mcs/class/referencesource/System.Activities.Presentation/System.Activities.Presentation/System/Activities/Presentation/FreeFormEditing/ConnectionPoint.cs

   1 //------------------------------------------------------------
   2 // Copyright (c) Microsoft Corporation.  All rights reserved.
   3 //------------------------------------------------------------
   4
   5 namespace System.Activities.Presentation.FreeFormEditing
   6 {
   7     using System.Collections.Generic;
   8     using System.Diagnostics;
   9     using System.Windows;
  10     using System.Runtime;
  11     class ConnectionPoint : UIElement
  12     {
  13         public static readonly DependencyProperty LocationProperty = DependencyProperty.Register("Location", typeof(Point), typeof(ConnectionPoint));
  14
  15         private List<Connector> attachedConnectors;
  16         private UIElement parentDesigner;
  17         private ConnectionPointKind pointType;
  18
  19         // Size constants for the rectangle drawn
  20         internal const double DrawingSmallSide = 4;
  21         internal const double DrawingLargeSide = 10;
  22
  23         // Size constants for the hit test area.
  24         internal const double HitTestSmallSide = 14;
  25         internal const double HitTestLargeSide = 20;
  26
  27         public ConnectionPoint()
  28         {
  29             pointType = ConnectionPointKind.Default;
  30             attachedConnectors = new List<Connector>();
  31             this.parentDesigner = null;
  32         }
  33
  34         public List<Connector> AttachedConnectors
  35         {
  36             get
  37             {
  38                 return this.attachedConnectors;
  39             }
  40         }
  41
  42         public Point Location
  43         {
  44             get { return (Point)GetValue(ConnectionPoint.LocationProperty); }
  45             set { SetValue(ConnectionPoint.LocationProperty, value); }
  46         }
  47
  48         // This is the vector from the point on the Edge to the top left of the rectangle being drawn.
  49         public Vector DrawingOffset
  50         {
  51             get
  52             {
  53                 return GetOffset(DrawingSmallSide, DrawingLargeSide);
  54             }
  55         }
  56
  57         // This is the vector from the point on the Edge to the top left of the rectangle being used for hit test.
  58         public Vector HitTestOffset
  59         {
  60             get
  61             {
  62                 return GetOffset(HitTestSmallSide, HitTestLargeSide);
  63             }
  64         }
  65
  66         // This is the size for the rectangle drawn (size is independent of coordinate system)
  67         public Size DrawingSize
  68         {
  69             get
  70             {
  71                 return this.GetSize(ConnectionPoint.DrawingSmallSide, ConnectionPoint.DrawingLargeSide);
  72             }
  73         }
  74
  75         // This is the size for the hit test area (size is independent of coordinate system)
  76         public Size HitTestSize
  77         {
  78             get
  79             {
  80                 return this.GetSize(ConnectionPoint.HitTestSmallSide, ConnectionPoint.HitTestLargeSide);
  81             }
  82         }
  83
  84         public UIElement ParentDesigner
  85         {
  86             get
  87             {
  88                 return this.parentDesigner;
  89             }
  90             set
  91             {
  92                 this.parentDesigner = value;
  93             }
  94         }
  95
  96         public ConnectionPointKind PointType
  97         {
  98             get
  99             {
 100                 return this.pointType;
 101             }
 102             set
 103             {
 104                 this.pointType = value;
 105             }
 106         }
 107
 108         // The list of Points representing the edge of the parent designer where this ConnectionPoint locates with respect to (0,0) of the FreeFormPanel.
