Sensors and Activities - Unity AI Programming Essentials - page 86

gold; so, add another constraint node with the Expressiongold != null value and a
move node below it that has a Move Target value of gold . Here is how the behavior
tree with the detect node settings will look:
If you run the demo now, the ship will move to the gold when it sees it. However, let's
change this so that the ship goes back to patrolling after the pickup. Make sure that
both root and selector nodes are set to Forever for their Repeat type. Then, create
a new custom action node (like in Chapter 3 , Behavior Trees ) and put it under the
move node for the gold. Create a new class for the custom action and call it Pick-
UpGold . Set its code to this:
using UnityEngine;
using RAIN.Core;
using RAIN.Action;
[RAINAction]
public class PickUpGold : RAINAction
{
public PickUpGold()
{
actionName = "PickUpGold";
}
public override void Start(AI ai)
{
base.Start(ai);
GameObject gold =
ai.WorkingMemory.GetItem<GameObject>("gold");