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

/// <summary>
/// 地图坐标转换工具
/// </summary>
public static class MapHelper 
{
    static bool hasInit;
    static Vector2 terrainSize;
    static Vector2 mapSize;
    /// <summary>
    /// 地形/地图的
    /// </summary>
    public static float mapScale;

    //static Vector2 
    public static void InitHelper(Vector2 terrainSize,Vector2 mapSize)
    {
        hasInit = true;
        MapHelper.terrainSize = terrainSize;
        MapHelper.mapSize = mapSize;
        mapScale = terrainSize.x / mapSize.x;
    }

    public static Vector3 GetWorldPosFromAnchPos(Vector2 anchoredPos)
    {
        if (!hasInit)
        {
            Debug.LogError("未初始化地图数据无法转换");
            return Vector3.zero;
        }
        Vector3 worldPos = new Vector3(anchoredPos.x + mapSize.x / 2, 0, anchoredPos.y + mapSize.x / 2) * mapScale;
        worldPos.y = Terrain.activeTerrain.SampleHeight(worldPos);//获取与地形对应点的世界坐标高度3
        return worldPos;
    }


    // <summary>
    /// 根据世界坐标获取地图锚点坐标    地形必须是正方形  长方形需修改该方法
    /// </summary>
    /// <param name="worldPos"></param>
    /// <returns> 返回以地图中心为锚点的锚点位置</returns>
    public static Vector2 GetAnchorPostionFromWorld(Vector3 worldPos)
    {
        if (!hasInit)
        {
            Debug.LogError("未初始化地图数据无法转换");
            return Vector2.zero;
        }

        return new Vector2(worldPos.x - terrainSize.x / 2, worldPos.z - terrainSize.y / 2) / mapScale;
    }

    /// <summary>
    /// 计算物体尺寸在地图上的像素点
    /// </summary>
    /// <param name="size">单位M</param>
    /// <returns>像素点</returns>
    public static float GetPixelFromSize(float size)
    {
        if (!hasInit)
        {
            Debug.LogError("未初始化地图数据无法转换");
            return 0;
        }
        return  size/ mapScale;
    }



    public static void Clear()
    {
        hasInit = false;
    }

}