unity四叉树

public class QuadTree_1
{
    //节点内允许的最大对象
    private int maxObjs = 1;

    //最大层级
    private int maxLvl = 3;

    //当前层级
    private int lvl;

    //当前层级内的对象
    private List<Transform> transList;

    //rect范围
    private Vector3 minPos;

    private Vector3 maxPos;

    private Vector2 dis;
    //子节点
    private List<QuadTree_1> childs;

    private QuadTree_1 parent;
    
    private List<Color> color = new List<Color>() {Color.cyan, Color.blue, Color.green, Color.red, Color.yellow, Color.gray};
    
    public QuadTree_1(Vector3 minPos, Vector3 maxPos, QuadTree_1 parent, int lvl, int maxObjs, int maxLvl)
    {
        this.minPos = minPos;
        this.maxPos = maxPos;
        dis = new Vector2(maxPos.x - minPos.x, maxPos.z - minPos.z);
        this.parent = parent;
        this.lvl = lvl;
        this.maxObjs = maxObjs;
        this.maxLvl = maxLvl;
        transList = new List<Transform>();
        childs = new List<QuadTree_1>(4);
    }

    public void Insert(Transform trans)
    {
        //直接往下找 递归下去
        if (childs.Count != 0 && lvl < maxLvl)
        {
            for (int j = 0; j < childs.Count; j++)
            {
                if (childs[j].CheckArea(trans.position))
                {
                    childs[j].Insert(trans);
                    return;
                }
            }
            //处理临界状态
            transList.Add(trans);
            return;
        }

        transList.Add(trans);
        // Debug.Log($"当前等级{lvl}   最大等级{maxLvl}");
        if (transList.Count > maxObjs && lvl < maxLvl)
        {
            if (childs.Count == 0)
            {
                Vector3 midPos = (maxPos + minPos) / 2;
                Vector3 disL = new Vector3(dis.x / 2, 0, 0);
                childs.Add(new QuadTree_1(midPos, maxPos, this, lvl + 1, maxObjs, maxLvl));
                childs.Add(new QuadTree_1(midPos - disL, maxPos - disL, this, lvl + 1, maxObjs, maxLvl));
                childs.Add(new QuadTree_1(minPos, midPos, this, lvl + 1, maxObjs, maxLvl));
                childs.Add(new QuadTree_1(minPos + disL, midPos + disL, this, lvl + 1, maxObjs, maxLvl));
            }
            
            for (int i = transList.Count - 1; i >= 0; i--)
            {
                for (int j = 0; j < childs.Count; j++)
                {
                    if (childs[j].CheckArea(transList[i].position))
                    {
                        childs[j].Insert(transList[i]);
                        transList.Remove(transList[i]);
                        break;
                    }
                }
            }
        }
    }

    public List<Transform> FindRoundPoint()
    {
        List<Transform> list = new List<Transform>();
        if (parent == null)
        {
            FindRoundPoint(ref list); 
        }
        else
        {
            parent.FindRoundPoint(ref list); 
        }
        
        return list;
    }


    private void FindRoundPoint(ref List<Transform> list)
    {
        for (int i = 0; i < transList.Count; i++)
        {
            list.Add(transList[i]);
        }

        for (int i = 0; i < childs.Count; i++)
        {
            childs[i].FindRoundPoint(ref list);
        }
    }
    

    //根据区域进行递归查找会更快一些
    public QuadTree_1 FindQuadTree(Transform target)
    {
        if (transList.Contains(target))
        {
            return this;
        }

        for (int i = 0; i < childs.Count; i++)
        {
            if (childs[i].CheckArea(target.position))
            {
                return childs[i].FindQuadTree(target);
            }
        }

        return null;
    }

    private bool CheckArea(Vector3 pos)
    {
        return pos.x > minPos.x && pos.z > minPos.z && pos.x < maxPos.x && pos.z < maxPos.z;
    }

    public void Clear()
    {
        transList.Clear();
        parent = null;
        for (int i = 0; i < childs.Count; i++)
        {
            childs[i].Clear();
        }
        childs.Clear();
    }

    public void Draw()
    {
        Vector3 rb = minPos + new Vector3(dis.x, 0, 0);
        Vector3 lt = maxPos - new Vector3(dis.x, 0, 0);
        Debug.DrawLine(minPos, rb, color[lvl]);
        Debug.DrawLine(rb, maxPos, color[lvl]);
        Debug.DrawLine(maxPos, lt, color[lvl]);
        Debug.DrawLine(lt, minPos, color[lvl]);
        // for (int i = 0; i < transList.Count; i++)
        // {
        //     transList[i].GetComponent<MeshRenderer>().material.color = color[lvl];
        // }
        for (int i = 0; i < childs.Count; i++)
        {
            childs[i].Draw();
        }
    }
}