#include "stdafx.h"
#include "topologicalanalysis.h"


TopologicalAnalysis::TopologicalAnalysis(void)
{
}


TopologicalAnalysis::~TopologicalAnalysis(void)
{
}


bool TopologicalAnalysis::isPointInLine(double* point, double* startPoint, double* endPoint,float tolerance)
{
	double AX = startPoint[0];
	double AY = startPoint[1];
	double BX = endPoint[0];
	double BY = endPoint[1];
	double PX = point[0];
	double PY = point[1];

	double dx_AB = AX - BX;
	double dy_AB = AY - BY;
	double dx_PA = PX - AX;
	double dy_PA = PY - AY;
	double dx_PB = PX - BX;
	double dy_PB = PY - BY;

	double AB = sqrt(dx_AB*dx_AB + dy_AB*dy_AB);
	double PA = sqrt(dx_PA*dx_PA + dy_PA*dy_PA);
	double PB = sqrt(dx_PB*dx_PB + dy_PB*dy_PB);
	double rate = abs(PA + PB - AB) / AB;
	if (rate < tolerance)
	{
		return true;
	}
	else
	{
		return false;
	}
}

//判断线是否在折线上
int TopologicalAnalysis::isPointInPolyLine(double* point, vector<double>& lineX,vector<double>& lineY,float tolerance)
{
	int lineNum = lineX.size();
	double startPoint[2],endPoint[2];
	for (int i=0;i<lineNum-1;i++)
	{
		startPoint[0] = lineX.at(i);
		startPoint[1] = lineY.at(i);
		endPoint[0] = lineX.at(i+1);
		endPoint[1] = lineY.at(i+1);
		bool b_in = isPointInLine(point,startPoint,endPoint,tolerance);
		if(b_in)
		{
			return (i+1);
		}
	}
	//判断收尾点线段
	startPoint[0] = lineX.at(lineNum-1);
	startPoint[1] = lineY.at(lineNum-1);
	endPoint[0] = lineX.at(0);
	endPoint[1] = lineY.at(0);
	bool b_end = isPointInLine(point,startPoint,endPoint,tolerance);
	if (b_end)
	{
		return lineNum;
	}
	else
	{
		return 0;
	}
}

//根据两点求出垂线过第三点的直线的交点
bool TopologicalAnalysis::GetPointToLineVerticalCross(double* linePt1,double* linePt2,double* pt,double* crossPt)
{
	//垂直线
	if (linePt1[0] == linePt2[0])
	{
		crossPt[0] = linePt1[0];
		crossPt[1] = pt[1];
		return true;
	}
	//水平线
	if (linePt1[1] == linePt2[1])
	{
		crossPt[0] = pt[0];
		crossPt[1] = linePt1[1];
		return true;
	}
	float A = (linePt1[1]- linePt2[1]) * 1.0 / (linePt1[0]- linePt2[0]);
	float B = (linePt1[1] - A * linePt1[0]);
	float m = pt[0] + A * pt[1];

	/// 求两直线交点坐标
	crossPt[0] = (m - A * B) * 1.0f / (A * A + 1);
	crossPt[1] = A * crossPt[0] + B;
	return true;
}

//判断点是否在(简单)多边形内
//polygon: 首尾相同的Cpoint1列表
bool TopologicalAnalysis::isPointInPolygon(CPoint1 point, vector<CPoint1> polygon){
	if (polygon.size()<=3) return false;	// 一个有效多边形顶点数应大于3

	int LineNum = polygon.size();
	CPoint1 leftP = point;
	CPoint1 rightP;
	rightP.SetX(getMaxX(polygon) + 1);
	rightP.SetY(point.GetY());
	int count = 0, yPrev = polygon[LineNum - 2].GetY();
	CPoint1 v1, v2;
	v1 = polygon[LineNum - 1];
	for (int i = 0; i < LineNum; i++)
	{
		v2 = polygon[i];

		if (isPointInLine(leftP, v1, v2))
			return true;

		if (v1.GetY() != v2.GetY())
		{
			if (isLineIntersect(v1, v2, leftP, rightP))
			{
				if (isPointInLine(v1, leftP, rightP))
				{
					if (v1.GetY()<v2.GetY()) { if (v1.GetY()>yPrev)  count++; }
					else { if (v1.GetY() < yPrev) count++; }
				}
				else if (!isPointInLine(v2, leftP, rightP))
				{
					count++;
				}
			}
		}
		yPrev = v1.GetY();

		v1 = v2;
	}
	return   (count % 2 == 1);
}

double TopologicalAnalysis::getMaxX(vector<CPoint1> points){
	if (points.size()==0)
		return -1;
	else if(points.size()==1)
		return points[0].GetX();
	else{
		double maxx = points[0].GetX();
		for (unsigned i=1; i<points.size();i++)
		{
			if(points[i].GetX()>maxx){
				maxx = points[i].GetX();
			}
		}
		return maxx;
	}
}

bool  TopologicalAnalysis::isPointInLine(CPoint1 point, CPoint1 startPoint, CPoint1 endPoint)
{
	long AX = startPoint.GetX();
	long AY = startPoint.GetY();
	long BX = endPoint.GetX();
	long BY = endPoint.GetY();
	long PX = point.GetX();
	long PY = point.GetY();

	double dx_AB = AX - BX;
	double dy_AB = AY - BY;
	double dx_PA = PX - AX;
	double dy_PA = PY - AY;
	double dx_PB = PX - BX;
	double dy_PB = PY - BY;

	double AB = sqrt(dx_AB*dx_AB + dy_AB*dy_AB);
	double PA = sqrt(dx_PA*dx_PA + dy_PA*dy_PA);
	double PB = sqrt(dx_PB*dx_PB + dy_PB*dy_PB);
	double rate = abs(PA + PB - AB) / AB;
	if (rate < 0.001)
	{
		return true;
	}
	else
	{
		return false;
	}
}
// 叉积
double mult(CPoint1 a, CPoint1 b, CPoint1 c)  
{  
	return (a.GetX()-c.GetX())*(b.GetY()-c.GetY())-(b.GetX()-c.GetX())*(a.GetY()-c.GetY());  
}

