IsometricMapEditor.cs

using UnityEngine;
using UnityEditor;

[CustomEditor(typeof(IsometricMap))]
public class IsometricMapEditor : Editor {
  private IsometricMap map;
  
  void OnEnable() {
      map = (IsometricMap) target;
  }
  
  void OnSceneGUI(){
    Event e = Event.current;
    Ray r = HandleUtility.GUIPointToWorldRay(new Vector2(e.mousePosition.x, e.mousePosition.y));
    Vector3 mousePosition= r.origin;
    
    if (e.isMouse) {
      Tools.current = Tool.View;
      Tools.viewTool = ViewTool.FPS;
      SceneView.RepaintAll();
    }

    Texture2D pattern = map.pattern;
    int pixelToUnit = map.pixelToUnit;
    Vector2 pixelSize = map.pixelSize;
    
    Vector2 tileSize = new Vector2(pixelSize .x / pixelToUnit, (pixelSize .y * .5f) / pixelToUnit);
    Vector2 tilePosition = new Vector2((int)(mousePosition.x / tileSize .x), (int)(mousePosition.y / tileSize .y));
    
    Vector2 realPosition = new Vector2(tilePosition .x * tileSize .x, tilePosition .y * tileSize .y);
    Vector2 markerPosition = new Vector2(realPosition .x + tileSize .x / 2, realPosition .y + tileSize .y / 2);

    int localPointX = (int)((mousePosition.x % tileSize .x) * pixelToUnit);
    int localPointY = (int)((mousePosition.y % tileSize .y) * pixelToUnit);

    Color pixelColor = pattern.GetPixel(localPointX, localPointY);

    if (pixelColor == Color.red){
      //Seleciona o tile que está na parte de cima do lado esquerdo
      markerPosition = new Vector2(markerPosition .x — tileSize .x / 2, markerPosition .y + tileSize .y / 2);
    } else if(pixelColor == Color.green){
      //Seleciona o tile que está na parte de baixo do lado esquerdo
      markerPosition = new Vector2(markerPosition .x — tileSize .x / 2, markerPosition .y — tileSize .y / 2);
    } else if(pixelColor == Color.yellow){
      //Seleciona o tile que está na parte de cima do lado direito
      markerPosition = new Vector2(markerPosition .x + tileSize .x / 2, markerPosition .y + tileSize .y / 2);
    } else if(pixelColor == Color.blue){
      //Seleciona o tile que está na parte de baixo do lado direito
      markerPosition = new Vector2(markerPosition .x + tileSize .x / 2, markerPosition .y — tileSize .y / 2);
    } else {
      //Está no tile atual
    }

    map.markerPosition = markerPosition;
    if (e.type == EventType.MouseDown && e.button == 0 || e.type == EventType.MouseDrag && e.button == 0) {
      //Desenha tile selecionado.
      e.Use();
    }

    if (e.type == EventType.MouseDown && e.button == 1 || e.type == EventType.MouseDrag && e.button == 1) {
      //Deleta Tile selecionado
      e.Use();
    }
  }
}