(Unity C#) NPC not moving on Grass and other terrain

Question

I have created a NPC that follows the main player. When the player is in a certain range of the NPC, the NPC is supposed to walk, run, and attack based on the distance between the player and the NPC. The NPC has an Animator, box collider, Nav Mesh Agent, Enemy Animator And Enemy Controller Script attached. The settings are as follows,

My problem is that the NPC does not chase the player if there's some sort of grass or ferns on the terrain.

The NPC is set to run all types of terrain using Nav Mesh Agent, moreover the bake settings are like in the image. A video of the issue can be seen here.

The code of the enemy controller (although I doubt that is the issue) is as follows:

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

public enum EnemyState
{
    PATROL,
    CHASE,
    ATTACK
}

public class EnemyController : MonoBehaviour
{

    private EnemyAnimator enemy_Anim;
    private NavMeshAgent navAgent;

    private EnemyState enemy_State;

    public float walk_Speed = 0.5f;
    public float run_Speed = 4f;

    public float chase_Distance = 7f;
    private float current_Chase_Distance;
    public float attack_Distance = 1.8f;
    public float chase_After_Attack_Distance = 2f;

    public float patrol_Radius_Min = 20f, patrol_Radius_Max = 60f;
    public float patrol_For_This_Time = 15f;
    private float patrol_Timer;

    public float wait_Before_Attack = 2f;
    private float attack_Timer;

    private Transform target;

   public GameObject attack_Point;

    //private EnemyAudio enemy_Audio;

    void Awake()
    {
        enemy_Anim = GetComponent<EnemyAnimator>();
        navAgent = GetComponent<NavMeshAgent>();

        target = GameObject.FindWithTag(Tags.PLAYER_TAG).transform;

      //  enemy_Audio = GetComponentInChildren<EnemyAudio>();

    }

    // Use this for initialization
    void Start()
    {

        enemy_State = EnemyState.PATROL;

        patrol_Timer = patrol_For_This_Time;

        // when the enemy first gets to the player
        // attack right away
        attack_Timer = wait_Before_Attack;

        // memorize the value of chase distance
        // so that we can put it back
        current_Chase_Distance = chase_Distance;

    }

    // Update is called once per frame
    void Update()
    {

        if (enemy_State == EnemyState.PATROL)
        {
            Patrol();
        }

        if (enemy_State == EnemyState.CHASE)
        {
            Chase();
        }

        if (enemy_State == EnemyState.ATTACK)
        {
            Attack();
        }

    }

    void Patrol()
    {

        // tell nav agent that he can move
        navAgent.isStopped = false;
        navAgent.speed = walk_Speed;

        // add to the patrol timer
        patrol_Timer += Time.deltaTime;

        if (patrol_Timer > patrol_For_This_Time)
        {

            SetNewRandomDestination();

            patrol_Timer = 0f;

        }

        if (navAgent.velocity.sqrMagnitude > 0)
        {

            enemy_Anim.Walk(true);

        }
        else
        {

            enemy_Anim.Walk(false);

        }

        // test the distance between the player and the enemy
        if (Vector3.Distance(transform.position, target.position) <= chase_Distance)
        {

            enemy_Anim.Walk(false);

            enemy_State = EnemyState.CHASE;

            // play spotted audio
         //   enemy_Audio.Play_ScreamSound();

        }


    } // patrol

    void Chase()
    {

        // enable the agent to move again
        navAgent.isStopped = false;
        navAgent.speed = run_Speed;

        // set the player's position as the destination
        // because we are chasing(running towards) the player
        navAgent.SetDestination(target.position);

        if (navAgent.velocity.sqrMagnitude > 0)
        {

            enemy_Anim.Run(true);

        }
        else
        {

            enemy_Anim.Run(false);

        }

        // if the distance between enemy and player is less than attack distance
        if (Vector3.Distance(transform.position, target.position) <= attack_Distance)
        {

            // stop the animations
            enemy_Anim.Run(false);
            enemy_Anim.Walk(false);
            enemy_State = EnemyState.ATTACK;

            // reset the chase distance to previous
            if (chase_Distance != current_Chase_Distance)
            {
                chase_Distance = current_Chase_Distance;
            }

        }
        else if (Vector3.Distance(transform.position, target.position) > chase_Distance)
        {
            // player run away from enemy

            // stop running
            enemy_Anim.Run(false);

            enemy_State = EnemyState.PATROL;

            // reset the patrol timer so that the function
            // can calculate the new patrol destination right away
            patrol_Timer = patrol_For_This_Time;

            // reset the chase distance to previous
            if (chase_Distance != current_Chase_Distance)
            {
                chase_Distance = current_Chase_Distance;
            }


        } // else

    } // chase

    void Attack()
    {

        navAgent.velocity = Vector3.zero;
        navAgent.isStopped = true;

        attack_Timer += Time.deltaTime;

        if (attack_Timer > wait_Before_Attack)
        {

            enemy_Anim.Attack();

            attack_Timer = 0f;

            // play attack sound
        //    enemy_Audio.Play_AttackSound();

        }

        if (Vector3.Distance(transform.position, target.position) > attack_Distance + chase_After_Attack_Distance)
        {

            enemy_State = EnemyState.CHASE;

        }


    } // attack

    void SetNewRandomDestination()
    {

        float rand_Radius = Random.Range(patrol_Radius_Min, patrol_Radius_Max);

        Vector3 randDir = Random.insideUnitSphere * rand_Radius;
        randDir += transform.position;

        NavMeshHit navHit;

        NavMesh.SamplePosition(randDir, out navHit, rand_Radius, -1);

        navAgent.SetDestination(navHit.position);

    }

    void Turn_On_AttackPoint()
    {
        attack_Point.SetActive(true);
    }

    void Turn_Off_AttackPoint()
    {
        if (attack_Point.activeInHierarchy)
        {
            attack_Point.SetActive(false);
        }
    }

    public EnemyState Enemy_State
    {
        get; set;
    }

} // class

I would appreciate very it if someone could help with such an issue!

EDIT: I forgot to add the grass settings, these are as follows. As you can see there are no colliders.

I am digging some more and apparently the only walkable area is as follows (not entire map), how can I adjust this?

Answer 1

There are 2 fixes. One is mentioned already. And it's to paint off all grass (CTRL + CLICK to DEL selected type). Bake, then CTRL+Z, to get them back.

Other way is to detach the grass from the terain with code and treat them as game objects to be able to modify them accordingly.

Answer 2

Below is how I did:

1. Painted the terrain with all kinds of grasses I needed and trees.
2. Undone all the painted grasses and trees.
3. Baked the navigation mesh(Navmesh) onto the terrain.
4. Redone all the painted grasses and trees.
5. Boom! Work done. :)

Why Do grasses not walkable?

• Grasses have been painted like trees hence they are carved during baking process as trees.

Trick: You have to paint the grasses and all the trees needed, then you have to unpaint all the grasses exceptional for the trees. After that bake the terrain, and undone the process(pressing CTRL + Z several times) until you see the grasses repainted.