// data是否在多个象限内
// 多象限内，放到父节点上
private bool isInMultipleSub(QuadNode node, QuadData data)
{
int cnt = 0;
if (null == node.Sub)
{
split(node);
}
for (int i = 0; i < 4; ++i)
{
if (isRegionCross(node.Sub[i].mbr, data.mbr))
{
cnt++;
}
}
if (0 == cnt) // 大于整个象限了
{
return(true);
}
else
if (cnt > 1) // 处于多个象限
{
return(true);
}
else
{
return(false);
}
}
// 删除
// 从四叉树中移除,调用时需要data数据修改前调用，如果data数据修改后调用，可能无法找到。
// 导致数据错误
public bool Remove(QuadData data)
{
var tmp = _root;
bool rm = false;
bool success = false;
// 没有节点
do
{
// 节点数 满足，或者处于多个象限中
if ((tmp.Cnt <= MAX_DATA_CNT && null == tmp.Sub) || isInMultipleSub(tmp, data))
{
// 跳出循环
rm = true;
// 重复删除同一个数据
if (null == tmp.Child)
{
break;
}
// 本节点查找
var curNode = tmp.Child;
var preNode = tmp.Child;
do
{
if (curNode == data)
{
// 头
if (curNode == tmp.Child)
{
tmp.Child = curNode.Next;
}
else
{
preNode.Next = curNode.Next;
}
success = true;
tmp.Cnt--;
TotalCnt--;
LevelCnt[tmp.Level]--;
break;
}
preNode = curNode;
curNode = curNode.Next;
} while (null != curNode);
}
else
{
// 获取所在象限
tmp = GetSubNode(tmp, data);
}
} while (false == rm);
return(success);
}
// 更新
// 跟新data在四叉树中的位置
public bool Update(QuadData data, QuadData newData)
{
bool success = Remove(data);
if (false == success)
{
// 失败了，逻辑错误
log($"error remove data. {data.Id}");
return(false);
}
Add(newData);
return(true);
}
public QuadNode GetSubNode(QuadNode node, QuadData data)
{
QuadNode sub = null;
for (int i = 0; i < MAX_QUADRANT; ++i)
{
if (false == isRegionCross(node.Sub[i].mbr, data.mbr))
{
continue;
}
sub = node.Sub[i];
break;
}
return(sub);
}
// 添加
public bool Add(QuadData data)
{
// 节点node数量判定
// 寻找符合节点插入
bool success = false;
QuadNode tmp = _root;
do
{
bool addToParentNode = false;
// 当前节点child个数小于最大child个数,并且没有分裂过
if (tmp.Cnt + 1 <= MAX_DATA_CNT && null == tmp.Sub)
{
addToParentNode = true;
}
// 节点个数<MAX_DATA_CNT && 为分裂的
// 多象限内直接插入本节点
if (addToParentNode || isInMultipleSub(tmp, data))
{
// 加入本节点
var n1 = tmp.Child;
tmp.Child = data;
data.Next = n1;
tmp.Cnt++;
TotalCnt++;
addLevelCnt(tmp.Level);
success = true;
// 跳出
break;
}
else
{
split(tmp);
// 获取插入的指定象限，
tmp = GetSubNode(tmp, data);
}
}while (true);
return(success);
}
static void Main(string[] args)
{
QuadTree tree = new QuadTree();
Random ran = new Random((int)DateTime.Now.Ticks);
// 长宽2000
int hl = 1000;
tree.Init(new MBR(-hl, hl, hl, -hl));
var qd1 = (new QuadData()
{
Id = 1,
mbr = new MBR(1, 20, 30, 1),
Next = null,
});
var qd2 = (new QuadData()
{
Id = 2,
mbr = new MBR(-30, -1, 10, 1),
Next = null,
});
var qd3 = new QuadData()
{
Id = 3,
mbr = new MBR(-30, -1, -1, -10),
Next = null,
};
var qd4 = new QuadData()
{
Id = 4,
mbr = new MBR(1, 20, -1, -40),
Next = null,
};
// 1,2,3,4象限个插入一个
tree.Add(qd1);
tree.Add(qd2);
tree.Add(qd3);
tree.Add(qd4);
// 随机插入100个
int insertCnt = 1000000;
float x, z;
int minwidth = 1, maxwidth = 10, minlen = 1, maxlen = 60;
List <QuadData> rmList = new List <QuadData>();
QuadData randomSelect = null;
int randomSelectIndex = ran.Next(0, insertCnt);
for (int i = 0; i < insertCnt; ++i)
{
var qd = new QuadData();
qd.Id = i;
float l, r, t, b;
// 坐标
x = ran.Next(-hl, hl);
z = ran.Next(-hl, hl);
//
float hwidth = ran.Next(minwidth, maxwidth);
float hlen = ran.Next(minlen, maxlen);
//
l = x - hwidth;
r = x + hwidth;
t = z + hlen;
b = z - hlen;
qd.mbr = new MBR(l, r, t, b);
qd.Next = null;
tree.Add(qd);
rmList.Add(qd);
if (i == randomSelectIndex)
{
randomSelect = qd;
}
}
string info = "";
foreach (var levelData in tree.LevelCnt)
{
info += $"({levelData.Key}:{levelData.Value})-";
}
Console.WriteLine($"tree level:{tree.Current_Max_Level} {info}");
//
var circle = new Circle()
{
x = 30,
z = 30,
radius = 30,
};
var circle1 = new Circle()
{
x = 0,
z = 0,
radius = 500,
};
Stopwatch sw = new Stopwatch();
// 每秒一次搜索, 这些单位平均一秒执行搜索次数
double ms = 0;
find(sw, tree, circle, insertCnt);
find(sw, tree, circle1, insertCnt);
sw.Restart();
int rmCnt = 0;
bool rm = tree.Remove(qd1);
if (rm)
{
rmCnt++;
}
ms = sw.Elapsed.TotalMilliseconds;
//for (int i = 0; i < rmList.Count; ++i)
//{
// rm = tree.Remove(rmList[i]);
// if (rm)
// rmCnt++;
// if (false == rm)
// Console.WriteLine($"rm rmList[i] {rmList[i].Id} not success");
//}
Console.WriteLine($"remove qd1 ms={ms} rm:{rm} rmCnt:{rmCnt}");
sw.Restart();
rm = tree.Remove(randomSelect);
ms = sw.Elapsed.TotalMilliseconds;
Console.WriteLine($"remove randomSelect index={randomSelectIndex} ms={ms} rm:{rm} rmCnt:{rmCnt}");
sw.Restart();
tree.Remove(qd2);
tree.Clear();
tree.Remove(qd3);
ms = sw.Elapsed.TotalMilliseconds;
Console.WriteLine($"clear ms={ms}");
Console.WriteLine("Hello World!");
}
