ObstacleAvoidance.cs

using UnityEngine;
using System.Collections;
using System.Collections.Generic;
using System;

public class ObstacleAvoidance : BTNode
    {
    IBehaviorAI myAI;
    Transform agentTransform;
    float avoidDistance;
    LayerMask avoidlayerMask;
    event InputEventVector3 TurnEvent; 

    public ObstacleAvoidance(IBehaviorAI _myAI, float _avoidDistance, InputEventVector3 _turnEvent, LayerMask _avoidlayerMask)
        {
        myAI = _myAI;
        avoidDistance = _avoidDistance;
        TurnEvent = _turnEvent;
        avoidlayerMask = _avoidlayerMask;
        }

    public override BTNodeStates Evaluate()
        {

        agentTransform = myAI.GetAgentTransform();
        Vector3[] rayDirections =
            {
            agentTransform.forward,
            HelperUtilities.GetDirectionFromAngleInDegrees(10f, agentTransform.forward, agentTransform.right),
            HelperUtilities.GetDirectionFromAngleInDegrees(-10f, agentTransform.forward, agentTransform.right),
            HelperUtilities.GetDirectionFromAngleInDegrees(10f, agentTransform.forward, agentTransform.up),
            HelperUtilities.GetDirectionFromAngleInDegrees(-10f, agentTransform.forward, agentTransform.up),
            (agentTransform.forward + agentTransform.right).normalized,
            (agentTransform.forward - agentTransform.right).normalized,
            (agentTransform.forward + agentTransform.up).normalized,
            (agentTransform.forward - agentTransform.up).normalized,
            (agentTransform.right).normalized,
            (-agentTransform.right).normalized,
            (agentTransform.up).normalized,
            (-agentTransform.up).normalized,
            };

        DrawRays(rayDirections);

        RaycastHit hit;

        if (Physics.Raycast(agentTransform.position, rayDirections[0], out hit, avoidDistance, avoidlayerMask) ||
            Physics.Raycast(agentTransform.position, rayDirections[1], out hit, avoidDistance, avoidlayerMask) ||
            Physics.Raycast(agentTransform.position, rayDirections[2], out hit, avoidDistance, avoidlayerMask) ||
            Physics.Raycast(agentTransform.position, rayDirections[3], out hit, avoidDistance, avoidlayerMask) ||
            Physics.Raycast(agentTransform.position, rayDirections[4], out hit, avoidDistance, avoidlayerMask) ) 
            {

            for(int i = 5; i < rayDirections.Length; i++)
                {
                bool goodTurn = CheckTurn(rayDirections[i]);
                if (goodTurn) return BTNodeStates.SUCCESS; 
                }

            return BTNodeStates.SUCCESS; 

            }

        Vector3 agentPosition = agentTransform.position;
        Vector3 targetPosition = myAI.GetTargetPosition();
        Vector3 desiredHeading = (targetPosition - agentPosition);

        TurnEvent(desiredHeading.x, desiredHeading.y, desiredHeading.z);
      
        return BTNodeStates.SUCCESS; 

        }

    private bool CheckTurn(Vector3 rayDirection)
        {
        RaycastHit hit; 

        if (!Physics.Raycast(agentTransform.position, rayDirection * (avoidDistance / 4), out hit, avoidDistance, avoidlayerMask))
            {
            Vector3 newHeading = rayDirection; 
            Vector3 newTarget = agentTransform.position + (newHeading * (avoidDistance / 4));
            myAI.SetTempTarget(newTarget);
            if (TurnEvent != null) TurnEvent(newHeading.x, newHeading.y, newHeading.z);
            return true;
            }
        return false; 

        }

    private void DrawRays(Vector3[] rayDirections)
        {
        foreach(Vector3 dir in rayDirections)
            {
            Debug.DrawRay(agentTransform.position, dir * avoidDistance, Color.blue);
            }
        }
    }