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WPF Diagram Designer - Part 4

, 26 Mar 2008 CPOL
A Frankenbuild
diagramdesignerpart4.zip
DiagramDesigner
Controls
DiagramDesigner.csproj.user
Properties
Settings.settings
Resources
Images
AlignObjectsBottom.png
AlignObjectsCenteredHorizontal.png
AlignObjectsCenteredVertical.png
AlignObjectsLeft.png
AlignObjectsRight.png
AlignObjectsTop.png
BringForward.png
BringToFront.png
Copy.png
Cut.png
Delete.png
DistributeObjectsHorizontal.png
DistributeObjectsVertical.png
GenericDocument.png
Group.png
OpenFolder.png
Paste.png
PasteBig.png
Print.png
Save.png
SendBackward.png
SendToBack.png
Ungroup.png
Stencils
Styles
using System;
using System.Collections.Generic;
using System.Windows;
using System.Windows.Controls;

namespace DiagramDesigner
{
    // Note: I couldn't find a useful open source library that does
    // orthogonal routing so started to write something on my own.
    // Categorize this as a quick and dirty short term solution.
    // I will keep on searching.

    // Helper class to provide an orthogonal connection path
    internal class PathFinder
    {
        private const int margin = 20;

        internal static List<Point> GetConnectionLine(ConnectorInfo source, ConnectorInfo sink, bool showLastLine)
        {
            List<Point> linePoints = new List<Point>();

            Rect rectSource = GetRectWithMargin(source, margin);
            Rect rectSink = GetRectWithMargin(sink, margin);

            Point startPoint = GetOffsetPoint(source, rectSource);
            Point endPoint = GetOffsetPoint(sink, rectSink);

            linePoints.Add(startPoint);
            Point currentPoint = startPoint;

            if (!rectSink.Contains(currentPoint) && !rectSource.Contains(endPoint))
            {
                while (true)
                {
                    #region source node

                    if (IsPointVisible(currentPoint, endPoint, new Rect[] { rectSource, rectSink }))
                    {
                        linePoints.Add(endPoint);
                        currentPoint = endPoint;
                        break;
                    }

                    Point neighbour = GetNearestVisibleNeighborSink(currentPoint, endPoint, sink, rectSource, rectSink);
                    if (!double.IsNaN(neighbour.X))
                    {
                        linePoints.Add(neighbour);
                        linePoints.Add(endPoint);
                        currentPoint = endPoint;
                        break;
                    }

                    if (currentPoint == startPoint)
                    {
                        bool flag;
                        Point n = GetNearestNeighborSource(source, endPoint, rectSource, rectSink, out flag);
                        linePoints.Add(n);
                        currentPoint = n;

                        if (!IsRectVisible(currentPoint, rectSink, new Rect[] { rectSource }))
                        {
                            Point n1, n2;
                            GetOppositeCorners(source.Orientation, rectSource, out n1, out n2);
                            if (flag)
                            {
                                linePoints.Add(n1);
                                currentPoint = n1;
                            }
                            else
                            {
                                linePoints.Add(n2);
                                currentPoint = n2;
                            }
                            if (!IsRectVisible(currentPoint, rectSink, new Rect[] { rectSource }))
                            {
                                if (flag)
                                {
                                    linePoints.Add(n2);
                                    currentPoint = n2;
                                }
                                else
                                {
                                    linePoints.Add(n1);
                                    currentPoint = n1;
                                }
                            }
                        }
                    }
                    #endregion

                    #region sink node

                    else // from here on we jump to the sink node
                    {
                        Point n1, n2; // neighbour corner
                        Point s1, s2; // opposite corner
                        GetNeighborCorners(sink.Orientation, rectSink, out s1, out s2);
                        GetOppositeCorners(sink.Orientation, rectSink, out n1, out n2);

                        bool n1Visible = IsPointVisible(currentPoint, n1, new Rect[] { rectSource, rectSink });
                        bool n2Visible = IsPointVisible(currentPoint, n2, new Rect[] { rectSource, rectSink });

                        if (n1Visible && n2Visible)
                        {
                            if (rectSource.Contains(n1))
                            {
                                linePoints.Add(n2);
                                if (rectSource.Contains(s2))
                                {
                                    linePoints.Add(n1);
                                    linePoints.Add(s1);
                                }
                                else
                                    linePoints.Add(s2);

