Tiles created with SetTile, not rendering when game is running

I have four tilemaps in my 2D URP project:

Ground, Walls, Path, Selection

They have their own ordering (0, 1, 2, 3 respectively).

Now when a user mouse overs a grid, I want to draw a highlight tile on the Selection tilemap.

I wrote this code:

Code (CSharp):

1.    
2. public class GridController  : MonoBehaviour
3. {
4.     [SerializeField] Tilemap selectionHighlights;
5.     [SerializeField] Tile selectionTile;
6.  
7.     private Grid grid;
8.     // Start is called before the first frame update
9.     void Start()
10.     {
11.         grid = GetComponent<Grid>();
12.     }
13.  
14.     Vector3Int GetMousePosition()
15.     {
16.         Vector3 mouseWorldPos = Camera.main.ScreenToWorldPoint(Input.mousePosition);
17.         return grid.WorldToCell(mouseWorldPos);
18.     }
19.  
20.     // Update is called once per frame
21.     void Update()
22.     {
23.         var mousePos = GetMousePosition();
24.         if (Input.GetMouseButtonDown(0))
25.         {
26.             Debug.Log("Mouse position over " + mousePos.x + "/" + mousePos.y);
27.             selectionHighlights.SetTile(mousePos, selectionTile);
28.         }
29.     }
30. }
31.  

When I run the game, nothing happens. I see the log message, but not the tile being created.

If I PAUSE the game, the tiles I created are visible. If I continue playing the game, the tiles disappear.

I'm not sure what I'm doing wrong, anyone have a clue?

 

Well, by setting my Camera's far clipping plane to 0, instead of 0.3, this seemed to resolve the issue. I can't say why it did though, since I'm still fairly new to Unity. Perhaps someone who reads this could elucidate further?

 

One way I've had things go wrong is this line:

Vector3 mouseWorldPos = Camera.main.ScreenToWorldPoint(Input.mousePosition);

What happens here is that the camera's z position is preserved, which is often -10. That may not be visible to the camera.

Add this:

mouseWorldPos.z = 0f;

That is good practice in general because you likely don't want to set your tiles to (x, y, -10) accidentally.