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);
}
// 初始化四叉树范围
public void Init(MBR mbr)
{
if (null != _root)
{
return;
}
_root = new QuadNode();
_root.mbr = mbr;
_root.Quadrant = EQuadrant.ROOT;
_root.Level = 0;
// debug
LevelCnt = new Dictionary <int, int>();
TotalCnt = 0;
CorssCircleTestCnt = 0;
// debug
}
// 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);
}
private void ForeachNode(QuadNode node, List <QuadData> lst)
{
if (null == node)
{
return;
}
if (null == lst)
{
return;
}
Queue <QuadNode> nodes = new Queue <QuadNode>();
nodes.Enqueue(node);
var tmp = node;
do
{
tmp = nodes.Dequeue();
var n1 = tmp.Child;
while (null != n1)
{
lst.Add(n1);
n1 = n1.Next;
}
if (null != tmp.Sub)
{
for (int i = 0; i < MAX_QUADRANT; ++i)
{
nodes.Enqueue(tmp.Sub[i]);
}
}
} while (nodes.Count > 0);
}
// 象限分裂
// 分裂后，node节点的数据，尝试插入到子象限内
private void split(QuadNode node)
{
// 已经分裂过了
if (null != node.Sub)
{
return;
}
// 分裂为四个象限
/*
|
|
| UL | UR
| ---------------------
|
| LL | LR
|
|
*/
// mbr = (x,z,w,l)
var mbr = node.mbr;
float hw = (mbr.right - mbr.left) * 0.5f;
float hl = (mbr.top - mbr.bottom) * 0.5f;
var mbr_ur = new MBR(mbr.right - hw, mbr.right, mbr.top, mbr.top - hl);
var mbr_ul = new MBR(mbr.left, mbr.left + hw, mbr.top, mbr.top - hl);
var mbr_ll = new MBR(mbr.left, mbr.left + hw, mbr.bottom + hl, mbr.bottom);
var mbr_lr = new MBR(mbr.right - hw, mbr.right, mbr.bottom + hl, mbr.bottom);
node.Sub = new QuadNode[4];
node.Sub[0] = new QuadNode()
{
Level = node.Level + 1, Quadrant = EQuadrant.UR, Cnt = 0, mbr = mbr_ur, Child = null, Sub = null,
};
node.Sub[1] = new QuadNode()
{
Level = node.Level + 1, Quadrant = EQuadrant.UL, Cnt = 0, mbr = mbr_ul, Child = null, Sub = null,
};
node.Sub[2] = new QuadNode()
{
Level = node.Level + 1, Quadrant = EQuadrant.LL, Cnt = 0, mbr = mbr_ll, Child = null, Sub = null,
};
node.Sub[3] = new QuadNode()
{
Level = node.Level + 1, Quadrant = EQuadrant.LR, Cnt = 0, mbr = mbr_lr, Child = null, Sub = null,
};
if (node.Level + 1 > Current_Max_Level)
{
Current_Max_Level = node.Level + 1;
}
// 尝试插入当前节点的child
TotalCnt -= node.Cnt;
LevelCnt[node.Level] -= node.Cnt;
node.Cnt = 0;
if (node.Child != null)
{
var tmp = node.Child;
var tmp1 = tmp.Next;
node.Child = null;
while (null != tmp)
{
Add(tmp);
tmp = tmp1;
if (null != tmp)
{
tmp1 = tmp.Next;
tmp.Next = null;
}
}
}
}