//判断两条直线段是否相交
bool TopologicalAnalysis::isLineIntersect(CPoint1 line1Start, CPoint1 line1End, CPoint1 line2Start, CPoint1 line2End){
	double l1sx = line1Start.GetX();
	double l1sy = line1Start.GetY();
	double l1ex = line1End.GetX();
	double l1ey = line1End.GetY();
	double l2sx = line2Start.GetX();
	double l2sy = line2Start.GetY();
	double l2ex = line2End.GetX(); 
	double l2ey = line2End.GetY();
	if ( max(l1sx, l1ex)<min(l2sx, l2ex) )  
	{  
		return false;  
	}  
	if ( max(l1sy, l1ey)<min(l2sy,l2ey) )  
	{  
		return false;  
	}  
	if ( max(l2sx, l2ex)<min(l1sx, l1ex) )  
	{  
		return false;  
	}  
	if ( max(l2sy,l2ey)<min(l1sy, l1ey) )  
	{  
		return false;  
	}  
	if ( mult(line2Start, line1End, line1Start)*mult(line1End, line2End, line1Start)<0 )  
	{  
		return false;  
	}  
	if ( mult(line1Start, line2End, line2Start)*mult(line2End, line1End, line2Start)<0 )  
	{  
		return false;  
	}  
	return true;  
}


bool TopologicalAnalysis::GetBoundingBoxVertices(const vector<double>& polygonX,const vector<double>& polygonY,vector<double>& rectangleX,vector<double>& rectangleY)
{
	if (polygonX.size()<3 || polygonY.size()<3) return false;

	//计算最大最小x和y
	double minX = polygonX[0];
	double minY = polygonY[0];
	double maxX = polygonX[0];
	double maxY = polygonY[0];

	for (int i=0;i<polygonY.size();++i) {
		if (polygonX[i] < minX) minX = polygonX[i];
		if (polygonY[i] < minY) minY = polygonY[i];
		if (polygonX[i] > maxX) maxX = polygonX[i];
		if (polygonY[i] > maxY) maxY = polygonY[i];
	}

	rectangleX.push_back(minX);
	rectangleX.push_back(maxX);
	rectangleX.push_back(maxX);
	rectangleX.push_back(minX);

	rectangleY.push_back(maxY);
	rectangleY.push_back(maxY);
	rectangleY.push_back(minY);
	rectangleY.push_back(minY);
}

//计算直线与多边形的交点
void TopologicalAnalysis::linePolygonIntersections(const Point2D& linePt1,const Point2D& linePt2,const vector<double>& polygonX,const vector<double>& polygonY, vector<Point2D>& result)
{
	Line2D line1;
	line1.p1 = linePt1;
	line1.p2 = linePt2;
	Point2D intersectionPt;
	vector<Point2D> resPoints;
	for (int i=0;i<polygonX.size()-1;++i)
	{
		Point2D pt1,pt2;
		pt1.x = polygonX[i];
		pt1.y = polygonY[i];
		pt2.x = polygonX[i+1];
		pt2.y = polygonY[i+1];
		Line2D line2;
		line2.p1 = pt1;
		line2.p2 = pt2;

		int type = isLineIntersecting(line1,line2,intersectionPt);
		if (type == 1 || type == 2) //相交或重合
		{
			resPoints.push_back(intersectionPt);
		}
	}

	if (resPoints.size()>0)
	{
		//获取最左或者最右的两个点,忽略凹多边形中间交点
		double minX = resPoints[0].x;
		double maxX = resPoints[0].x;
		int minIndex = 0;
		int maxIndex = 0;

		for (int i=0;i<resPoints.size();++i) {
			if (resPoints[i].x < minX) minIndex = i;
			if (resPoints[i].x > maxX) maxIndex = i;
		}
		result.push_back(resPoints[minIndex]);
		result.push_back(resPoints[maxIndex]);
	}

}

// 判断两条线段是否相交
int TopologicalAnalysis::isLineIntersecting(const Line2D& l1, const Line2D& l2, Point2D& intersection) {
	float  numera = (l2.p2.x-l2.p1.x) * (l1.p1.y-l2.p1.y) - (l2.p2.y-l2.p1.y) * (l1.p1.x-l2.p1.x);
	float  numerb = (l1.p2.x-l1.p1.x) * (l1.p1.y-l2.p1.y) - (l1.p2.y-l1.p1.y) * (l1.p1.x-l2.p1.x);

	float  denom  = (l2.p2.y-l2.p1.y) * (l1.p2.x-l1.p1.x) - (l2.p2.x-l2.p1.x) * (l1.p2.y-l1.p1.y);

	if(denom == 0.0f)
	{
		if(numera == 0.0f && numerb == 0.0f)
		{
			intersection.x = l2.p2.x;
			intersection.y = l2.p2.y;
			return 2; //重合
		}
		return 3; //平行
	}

	float ua = numera / denom;
	float ub = numerb / denom;

	if(ua >= 0.0f && ua <= 1.0f && ub >= 0.0f && ub <= 1.0f)
	{
		intersection.x = l1.p1.x + ua*(l1.p2.x - l1.p1.x);
		intersection.y = l1.p1.y + ua*(l1.p2.y - l1.p1.y);

		return 1; //相交
	}

	return 0; //不相交
}