/// <summary>
/// 查找point是否在节点列表里面
/// </summary>
/// <param name="nodeList">节点列表</param>
/// <param name="point">用于查找的节点</param>
/// <param name="pIndex">返回节点索引</param>
/// <returns>if inside,return sucess,else return not inside</returns>
public static PolyResCode NavNodeGetNodeIndex(List <NavNode> nodeList, Vector2 point, out int pIndex)
{
pIndex = -1;
for (int i = 0; i < nodeList.Count; i++)
{
NavNode node = nodeList[i];
if (NMath.Equals(node.vertex, point))
{
pIndex = i;
return(PolyResCode.Success);
}
}
return(PolyResCode.ErrNotInside);
}
/// <summary>
/// 合并两个节点列表，生成交点，并按顺时针序插入到顶点表中
/// </summary>
/// <param name="c0">主多边形顶点表，并返回插入交点后的顶点表</param>
/// <param name="c1">合并多边形顶点表，并返回插入交点后的顶点表</param>
/// <param name="nInsCnt">交点个数</param>
/// <returns></returns>
public static PolyResCode NavNodeIntersectPoint(List<NavNode> c0, List<NavNode> c1, out int nInsCnt)
{
nInsCnt = 0;
NavNode startNode0 = c0[0];
NavNode startNode1 = null;
Line2D line0, line1;
Vector2 insPoint;
bool hasIns = false;
while (startNode0 != null)
{
// 判断是否到末点了
if (startNode0.next == null)
line0 = new Line2D(startNode0.vertex, c0[0].vertex);
else
line0 = new Line2D(startNode0.vertex, startNode0.next.vertex);
startNode1 = c1[0];
hasIns = false;
while (startNode1 != null)
{
if (startNode1.next == null)
line1 = new Line2D(startNode1.vertex, c1[0].vertex);
else
line1 = new Line2D(startNode1.vertex, startNode1.next.vertex);
if (line0.Intersection(line1, out insPoint) == LineCrossState.CROSS)
{
int insPotIndex = -1;
//如果交点不在多边形的节点上
if (NavUtil.NavNodeGetNodeIndex(c0, insPoint, out insPotIndex) == PolyResCode.ErrNotInside)
{
nInsCnt++;
NavNode node0 = new NavNode(insPoint, true, true);
NavNode node1 = new NavNode(insPoint, true, false);
c0.Add(node0);
c1.Add(node1);
node0.other = node1;
node1.other = node0;
//插入顶点列表
node0.next = startNode0.next;
startNode0.next = node0;
node1.next = startNode1.next;
startNode1.next = node1;
if (line0.ClassifyPoint(line1.GetEndPoint()) == PointSide.RIGHT_SIDE)
{
node0.o = true;
node1.o = true;
}
hasIns = true;
break;
}
}
startNode1 = startNode1.next;
}
if (!hasIns)
startNode0 = startNode0.next;
}
return PolyResCode.Success;
}
// ========================================== 合并 ============================================= //
/// <summary>
/// 合并两个交叉的多边形(多边形必须先转换为顺时针方向，调用CW()函数!)
/// </summary>
/// <param name="other"></param>
/// <param name="polyRes"></param>
/// <returns></returns>
public PolyResCode Union(Polygon other, ref List<Polygon> polyRes)
{
if (this.m_lstPoints.Count == 0 || other.m_lstPoints.Count == 0)
return PolyResCode.ErrEmpty;
else if (!NMath.CheckCross(GetCoverRect(), other.GetCoverRect()))
return PolyResCode.ErrNotCross;
// 转换为顺时针方向
//this.CW();
//other.CW();
List<NavNode> mainNode = new List<NavNode>(); //主多边形顶点
List<NavNode> subNode = new List<NavNode>(); //需要合并的多边形顶点
// init main nodes
for (int i = 0; i < this.m_lstPoints.Count; i++)
{
NavNode currNode = new NavNode(this.m_lstPoints[i], false, true);
if (i > 0)
{
NavNode preNode = mainNode[i - 1];
preNode.next = currNode;
}
mainNode.Add(currNode);
}
// init sub nodes
for (int j = 0; j < other.m_lstPoints.Count; j++)
{
NavNode currNode = new NavNode(other.m_lstPoints[j], false, false);
if (j > 0)
{
NavNode preNode = subNode[j - 1];