                                linePoints.Add(endPoint);
                                currentPoint = endPoint;
                                break;
                            }

                            if (rectSource.Contains(n2))
                            {
                                linePoints.Add(n1);
                                if (rectSource.Contains(s1))
                                {
                                    linePoints.Add(n2);
                                    linePoints.Add(s2);
                                }
                                else
                                    linePoints.Add(s1);

                                linePoints.Add(endPoint);
                                currentPoint = endPoint;
                                break;
                            }

                            if ((Distance(n1, endPoint) <= Distance(n2, endPoint)))
                            {
                                linePoints.Add(n1);
                                if (rectSource.Contains(s1))
                                {
                                    linePoints.Add(n2);
                                    linePoints.Add(s2);
                                }
                                else
                                    linePoints.Add(s1);
                                linePoints.Add(endPoint);
                                currentPoint = endPoint;
                                break;
                            }
                            else
                            {
                                linePoints.Add(n2);
                                if (rectSource.Contains(s2))
                                {
                                    linePoints.Add(n1);
                                    linePoints.Add(s1);
                                }
                                else
                                    linePoints.Add(s2);
                                linePoints.Add(endPoint);
                                currentPoint = endPoint;
                                break;
                            }
                        }
                        else if (n1Visible)
                        {
                            linePoints.Add(n1);
                            if (rectSource.Contains(s1))
                            {
                                linePoints.Add(n2);
                                linePoints.Add(s2);
                            }
                            else
                                linePoints.Add(s1);
                            linePoints.Add(endPoint);
                            currentPoint = endPoint;
                            break;
                        }
                        else
                        {
                            linePoints.Add(n2);
                            if (rectSource.Contains(s2))
                            {
                                linePoints.Add(n1);
                                linePoints.Add(s1);
                            }
                            else
                                linePoints.Add(s2);
                            linePoints.Add(endPoint);
                            currentPoint = endPoint;
                            break;
                        }
                    }
                    #endregion
                }
            }
            else
            {
                linePoints.Add(endPoint);
            }

            linePoints = OptimizeLinePoints(linePoints, new Rect[] { rectSource, rectSink }, source.Orientation, sink.Orientation);

            CheckPathEnd(source, sink, showLastLine, linePoints);
            return linePoints;
        }        

        internal static List<Point> GetConnectionLine(ConnectorInfo source, Point sinkPoint, ConnectorOrientation preferredOrientation)
        {
            List<Point> linePoints = new List<Point>();
            Rect rectSource = GetRectWithMargin(source, 10);
            Point startPoint = GetOffsetPoint(source, rectSource);
            Point endPoint = sinkPoint;

            linePoints.Add(startPoint);
            Point currentPoint = startPoint;

            if (!rectSource.Contains(endPoint))
            {
                while (true)
                {
                    if (IsPointVisible(currentPoint, endPoint, new Rect[] { rectSource }))
                    {
                        linePoints.Add(endPoint);
                        break;
                    }

                    bool sideFlag;
                    Point n = GetNearestNeighborSource(source, endPoint, rectSource, out sideFlag);
                    linePoints.Add(n);
                    currentPoint = n;

                    if (IsPointVisible(currentPoint, endPoint, new Rect[] { rectSource }))
                    {
                        linePoints.Add(endPoint);
                        break;
                    }
                    else
                    {
                        Point n1, n2;
                        GetOppositeCorners(source.Orientation, rectSource, out n1, out n2);
                        if (sideFlag)
                            linePoints.Add(n1);
                        else
                            linePoints.Add(n2);

