Unity 2D Tilemap Custom Hexagonal Rule Tile

Question

I'm looking for a way to create a new type of hexagonal rule tile to do something rather simple and specific. I want to create a hex rule tile capable of automatically choosing a sprite based on which other types of hexagonal tiles are adjacent to it. The default hexagonal rule tiles allow you to specify the sprite when a given tile is bordered by that same tile type on each side, but this is insufficient for my purposes.

What I ultimately want is to create a coast tile that will detect which sides are bordered by ocean tiles and choose the correct hex sprite based on that. Something like this, but with the ability to specify ocean tiles, not just the same tile type as indicated by the green arrows:

I can see Unity's default code for hexagonal rule tiles in their github repo, but have no idea how to go about overriding this exactly: https://github.com/Unity-Technologies/2d-extras/blob/master/Runtime/Tiles/HexagonalRuleTile/HexagonalRuleTile.cs

This is a relatively new subject in Unity, but any help or guidance would be much appreciated.

Mir Mir · Accepted Answer · 2020-03-25T04:15:34

Ok, figured this out after some deep googling and trial and error. All I needed was this inheriting class that overrides the RuleMatch method. Hopefully this will be useful to others.

using System;
using UnityEngine;
using UnityEngine.Tilemaps;

[Serializable]
[CreateAssetMenu(fileName = "CoastHexagonTile", menuName = "Tiles/CoastHexagonTile")]
public class CoastHexagonTile : HexagonalRuleTile<CoastHexagonTile.Neighbor>
{
    public bool isOcean;
    public bool isCoast;

    public class Neighbor : TilingRule.Neighbor
    {
        public const int IsOcean = 3;
        public const int IsNotOcean = 4;
        public const int IsCoast = 5;
        public const int IsNotCoast = 6;
    }

    /// <summary>
    /// Checks if there is a match given the neighbor matching rule and a Tile.
    /// </summary>
    /// <param name="neighbor">Neighbor matching rule.</param>
    /// <param name="other">Tile to match.</param>
    /// <returns>True if there is a match, False if not.</returns>
    public override bool RuleMatch(int neighbor, TileBase tile)
    {
        var other = tile as CoastHexagonTile;
        switch (neighbor)
        {
            case Neighbor.IsOcean:
                return other && other.isOcean;
            case Neighbor.IsNotOcean:
                return other && !other.isOcean;
            case Neighbor.IsCoast:
                return other && other.isCoast;
            case Neighbor.IsNotCoast:
                return other && !other.isCoast;
        }
        return base.RuleMatch(neighbor, tile);
    }
}

Edit: Unfortunately it looks like not all of the rule tiles are obeying the rules for some reason. I am setting each tile programmatically on a large map, I wonder if that's basically the cause.

Additional Edit: Ok, I found that in order for tiles to be rendered correctly, the Tilemap.RefreshAllTiles() method needs to be called. I think this is only true when tiles are moved around and set programmatically at runtime as I'm doing.

Unity 2D Tilemap Custom Hexagonal Rule Tile

1 Answers