preNode.next = currNode;
}
subNode.Add(currNode);
}
int insCnt = 0;
PolyResCode result = NavUtil.NavNodeIntersectPoint(mainNode, subNode, out insCnt);
if (result == PolyResCode.Success && insCnt > 0)
{
if (insCnt % 2 != 0)
{
return PolyResCode.ErrCrossNum;
}
else
{
PolyResCode linkRes = NavUtil.LinkToPolygon(mainNode, subNode, ref polyRes);
return linkRes;
}
}
return PolyResCode.ErrCrossNum;
}
/// <summary>
/// 合并两个节点列表，生成交点，并按顺时针序插入到顶点表中
/// </summary>
/// <param name="c0">主多边形顶点表，并返回插入交点后的顶点表</param>
/// <param name="c1">合并多边形顶点表，并返回插入交点后的顶点表</param>
/// <param name="nInsCnt">交点个数</param>
/// <returns></returns>
public static PolyResCode NavNodeIntersectPoint(List <NavNode> c0, List <NavNode> c1, out int nInsCnt)
{
nInsCnt = 0;
NavNode startNode0 = c0[0];
NavNode startNode1 = null;
Line2D line0, line1;
Vector2 insPoint;
bool hasIns = false;
while (startNode0 != null)
{
// 判断是否到末点了
if (startNode0.next == null)
{
line0 = new Line2D(startNode0.vertex, c0[0].vertex);
}
else
{
line0 = new Line2D(startNode0.vertex, startNode0.next.vertex);
}
startNode1 = c1[0];
hasIns = false;
while (startNode1 != null)
{
if (startNode1.next == null)
{
line1 = new Line2D(startNode1.vertex, c1[0].vertex);
}
else
{
line1 = new Line2D(startNode1.vertex, startNode1.next.vertex);
}
if (line0.Intersection(line1, out insPoint) == LineCrossState.CROSS)
{
int insPotIndex = -1;
//如果交点不在多边形的节点上
if (NavUtil.NavNodeGetNodeIndex(c0, insPoint, out insPotIndex) == PolyResCode.ErrNotInside)
{
nInsCnt++;
NavNode node0 = new NavNode(insPoint, true, true);
NavNode node1 = new NavNode(insPoint, true, false);
c0.Add(node0);
c1.Add(node1);
node0.other = node1;
node1.other = node0;
//插入顶点列表
node0.next = startNode0.next;
startNode0.next = node0;
node1.next = startNode1.next;
startNode1.next = node1;
if (line0.ClassifyPoint(line1.GetEndPoint()) == PointSide.RIGHT_SIDE)
{
node0.o = true;
node1.o = true;
}
hasIns = true;
break;
}
}
startNode1 = startNode1.next;
}
if (!hasIns)
{
startNode0 = startNode0.next;
}
}
return(PolyResCode.Success);
}
/// <summary>
/// 合并两个节点列表为一个多边形，结果为顺时针序( 生成的内部孔洞多边形为逆时针序)
/// </summary>
/// <param name="mainNode"></param>
/// <param name="subNode"></param>
/// <param name="polyRes"></param>
/// <returns></returns>
public static PolyResCode LinkToPolygon(List <NavNode> mainNode, List <NavNode> subNode, ref List <Polygon> polyRes)
{
polyRes.Clear();
for (int i = 0; i < mainNode.Count; i++)
{
NavNode currNode = mainNode[i];
// 选择一个没有访问过的交点做起始点
if (currNode.isIns && !currNode.passed)
{
List <Vector2> points = new List <Vector2>();
while (currNode != null)
{
currNode.passed = true;
//交点转换
if (currNode.isIns)
{
currNode.other.passed = true;
if (!currNode.o) //该交点为进点（跟踪裁剪多边形边界）
{
if (currNode.isMain) //当前点在主多边形中
{
currNode = currNode.other; //切换到裁剪多边形中
}
}
else
{
//该交点为出点（跟踪主多边形边界）
if (!currNode.isMain) //当前点在裁剪多边形中
{
currNode = currNode.other; //切换到主多边形中
}
}
}
points.Add(currNode.vertex);
if (currNode.next == null)
{
if (currNode.isMain)
{
currNode = mainNode[0];
}
else
{
currNode = subNode[0];
}
}
else
{
currNode = currNode.next;
}
if (currNode.vertex == points[0])
{
break;
}
}
// 删除重复顶点
Polygon poly = new Polygon(points);
poly.DelRepeatPoint();
polyRes.Add(poly);
}
}
return(PolyResCode.Success);
}