                        linePoints.Add(endPoint);
                        break;
                    }
                }
            }
            else
            {
                linePoints.Add(endPoint);
            }

            if (preferredOrientation != ConnectorOrientation.None)
                linePoints = OptimizeLinePoints(linePoints, new Rect[] { rectSource }, source.Orientation, preferredOrientation);
            else
                linePoints = OptimizeLinePoints(linePoints, new Rect[] { rectSource }, source.Orientation, GetOpositeOrientation(source.Orientation));

            return linePoints;
        }

        private static List<Point> OptimizeLinePoints(List<Point> linePoints, Rect[] rectangles, ConnectorOrientation sourceOrientation, ConnectorOrientation sinkOrientation)
        {
            List<Point> points = new List<Point>();
            int cut = 0;

            for (int i = 0; i < linePoints.Count; i++)
            {
                if (i >= cut)
                {
                    for (int k = linePoints.Count - 1; k > i; k--)
                    {
                        if (IsPointVisible(linePoints[i], linePoints[k], rectangles))
                        {
                            cut = k;
                            break;
                        }
                    }
                    points.Add(linePoints[i]);
                }
            }

            #region Line
            for (int j = 0; j < points.Count - 1; j++)
            {
                if (points[j].X != points[j + 1].X && points[j].Y != points[j + 1].Y)
                {
                    ConnectorOrientation orientationFrom;
                    ConnectorOrientation orientationTo;

                    // orientation from point
                    if (j == 0)
                        orientationFrom = sourceOrientation;
                    else
                        orientationFrom = GetOrientation(points[j], points[j - 1]);

                    // orientation to pint 
                    if (j == points.Count - 2)
                        orientationTo = sinkOrientation;
                    else
                        orientationTo = GetOrientation(points[j + 1], points[j + 2]);


                    if ((orientationFrom == ConnectorOrientation.Left || orientationFrom == ConnectorOrientation.Right) &&
                        (orientationTo == ConnectorOrientation.Left || orientationTo == ConnectorOrientation.Right))
                    {
                        double centerX = Math.Min(points[j].X, points[j + 1].X) + Math.Abs(points[j].X - points[j + 1].X) / 2;
                        points.Insert(j + 1, new Point(centerX, points[j].Y));
                        points.Insert(j + 2, new Point(centerX, points[j + 2].Y));
                        if (points.Count - 1 > j + 3)
                            points.RemoveAt(j + 3);
                        return points;
                    }

                    if ((orientationFrom == ConnectorOrientation.Top || orientationFrom == ConnectorOrientation.Bottom) &&
                        (orientationTo == ConnectorOrientation.Top || orientationTo == ConnectorOrientation.Bottom))
                    {
                        double centerY = Math.Min(points[j].Y, points[j + 1].Y) + Math.Abs(points[j].Y - points[j + 1].Y) / 2;
                        points.Insert(j + 1, new Point(points[j].X, centerY));
                        points.Insert(j + 2, new Point(points[j + 2].X, centerY));
                        if (points.Count - 1 > j + 3)
                            points.RemoveAt(j + 3);
                        return points;
                    }

                    if ((orientationFrom == ConnectorOrientation.Left || orientationFrom == ConnectorOrientation.Right) &&
                        (orientationTo == ConnectorOrientation.Top || orientationTo == ConnectorOrientation.Bottom))
                    {
                        points.Insert(j + 1, new Point(points[j + 1].X, points[j].Y));
                        return points;
                    }

                    if ((orientationFrom == ConnectorOrientation.Top || orientationFrom == ConnectorOrientation.Bottom) &&
                        (orientationTo == ConnectorOrientation.Left || orientationTo == ConnectorOrientation.Right))
                    {
                        points.Insert(j + 1, new Point(points[j].X, points[j + 1].Y));
                        return points;
                    }
                }
            }
            #endregion

            return points;
        }

        private static ConnectorOrientation GetOrientation(Point p1, Point p2)
        {
            if (p1.X == p2.X)
            {
                if (p1.Y >= p2.Y)
                    return ConnectorOrientation.Bottom;
                else
                    return ConnectorOrientation.Top;
            }
            else if (p1.Y == p2.Y)
            {
                if (p1.X >= p2.X)
                    return ConnectorOrientation.Right;
                else
                    return ConnectorOrientation.Left;
            }
            throw new Exception("Failed to retrieve orientation");
        }

        private static Orientation GetOrientation(ConnectorOrientation sourceOrientation)
        {
            switch (sourceOrientation)
            {
                case ConnectorOrientation.Left:
                    return Orientation.Horizontal;
                case ConnectorOrientation.Top:
                    return Orientation.Vertical;
                case ConnectorOrientation.Right:
                    return Orientation.Horizontal;
                case ConnectorOrientation.Bottom:
                    return Orientation.Vertical;
                default:
                    throw new Exception("Unknown ConnectorOrientation");
            }
        }

