Trouble with NavMesh AI.

Unity Engine
,
1

I’ve been trying to create an enemy AI with navMesh so the enemy can follow the player when the player enters the enemies radius. however it’s given me errors when I play test and wont work at all, so I’m at a loss.

i have a navMesh set to the ground which is a terrain that also has a terrain collider which is set to static. The enemy has a navMeshAgent and the enemy and the agent are touching the ground and the navMesh.

when i play test it come up with these errors:

Failed to create agent because it is not close enough to the NavMesh
and
“SetDestination” can only be called on an active agent that has been placed on a NavMesh.
UnityEngine.AI.NavMeshAgent:SetDestination (UnityEngine.Vector3)
EnemyAI:Update () (at Assets/Enemies/EnemyAI.cs:25)

i don’t know what the first one means cause the agent is touching the navMesh so its a bit confusing.

here is the script that runs it;

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

public class EnemyAI : MonoBehaviour
{
    public float visionRadius = 10f;

    Transform target;
    NavMeshAgent agent;

    void Start()
    {
        target = playerManager.instance.player.transform;
        agent = GetComponent<NavMeshAgent>();
    }

    void Update()
    {
        float distance = Vector3.Distance(target.position, transform.position);

        if(distance <= visionRadius)
        {
            agent.SetDestination(target.position);

            if(distance <= agent.stoppingDistance)
            {
                FaceTarget();
            }
        }
    }

    void FaceTarget()
    {
        Vector3 direction = (target.position - transform.position).normalized;
        Quaternion lookRotation = Quaternion.LookRotation(new Vector3(direction.x, 0, direction.z));
        transform.rotation = Quaternion.Slerp(transform.rotation, lookRotation, Time.deltaTime * 5f);
    }

    void OnDrawGizmosSelected()
    {
        Gizmos.color = Color.red;
        Gizmos.DrawWireSphere(transform.position, visionRadius);
    }
}

any help to find what I’m missing would be much appreciated.

2

What version of Unity are you using?

Navmesh does not depend on physics collision, thus a terrain collider is of no help. NavMesh generates its own thing called a “NavMesh Surface”, which needs to be baked. In older versions, the NavMesh Surface is not within the scene, while in the latest version, it is a component to be placed in the scene.

Those errors are likely because you do not have a NavMesh surface, and therefore your NavMesh agent has no idea where to go.