/// <summary>
/// (pa和pb构成的线段不与任何约束边相交，不包括顶点)
/// </summary>
/// <param name="linePaPb"></param>
/// <returns></returns>
private bool IsIntersectWithEdges(Line linePaPb)
{
Vector2?intersectPoint;
for (var i = 0; i < this.edgeList.Count; i++)
{
Line lineTmp = this.edgeList[i];
//两线段的关系
Line.LineClassification lineRelation = linePaPb.Intersection(lineTmp, out intersectPoint);
if (lineRelation == Line.LineClassification.SegmentsIntersect) //相交
{
//排除端点相交的情况
if (intersectPoint.Value.EqualsEPSILON(linePaPb.pointA) ||
intersectPoint.Value.EqualsEPSILON(linePaPb.pointB))
{
continue; //两条线段不是真正相交，继续检查下一条约束边
}
return(true); //两条线段是真正相交
}
//不相交，检查下一条约束边
}
return(false);
}
/// <summary>
/// 点是否在多边形内部
/// http://www.cnblogs.com/zhangshu/archive/2011/08/08/2130694.html
/// </summary>
/// <param name="point"></param>
/// <returns></returns>
public virtual bool Contains(Vector2 point)
{
int count = 0;
//minValue+100000,因为再减去一个数，会越界
Line L = new Line(new Vector2(float.MinValue + 100000, point.y), point);
for (var i = 0; i < this.lineList.Count; i++)
{
Line S = this.lineList[i];
if (S.ClassifyPoint(point) == PointClassification.OnSegment)
{
return(true);
}
if (!S.GetDirection().EqualsEPSILON(Vector2.right) &&
!S.GetDirection().EqualsEPSILON(-Vector2.right))
{
bool aOnL = L.ClassifyPoint(S.pointA) == PointClassification.OnSegment;
bool bOnL = L.ClassifyPoint(S.pointB) == PointClassification.OnSegment;
if (aOnL || bOnL)
{
if (aOnL && S.pointA.y > S.pointB.y)
{
count++;
}
if (bOnL && S.pointB.y > S.pointA.y)
{
count++;
}
}
else
{
Line.LineClassification lineRelation = S.Intersection(L, out _);
if (lineRelation == Line.LineClassification.SegmentsIntersect)
{
count++;
}
}
}
}
return(count % 2 != 0);
}
