How to Get Coordinates from Hex Map on Click in Unity

Question

I'm making the board game known as Hex. When I click on a tile, it changes to either blue or yellow, but I need to also be able to know what the coordinates of that tile are.

I can't use...

rend.transform.position;

...because the the coordinates I want to receive look similar to this (0,0) being the bottom left and (0,1) above it:

The coordinates in the console are the one's I need to receive.

I printed those out by using the column and row variables when I generated the hex map:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;

public class HexMap : MonoBehaviour
{
 // Use this for initialization
 void Start()
 {
    GenerateMap();
 }

public GameObject HexPrefab;

public void GenerateMap()
{
    for (int column = 0; column < 11; column++)
    {
        for (int row = 0; row < 11; row++)
        {
            // Instantiate a Hex
            Hex h = new Hex(column, row);

            Instantiate(HexPrefab, h.Position(), Quaternion.identity, this.transform);

            Debug.Log(column + "," + row);
        }
    }
}
}

I want to be able to get the coordinates when I click a hex tile using this script here:

using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Net;
using UnityEngine;
using UnityEngine.Networking;

public class ColorChange : MonoBehaviour {

public Color[]colors; // allows input of material colors in a set sized array
public SpriteRenderer rend;  // what are we rendering? the hex

public enum Player {ONE, TWO};
public static Player currentPlayer = Player.ONE;

// Use this for initialization
void Start () {
    rend = GetComponent<SpriteRenderer> (); // gives functionality for the renderer
}

void NextPlayer() {

   if( currentPlayer == Player.ONE ) {
      currentPlayer = Player.TWO;
   }
   else if( currentPlayer == Player.TWO) {
      currentPlayer = Player.ONE;
   }
}

// Update is called once per frame
void OnMouseDown () {
    // if there are no colors present nothing happens
    if (colors.Length == 0)
        return;

    if (currentPlayer == Player.ONE)
        rend.color = colors [0];
    else if (currentPlayer == Player.TWO)
        rend.color = colors [1];

    NextPlayer();
}

Here is the script I use to determine where the hex tiles need to be:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Hex{

public Hex (int q, int r){
    this.Q = q;
    this.R = r;
}

public readonly int Q; // x
public readonly int R;  // y

static readonly float WIDTH_MULTIPLIER = Mathf.Sqrt(3) / 2;

public Vector2 Position(){
    float radius = 0.513f;
    float height = radius * 2;
    float width = WIDTH_MULTIPLIER * height;

    float vert = height * 0.75f;
    float horiz = width;

    return new Vector2(horiz * (this.Q - this.R/2f), vert * this.R);
}
}

I was thinking I need to be able to assign each Hex Model the value of column and row when it is instantiated, but I'm not sure how to do that. I tried several solutions I found online as well as using GetComponent, but I wasn't able to make them work. If anyone has an idea on how this might be possible I would greatly appreciate it!

you may want to read that https://catlikecoding.com/unity/tutorials/hex-map/part-1/ — yes, Apr 25 '19 at 16:50

score 1 · Accepted Answer · answered Apr 25 '19 at 11:33

The reason why GetComponent is not working in your case is because the Coordinates script is on a child object of the hex prefab. You could access a component on a child object by calling GetComponentInChildren. It would look something like the following:

// Instantiate a Hex
Hex h = new Hex(column, row);

// Instantiate the prefab
GameObject instance = Instantiate(HexPrefab, h.Position(), Quaternion.identity, this.transform);

// Let's find the coorinates component on the hex prefab instance.
Coordinates coordinates = instance.GetComponentInChildren<Coordinates>();

// now you may assign the column and row values to it
// ...

There are many possible approaches to this problem. But just keep in mind where in the prefab hierarchy the components are and you will be fine.

Thank you, this worked! Do you know how I would be able use those coordinates to find the corresponding hex GameObject? Because after sending those coordinates to the server, I'm going to receive another pair of coordinates for the move the AI makes and I need to mark on the board where those coordinates are. — Jon, Apr 29 '19 at 21:54

How to Get Coordinates from Hex Map on Click in Unity

1 Answers1