C# Segment.Length方法代码示例

        private Segment BruteForce(List<Point> points)
        {
            //Trace.Assert(points.Count >= 2);

            int count = points.Count;

            // Seed the result - doesn't matter what points are used
            // This just avoids having to do null checks in the main loop below
            var result = new Segment(points[0], points[1]);
            var bestLength = result.Length();

            for (int i = 0; i < count; i++)
                for (int j = i + 1; j < count; j++)
                    if (Segment.Length(points[i], points[j]) < bestLength)
                    {
                        result = new Segment(points[i], points[j]);
                        bestLength = result.Length();
                    }

            return result;
        }

        private FollowingTitle getFollowingTitle(Graphics g, LinePath part, double length, string label, TitleStyle titleStyle, BoundingRectangle viewBox, double scaleFactor)
        {
            StringFormat format = StringFormat.GenericTypographic;
            SizeF sizeF;
            PointF zeroPoint = new PointF(0, 0);

            using (Font f = titleStyle.GetFont())
            {
                sizeF = g.MeasureString(label, f, zeroPoint, format);

                // label length must be less than the length of the line
                if (sizeF.Width / scaleFactor < length)
                {
                    LinePath tempPart = new LinePath();
                    foreach (ICoordinate p in part.Vertices)
                        tempPart.Vertices.Add(p);

                    int vertexNumber = 0;
                    ICoordinate centerPoint = getDistantPoint(tempPart.Vertices, length / 2, out vertexNumber);

                    // if the point of the proposed mid-label misses the display area of ​​the map, the inscription does not appear
                    if (!viewBox.ContainsPoint(centerPoint))
                        return null;

                    // simplify the line
                    tempPart.Weed(sizeF.Height / scaleFactor / 2);

                    //get the center point of the simplified line
                    centerPoint = getDistantPoint(tempPart.Vertices, length / 2, out vertexNumber);

                    List<double> leftPointsRotationDeltas = new List<double>();
                    List<double> rightPointsRotationDeltas = new List<double>();

                    // coordinates of points on the left of the middle of the inscription
                    IList<ICoordinate> leftPoints =
                        getLeftPoints(tempPart.Vertices,
                                      centerPoint,
                                      sizeF.Width / 2 / scaleFactor,
                                      vertexNumber,
                                      sizeF.Height / 2 / scaleFactor,
                                      leftPointsRotationDeltas);

                    // coordinates of the points to the right of the middle of the inscription
                    IList<ICoordinate> rightPoints =
                        getRightPoints(tempPart.Vertices,
                                       centerPoint,
                                       sizeF.Width / 2 / scaleFactor,
                                       vertexNumber,
                                       sizeF.Height / 2 / scaleFactor,
                                       rightPointsRotationDeltas);

                    //coordinates of the vertices of the broken line, which will be located along the inscription
                    List<ICoordinate> points = leftPoints.ToList();
                    points.AddRange(rightPoints);

                    // shifts of the inscriptions associated with break lines
                    List<double> rotationDeltas = leftPointsRotationDeltas;
                    rotationDeltas.AddRange(rightPointsRotationDeltas);

                    for (int i = 0; i < points.Count; i++)
                        points[i] = PlanimetryEnvironment.NewCoordinate((points[i].X - viewBox.MinX) * scaleFactor,
                                               (viewBox.MaxY - points[i].Y) * scaleFactor);

                    for (int i = 0; i < rotationDeltas.Count; i++)
                        rotationDeltas[i] = rotationDeltas[i] * scaleFactor;

                    //determine the direction of following labels (direct or reverse)
                    double forwardWeight = 0;
                    double backwardWeight = 0;

                    for (int i = 1; i < points.Count; i++)
                    {
                        Segment s = new Segment(PlanimetryEnvironment.NewCoordinate(points[i].X, points[i].Y),
                                                PlanimetryEnvironment.NewCoordinate(points[i - 1].X, points[i - 1].Y));
                        int quadNumber = pointQuadrantNumber(PlanimetryEnvironment.NewCoordinate(s.V1.X - s.V2.X, s.V1.Y - s.V2.Y));
                        if (quadNumber == 1 || quadNumber == 4)
                            forwardWeight += s.Length();
                        else
                            backwardWeight += s.Length();
                    }

                    if (backwardWeight > forwardWeight)
                    {
                        points.Reverse();
                        rotationDeltas.Reverse();
                    }

                    // inscriptions along the route should not be a large number of points
                    if (label.Length > points.Count - 2)
                    {
                        List<int> subStringLengths = new List<int>();
                        List<double> deltas = new List<double>();

                        LinePath p1 = new LinePath(points.ToArray());
                        double l = p1.Length();

                        // partition of the inscription on the straight parts, the calculation of displacement
                        int startIndex = 0;
                        for (int i = 1; i < points.Count; i++)
                        {
//.........这里部分代码省略.........

        private Segment TargetedSearch(List<Point> points)
        {
            //Trace.Assert(points.Count >= 2);

            int count = points.Count;
            points.Sort((lhs, rhs) => lhs.Coordinates[0].CompareTo(rhs.Coordinates[0]));

            var result = new Segment(points[0], points[1]);
            var bestLength = result.Length();

            for (int i = 0; i < count; i++)
            {
                var from = points[i];

                for (int j = i + 1; j < count; j++)
                {
                    var to = points[j];

                    var dx = to.Coordinates[0] - from.Coordinates[0];
                    if (dx >= bestLength)
                    {
                        break;
                    }

                    if (Segment.Length(from, to) < bestLength)
                    {
                        result = new Segment(from, to);
                        bestLength = result.Length();
                    }
                }
            }

            return result;
        }