Mesh as Navmesh?

Sadly navmesh are limited, so I don't think it's possible right now. But as a workaround you can apply a translation offset to the renderer of your navmesh agent. Here the code I used for my agents on a moving boat using navmesh. The code below manage only one moving platform and modification are required to a more advance navigation.

 //Put on your moving platform
 public class NavMeshDynamic : MonoBehaviour 
 {
     protected Vector3 initialPosition;
     protected Quaternion initialRotation;
 
     // Use this for initialization
     void Awake ()
     {
         initialPosition = transform.position;
         initialRotation = transform.rotation;
     }
 
     public Vector3 getOffsetPosition()
     {
         return transform.position - initialPosition;
     }
 
     public Quaternion getOffsetRotation()
     {
         return transform.rotation * Quaternion.Inverse(initialRotation);
     }
 
     public Vector3 getCorrectedPosition(Vector3 position)
     {
         return position + (transform.position - initialPosition);
     }
 
     public Quaternion getCorrectedRotation(Quaternion rotation)
     {
         return rotation * transform.rotation * Quaternion.Inverse(initialRotation);
     }
 
     public Vector3 getInitialPosition()
     {
         return initialPosition;
     }
 
     public Quaternion getInitialRotation()
     {
         return initialRotation;
     }
 }

 //Put on your renderer (should be child of your navmesh agent)
 public class NavMeshOffset : MonoBehaviour
 {
     public NavMeshDynamic navMeshDynamic;
     public GameObject objectToMove;
 
     protected Quaternion initialObjectRotation;
 
     void Awake()
     {
         initialObjectRotation = objectToMove.transform.rotation;
     }
 
     void LateUpdate() 
     {
         //Correct position from object rotation
         Vector3 offsetDirection = objectToMove.transform.position - navMeshDynamic.getInitialPosition();
         Vector3 offsetDirectionRotated = navMeshDynamic.getOffsetRotation() * offsetDirection;
         transform.position = navMeshDynamic.transform.position + offsetDirectionRotated;
         transform.rotation = objectToMove.transform.rotation *  navMeshDynamic.getOffsetRotation();
     }
 }

Here my hierachy :

• boat (NavMeshDynamic)

• agent (NavMeshAgent)
  • offset (NavMeshOffset: objectToMove : agent)

    • rig
      

  • skinrenderer

Hope it's help you.