Пример #1
0
        //不能出现A多边形的连接两条边的顶点在B多边形的一条边上的情况
        public static List <Polygon> Union(Polygon clip, Polygon subject)
        {
            var ret = new List <Polygon>();

            pClip    = clip;
            pSubject = subject;

            //包围盒不相交
            if (pSubject.boxRectangle.IsIntersect(pClip.boxRectangle) == false)
            {
                return(null);
            }

            //所有顶点和交点
            lnClip    = PolygonNodeUtil.CreateNodes(clip, false, false);          //副多边形
            lnSubject = PolygonNodeUtil.CreateNodes(subject, false, true);        //主多边形

            //插入交点
            var insCnt = IntersectPoint_Union();

            //生成多边形
            if (insCnt > 0)
            {
                ret = LinkToPolygon_Union();
                return(ret);
            }

            return(null);
        }
Пример #2
0
        public static List <Polygon> Cut(Polygon clip, Polygon subject)
        {
            var ret = new List <Polygon>();

            pClip    = clip;
            pSubject = subject;

            //包围盒不相交
            if (pSubject.boxRectangle.IsIntersect(pClip.boxRectangle) == false)
            {
                return(null);
            }

            //所有顶点和交点
            lnClip    = PolygonNodeUtil.CreateNodes(pClip, false, false);          //副多边形
            lnSubject = PolygonNodeUtil.CreateNodes(pSubject, false, true);        //主多边形

            //插入交点
            var insCnt = IntersectPoint_Cut();


            //生成多边形
            if (insCnt > 0)
            {
                ret = LinkToPolygon_Cut();
                return(ret);
            }

            //0个交点
            //要判断是否主多边形包含副多边形,如果包含,则返回副多边形
            var AContainB = true;

            foreach (var line in pClip.lineList)
            {
                if (!pSubject.Contains(line))
                {
                    AContainB = false;
                }
            }
            if (AContainB)
            {
                ret.Add(pClip);
                return(ret);
            }

            //要判断是否副多边形包含主多边形,如果包含,则返回主多边形
            var BContainA = true;

            for (var i = 0; i < pSubject.lineList.Count; i++)
            {
                var line = pSubject.lineList[i];
                if (!pClip.Contains(line))
                {
                    BContainA = false;
                }
            }

            if (BContainA)
            {
                ret.Add(pSubject);
                return(ret);
            }

            return(null);
        }