NavWorld.Equals

Parameters

Returns

bool true if the two NavWorld values refer to the same underlying NavMesh world, and false otherwise.

Description

Determines whether two NavWorld handles refer to the same underlying NavMesh world.

The comparison checks whether both NavWorld values point to the same internal navigation system. A NavWorld obtained from a previous NavWorld.GetDefaultWorld call isn't equal to one obtained after a NavMesh.RemoveAllNavMeshData call, because the underlying world has been destroyed and re-created.

using UnityEngine;
using UnityEngine.AI;
using Unity.AI.Navigation.LowLevel;

public class NavWorldEqualityExample : MonoBehaviour
{
    NavWorld m_World;
    int m_CachedWorldHash;

    void OnEnable()
    {
        m_World = NavWorld.GetDefaultWorld();
        m_CachedWorldHash = m_World.GetHashCode();
        Debug.Log($"Cached the NavMesh world hash {m_CachedWorldHash}");
        CompareNavigationWorldToPrevious();

        // Destroying all the data makes every existing handle to the old world invalid.
        NavMesh.RemoveAllNavMeshData();
        Debug.Log($"Removed all NavMesh data.");

        //m_CachedWorldHash = m_World.GetHashCode();
        //Debug.Log($"Cached the NavMesh world, hash {m_CachedWorldHash}");
        CompareNavigationWorldToPrevious();
    }

    public void CompareNavigationWorldToPrevious()
    {
        NavWorld currentWorld = NavWorld.GetDefaultWorld();

        // Equals, == and != compare the underlying navigation system rather than the struct
        // copy, so two handles obtained from the same world always compare equal.
        if (currentWorld == m_World)
        {
            Debug.Log($"The navigation world is the same as before.");

            // The handles are interchangeable, so keep one and release the duplicate.
            currentWorld.Dispose();
            return;
        }

        Debug.Log($"The world was re-created: hash {m_CachedWorldHash} became {currentWorld.GetHashCode()}");

        // Release the stale handle before replacing it, otherwise its safety handle leaks.
        m_World.Dispose();
        m_World = currentWorld;
        m_CachedWorldHash = m_World.GetHashCode();
    }

    void OnDisable()
    {
        m_World.Dispose();
    }
}

Parameters

Returns

bool true if the two NavWorld values refer to the same underlying NavMesh world, and false otherwise.

Description

Determines whether two NavWorld handles refer to the same underlying NavMesh world.

The comparison checks whether both NavWorld values point to the same internal navigation system. A NavWorld obtained from a previous NavWorld.GetDefaultWorld call isn't equal to one obtained after a NavMesh.RemoveAllNavMeshData call, because the underlying world has been destroyed and re-created.

using UnityEngine;
using UnityEngine.AI;
using Unity.AI.Navigation.LowLevel;

public class NavWorldEqualityExample : MonoBehaviour
{
    NavWorld m_World;
    int m_CachedWorldHash;

    void OnEnable()
    {
        m_World = NavWorld.GetDefaultWorld();
        m_CachedWorldHash = m_World.GetHashCode();
        Debug.Log($"Cached the NavMesh world hash {m_CachedWorldHash}");
        CompareNavigationWorldToPrevious();

        // Destroying all the data makes every existing handle to the old world invalid.
        NavMesh.RemoveAllNavMeshData();
        Debug.Log($"Removed all NavMesh data.");

        //m_CachedWorldHash = m_World.GetHashCode();
        //Debug.Log($"Cached the NavMesh world, hash {m_CachedWorldHash}");
        CompareNavigationWorldToPrevious();
    }

    public void CompareNavigationWorldToPrevious()
    {
        NavWorld currentWorld = NavWorld.GetDefaultWorld();

        // Equals, == and != compare the underlying navigation system rather than the struct
        // copy, so two handles obtained from the same world always compare equal.
        if (currentWorld == m_World)
        {
            Debug.Log($"The navigation world is the same as before.");

            // The handles are interchangeable, so keep one and release the duplicate.
            currentWorld.Dispose();
            return;
        }

        Debug.Log($"The world was re-created: hash {m_CachedWorldHash} became {currentWorld.GetHashCode()}");

        // Release the stale handle before replacing it, otherwise its safety handle leaks.
        m_World.Dispose();
        m_World = currentWorld;
        m_CachedWorldHash = m_World.GetHashCode();
    }

    void OnDisable()
    {
        m_World.Dispose();
    }
}