathf.Clamp01(speedModifier);

    // Move the character
    direction = forward * speed * speedModifier;
    GetComponent (CharacterController).SimpleMove(direction);

    SendMessage("SetSpeed", speed * speedModifier, SendMessageOptions.DontRequireReceiver);
}

function PickNextWaypoint (currentWaypoint : AutoWayPoint) {
    // We want to find the waypoint where the character has to turn the least

    // The direction in which we are walking
    var forward = transform.TransformDirection(Vector3.forward);

    // The closer two vectors, the larger the dot product will be.
    var best = currentWaypoint;
    var bestDot = -10.0;
    for (var cur : AutoWayPoint in currentWaypoint.connected) {
        var direction = Vector3.Normalize(cur.transform.position - transform.position);
        var dot = Vector3.Dot(direction, forward);
        if (dot > bestDot && cur != currentWaypoint) {
            bestDot = dot;
            best = cur;
        }
    }

    return best;
}