        private static Point GetNearestNeighborSource(ConnectorInfo source, Point endPoint, Rect rectSource, Rect rectSink, out bool flag)
        {
            Point n1, n2; // neighbors
            GetNeighborCorners(source.Orientation, rectSource, out n1, out n2);

            if (rectSink.Contains(n1))
            {
                flag = false;
                return n2;
            }

            if (rectSink.Contains(n2))
            {
                flag = true;
                return n1;
            }

            if ((Distance(n1, endPoint) <= Distance(n2, endPoint)))
            {
                flag = true;
                return n1;
            }
            else
            {
                flag = false;
                return n2;
            }
        }

        private static Point GetNearestNeighborSource(ConnectorInfo source, Point endPoint, Rect rectSource, out bool flag)
        {
            Point n1, n2; // neighbors
            GetNeighborCorners(source.Orientation, rectSource, out n1, out n2);

            if ((Distance(n1, endPoint) <= Distance(n2, endPoint)))
            {
                flag = true;
                return n1;
            }
            else
            {
                flag = false;
                return n2;
            }
        }

        private static Point GetNearestVisibleNeighborSink(Point currentPoint, Point endPoint, ConnectorInfo sink, Rect rectSource, Rect rectSink)
        {
            Point s1, s2; // neighbors on sink side
            GetNeighborCorners(sink.Orientation, rectSink, out s1, out s2);

            bool flag1 = IsPointVisible(currentPoint, s1, new Rect[] { rectSource, rectSink });
            bool flag2 = IsPointVisible(currentPoint, s2, new Rect[] { rectSource, rectSink });

            if (flag1) // s1 visible
            {
                if (flag2) // s1 and s2 visible
                {
                    if (rectSink.Contains(s1))
                        return s2;

                    if (rectSink.Contains(s2))
                        return s1;

                    if ((Distance(s1, endPoint) <= Distance(s2, endPoint)))
                        return s1;
                    else
                        return s2;

                }
                else
                {
                    return s1;
                }
            }
            else // s1 not visible
            {
                if (flag2) // only s2 visible
                {
                    return s2;
                }
                else // s1 and s2 not visible
                {
                    return new Point(double.NaN, double.NaN);
                }
            }
        }

        private static bool IsPointVisible(Point fromPoint, Point targetPoint, Rect[] rectangles)
        {
            foreach (Rect rect in rectangles)
            {
                if (RectangleIntersectsLine(rect, fromPoint, targetPoint))
                    return false;
            }
            return true;
        }

        private static bool IsRectVisible(Point fromPoint, Rect targetRect, Rect[] rectangles)
        {
            if (IsPointVisible(fromPoint, targetRect.TopLeft, rectangles))
                return true;

            if (IsPointVisible(fromPoint, targetRect.TopRight, rectangles))
                return true;

            if (IsPointVisible(fromPoint, targetRect.BottomLeft, rectangles))
                return true;

            if (IsPointVisible(fromPoint, targetRect.BottomRight, rectangles))
                return true;

            return false;
        }

        private static bool RectangleIntersectsLine(Rect rect, Point startPoint, Point endPoint)
        {
            rect.Inflate(-1, -1);
            return rect.IntersectsWith(new Rect(startPoint, endPoint));
        }

        private static void GetOppositeCorners(ConnectorOrientation orientation, Rect rect, out Point n1, out Point n2)
        {
            switch (orientation)
            {
                case ConnectorOrientation.Left:
                    n1 = rect.TopRight; n2 = rect.BottomRight;
                    break;
                case ConnectorOrientation.Top:
                    n1 = rect.BottomLeft; n2 = rect.BottomRight;
                    break;
                case ConnectorOrientation.Right:
                    n1 = rect.TopLeft; n2 = rect.BottomLeft;
                    break;
                case ConnectorOrientation.Bottom:
                    n1 = rect.TopLeft; n2 = rect.TopRight;
                    break;
                default:
                    throw new Exception("No opposite corners found!");
            }
        }

