예제 #1
0
        /// <summary>
        /// 判断点是否在线上
        /// </summary>
        /// <param name="p">点</param>
        /// <param name="line">线</param>
        /// <returns>在线上则返回true否则返回false</returns>
        /// 公式:Point on the Line of the Segment:(P - A)×(B - A) = 0
        public static bool PointOnTheLine(Point p, LineSegment line)
        {
            if (!Rectangle.PointInRectangle(p, new Rectangle(line)))
                return false;

            double cross = Point.CrossProduct(p - line.A, line.B - line.A);
            return Math.Abs(cross) < Polygon.DeviationValue;
        }
예제 #2
0
        public Rectangle(LineSegment line)
        {
            X = Math.Min(line.A.X, line.B.X);
            Y = Math.Min(line.A.Y, line.B.Y);

            Width = Math.Max(line.A.X, line.B.X) - X;
            Height = Math.Max(line.A.Y, line.B.Y) - Y;
        }
예제 #3
0
        /// <summary>
        /// 判断点在线的哪一边
        /// </summary>
        /// <param name="p">点</param>
        /// <param name="line">线</param>
        /// <returns>小于0则左边,大于0则右边,等于0则在线上</returns>
        public static LineSideType PointOnTheLineWhichSide(Point p, LineSegment line)
        {
            double cross = Point.CrossProduct(p - line.A, line.B - line.A);

            bool result = Math.Abs(cross) < Polygon.DeviationValue;

            if (result)
                return LineSideType.On;

            result = cross < 0;

            if (result)
                return LineSideType.Left;
            else
                return LineSideType.Right;
        }
예제 #4
0
        /// <summary>
        /// 判断两条线是否相交
        /// </summary>
        /// <param name="line1">线1</param>
        /// <param name="line2">线2</param>
        /// <returns>有相交返回true,否则返回false</returns>
        public static bool LineSegmentIntersection(LineSegment line1, LineSegment line2)
        {
            if (!Rectangle.CheckTwoRectanglesIntersect(new Rectangle(line1), new Rectangle(line2)))
                return false;

            LineSideType line1ASideType = PointOnTheLineWhichSide(line1.A, line2);
            LineSideType line1BSideType = PointOnTheLineWhichSide(line1.B, line2);

            if (!Check(line1ASideType, line1BSideType))
                return false;

            line1ASideType = PointOnTheLineWhichSide(line2.A, line1);
            line1BSideType = PointOnTheLineWhichSide(line2.B, line1);

            if (!Check(line1ASideType, line1BSideType))
                return false;

            return true;
        }
예제 #5
0
파일: Polygon.cs 프로젝트: hhahh2011/CH.Gps
        public static bool PointInTheMaxRectangle(Point p, Polygon polygon)
        {
            double maxX = polygon.Points.Max(u => u.X);
            double minX = polygon.Points.Min(u => u.X);
            double maxY = polygon.Points.Max(u => u.Y);
            double minY = polygon.Points.Min(u => u.Y);

            LineSegment line = new LineSegment(new Point(maxX, maxY), new Point(minX, minY));

            Rectangle rec = new Rectangle(line);

            return Rectangle.PointInRectangle(p, rec);
        }
예제 #6
0
파일: Polygon.cs 프로젝트: hhahh2011/CH.Gps
        private static bool LineSegmentIntersectionInPolygonLine(Point p, Polygon polygon)
        {
            int intersectionCount = 0;

            double maxX = GetMaxPointX(polygon.Points);

            if (p.X > maxX)
            {
                maxX = p.X + 1;
            }
            else
            {
                maxX += 1;
            }

            LineSegment mainLine = new LineSegment(p, new Point(maxX, p.Y));


            for (int i = 0, j = 1; j < polygon.Points.Count; i++, j++)
            {
                LineSegment line = new LineSegment(polygon.Points[i], polygon.Points[j]);

                bool result = LineSegment.LineSegmentIntersection(mainLine, line);
                if (result)
                    intersectionCount++;
            }

            LineSegment lastLine = new LineSegment(polygon.Points[polygon.Points.Count - 1], polygon.Points[0]);

            bool lastResult = LineSegment.LineSegmentIntersection(mainLine, lastLine);
            if (lastResult)
                intersectionCount++;

            if ((intersectionCount % 2) == 0)
                return false;

            return true;
        }
예제 #7
0
파일: Polygon.cs 프로젝트: hhahh2011/CH.Gps
        private static bool CheckPointOnPolygonLine(Point p, Polygon polygon)
        {

            for (int i = 0, j = 1; j < polygon.Points.Count; i++, j++)
            {
                LineSegment line = new LineSegment(polygon.Points[i], polygon.Points[j]);

                if (LineSegment.PointOnTheLine(p, line))
                    return true;
            }

            LineSegment lastLine = new LineSegment(polygon.Points[polygon.Points.Count - 1], polygon.Points[0]);

            if (LineSegment.PointOnTheLine(p, lastLine))
                return true;

            return false;
        }