 109         public List<Point> Edge
 110         {
 111             get
 112             {
 113                 FrameworkElement parent = this.ParentDesigner as FrameworkElement;
 114                 Fx.Assert(parent != null, "shape should be a FrameworkElement");
 115                 Point topLeft = FreeFormPanel.GetLocation(parent);
 116                 topLeft.Offset(parent.Margin.Left, parent.Margin.Top);
 117                 double parentWidth = parent.DesiredSize.Width - parent.Margin.Left - parent.Margin.Right;
 118                 double parentHeight = parent.DesiredSize.Height - parent.Margin.Top - parent.Margin.Bottom;
 119                 if (this.Location.X == topLeft.X)
 120                 { //Left Edge
 121                     return new List<Point> { topLeft, new Point(topLeft.X, topLeft.Y + parentHeight) };
 122                 }
 123                 else if (this.Location.X == topLeft.X + parentWidth)
 124                 { //Right edge
 125                     return new List<Point> { new Point(topLeft.X + parentWidth, topLeft.Y), new Point(topLeft.X + parentWidth, topLeft.Y + parentHeight) };
 126                 }
 127                 else if (this.Location.Y == topLeft.Y)
 128                 { //Top Edge
 129                     return new List<Point> { topLeft, new Point(topLeft.X + parentWidth, topLeft.Y) };
 130                 }
 131                 else if (this.Location.Y == topLeft.Y + parentHeight)
 132                 { //Bottom edge
 133                     return new List<Point> { new Point(topLeft.X, topLeft.Y + parentHeight), new Point(topLeft.X + parentWidth, topLeft.Y + parentHeight) };
 134                 }
 135                 return null;
 136             }
 137         }
 138
 139         public EdgeLocation EdgeLocation
 140         {
 141             get;
 142             set;
 143         }
 144
 145         public static ConnectionPoint GetClosestConnectionPoint(List<ConnectionPoint> connectionPoints, Point refPoint, out double minDist)
 146         {
 147             minDist = double.PositiveInfinity;
 148             if (connectionPoints == null || connectionPoints.Count == 0)
 149             {
 150                 return null;
 151             }
 152             double dist = 0;
 153             ConnectionPoint closestPoint = null;
 154             foreach (ConnectionPoint point in connectionPoints)
 155             {
 156                 dist = DesignerGeometryHelper.DistanceBetweenPoints(refPoint, point.Location);
 157                 if (dist < minDist)
 158                 {
 159                     minDist = dist;
 160                     closestPoint = point;
 161                 }
 162             }
 163
 164             return closestPoint;
 165         }
 166
 167         // This is the vector from the point on the Edge to the top left of a rectangle with a particular (small, large) pair.
 168         Vector GetOffset(double small, double large)
 169         {
 170             return this.EdgeToDrawnMidPointOffset() + this.MidPointToTopLeftOffset(small, large);
 171         }
 172
 173         // This is the vector from the point on the Edge to the midpoint of the "drawn" rectangle.
 174         Vector EdgeToDrawnMidPointOffset()
 175         {
 176             double small = ConnectionPoint.DrawingSmallSide;
 177             switch (this.EdgeLocation)
 178             {
 179                 case EdgeLocation.Left: return new Vector(-small / 2, 0);
 180                 case EdgeLocation.Right: return new Vector(small / 2, 0);
 181                 case EdgeLocation.Top: return new Vector(0, -small / 2);
 182                 case EdgeLocation.Bottom: return new Vector(0, small / 2);
 183             }
 184             Fx.Assert("There is no other possibilities for EdgeDirections");
 185             // To please compiler
 186             return new Vector();
 187         }
 188
 189         // This is the vector from the midpoint of the rectangle to the top left of the rectangle with a particular (small, large) pair.
 190         Vector MidPointToTopLeftOffset(double small, double large)
 191         {
 192             Size rectSize = GetSize(small, large);
 193             return new Vector(-rectSize.Width / 2, -rectSize.Height / 2);
 194         }
 195
 196         // This is the size for the rectangle with a particular (small, large) pair
 197         Size GetSize(double small, double large)
 198         {
 199             if (this.EdgeLocation == EdgeLocation.Left || this.EdgeLocation == EdgeLocation.Right)
 200             {
 201                 return new Size(small, large);
 202             }
 203             else
 204             {
 205                 return new Size(large, small);
 206             }
 207         }
 208     }
 209
 210     enum EdgeLocation
 211     {
 212         Left,
 213         Right,
 214         Top,
 215         Bottom
 216     }
 217 }