        private static void GetNeighborCorners(ConnectorOrientation orientation, Rect rect, out Point n1, out Point n2)
        {
            switch (orientation)
            {
                case ConnectorOrientation.Left:
                    n1 = rect.TopLeft; n2 = rect.BottomLeft;
                    break;
                case ConnectorOrientation.Top:
                    n1 = rect.TopLeft; n2 = rect.TopRight;
                    break;
                case ConnectorOrientation.Right:
                    n1 = rect.TopRight; n2 = rect.BottomRight;
                    break;
                case ConnectorOrientation.Bottom:
                    n1 = rect.BottomLeft; n2 = rect.BottomRight;
                    break;
                default:
                    throw new Exception("No neighour corners found!");
            }
        }

        private static double Distance(Point p1, Point p2)
        {
            return Point.Subtract(p1, p2).Length;
        }

        private static Rect GetRectWithMargin(ConnectorInfo connectorThumb, double margin)
        {
            Rect rect = new Rect(connectorThumb.DesignerItemLeft,
                                 connectorThumb.DesignerItemTop,
                                 connectorThumb.DesignerItemSize.Width,
                                 connectorThumb.DesignerItemSize.Height);

            rect.Inflate(margin, margin);

            return rect;
        }

        private static Point GetOffsetPoint(ConnectorInfo connector, Rect rect)
        {
            Point offsetPoint = new Point();

            switch (connector.Orientation)
            {
                case ConnectorOrientation.Left:
                    offsetPoint = new Point(rect.Left, connector.Position.Y);
                    break;
                case ConnectorOrientation.Top:
                    offsetPoint = new Point(connector.Position.X, rect.Top);
                    break;
                case ConnectorOrientation.Right:
                    offsetPoint = new Point(rect.Right, connector.Position.Y);
                    break;
                case ConnectorOrientation.Bottom:
                    offsetPoint = new Point(connector.Position.X, rect.Bottom);
                    break;
                default:
                    break;
            }

            return offsetPoint;
        }

        private static void CheckPathEnd(ConnectorInfo source, ConnectorInfo sink, bool showLastLine, List<Point> linePoints)
        {
            if (showLastLine)
            {
                Point startPoint = new Point(0, 0);
                Point endPoint = new Point(0, 0);
                double marginPath = 15;
                switch (source.Orientation)
                {
                    case ConnectorOrientation.Left:
                        startPoint = new Point(source.Position.X - marginPath, source.Position.Y);
                        break;
                    case ConnectorOrientation.Top:
                        startPoint = new Point(source.Position.X, source.Position.Y - marginPath);
                        break;
                    case ConnectorOrientation.Right:
                        startPoint = new Point(source.Position.X + marginPath, source.Position.Y);
                        break;
                    case ConnectorOrientation.Bottom:
                        startPoint = new Point(source.Position.X, source.Position.Y + marginPath);
                        break;
                    default:
                        break;
                }

                switch (sink.Orientation)
                {
                    case ConnectorOrientation.Left:
                        endPoint = new Point(sink.Position.X - marginPath, sink.Position.Y);
                        break;
                    case ConnectorOrientation.Top:
                        endPoint = new Point(sink.Position.X, sink.Position.Y - marginPath);
                        break;
                    case ConnectorOrientation.Right:
                        endPoint = new Point(sink.Position.X + marginPath, sink.Position.Y);
                        break;
                    case ConnectorOrientation.Bottom:
                        endPoint = new Point(sink.Position.X, sink.Position.Y + marginPath);
                        break;
                    default:
                        break;
                }
                linePoints.Insert(0, startPoint);
                linePoints.Add(endPoint);
            }
            else
            {
                linePoints.Insert(0, source.Position);
                linePoints.Add(sink.Position);
            }
        }

        private static ConnectorOrientation GetOpositeOrientation(ConnectorOrientation connectorOrientation)
        {
            switch (connectorOrientation)
            {
                case ConnectorOrientation.Left:
                    return ConnectorOrientation.Right;
                case ConnectorOrientation.Top:
                    return ConnectorOrientation.Bottom;
                case ConnectorOrientation.Right:
                    return ConnectorOrientation.Left;
                case ConnectorOrientation.Bottom:
                    return ConnectorOrientation.Top;
                default:
                    return ConnectorOrientation.Top;
            }
        }
    }
}

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sukram

Austria Austria
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