Unity: how do I get a list of prefab tiles from the TileMap?

Question

I'm building a 2D strategy game where I've decided to use TileMap for spaces which characters can traverse. My tiles need to be prefabs, because they will have a script attached to them to store things like their type, cost, any effects they might have on them, name, etc.

To build the TileMap I imported Unity 2D Extras and used its prefab brush. I've actually tried this a couple of ways. First I just manually placed the prefabs and dragged them into the hierarchy under GameTileMap. When that didn't work I thought maybe I needed to do it with the prefab brush so I deleted everything and did the whole thing again that way. Still nothing.

Here is how my Hierarchy looks:

And this is the code I used to try and get that list of all the Tile prefabs I have there:

using UnityEngine.Tilemaps;
using UnityEngine;

public class TileManager : MonoBehaviour {

  public static TileManager instance;
  public Tilemap Tilemap;

  void Awake() {
    if (instance == null) {
      instance = this;
    }
    else if (instance != this) {
      Destroy(gameObject);
    }

    // Do I even have any tiles?
    TileBase[] allTiles = Tilemap.GetTilesBlock(Tilemap.cellBounds);

    // Print positions of each tile if I have any.
    foreach (Vector3Int pos in Tilemap.cellBounds.allPositionsWithin) {
      var localPlace = new Vector3Int(pos.x, pos.y, pos.z);
      Debug.Log(localPlace);
    }

  }
}

The above code is on my TileManager. When run, allTiles list is empty so of course no Debug output is logged.

Question:

Is it possible to get list of tiles that have been painted with the prefab brush?

Answer 1

So to recap:

Initial Problem

• Desire to create a tile map using the TileMap feature with 2d-extras
• Above mentioned tiles should be able to store data about themselves. Data like cost, type, etc.
• Must be able to be referenced in code. i.e read them in from the tile map

Round Peg Square Hole

• Attempted to create these tiles as prefabs.
• Created scripts to attach to each prefab that would store said data
• Attempted to use the prefab brush to paint these tiles as prefabs with the expectation that I could get them from the tilemap in code.

Results

• Prefabs were not added as part of the tilemap

Correct Solution

• Scriptable tiles solved all initial problems

The way this works is you create an editor script call <MyTileType>, in my case TerrainTile. This script is going to add an option in your Assets/Create menu that will have the name you choose and that will create a .asset file with that name.

.asset files can be dragged into the tile palette. Your class will inherit from UnityEngine.Tilemaps.TileBase and in there you can store w/e data you want. Once you have this, the world is yours.

Links that lead me to victory

• Scriptable Tile Docs
• Someone writing a scriptable tile

Some things that weren't immediately obvious if you've never written any editor scripts before

• I needed to set my sprite import settings for my terrain asset's PPU to match the file size (in my case 1024 x 1024) so that it scaled perfectly to my grid.
• Class structure needs to be like:

#if UNITY_EDITOR
using UnityEditor;
#endif

public class TerrainTile : TileBase
{
  // W/e fields you want.
  [SerializeField]
  private Sprite[] _sprite = default;

  [SerializeField]
  private int _cost = 0;

// Must be inside the class you're trying to use
---------------------------------------------------
#if UNITY_EDITOR
  // The following is a helper that adds a menu item to create a MyTile Asset
  [MenuItem("Assets/Create/TerrainTile")]
  public static void CreateTerrainTile() {
    string path = EditorUtility.SaveFilePanelInProject("Save Terrain Tile", "New Terrain Tile", "Asset", "Save Terrain Tile", "Assets");
    if (path == "")
      return;
    AssetDatabase.CreateAsset(ScriptableObject.CreateInstance<TerrainTile>(), path);
  }
#endif
---------------------------------------------------

  public override void RefreshTile(Vector3Int position, ITilemap tilemap) {
    // Read docs for an explanation on this.
    tilemap.RefreshTile(position);
  }

  public override void GetTileData(Vector3Int position, ITilemap tileMap, ref UnityEngine.Tilemaps.TileData tileData) {

    // This is for the preview in the tile palette.
    tileData.sprite = _sprite[0];
  }
}

Its clear that the prefab brush was not built for this. It seems intended to be used to simply paint sparsely used prefabs such as items, scenery, etc.