/// <summary>
/// Fix the ports for <see cref="RoutingMode.ShortestStraightPathToBorder"/>
/// by enlarging the adjacent segment to the rotated layout.
/// </summary>
/// <param name="graph">The layout graph to work on.</param>
/// <param name="edge">The edge to fix.</param>
/// <param name="path">A <see cref="GeneralPath"/> which represents the rotated layout.</param>
/// <param name="atSource">Whether to fix the source or target port of the edge.</param>
private static void FixPorts(LayoutGraph graph, Edge edge, GeneralPath path, bool atSource)
{
var el = graph.GetLayout(edge);
var pointCount = el.PointCount();
// find the opposite point of the port at the adjacent segment
PointD firstBend = atSource
? (pointCount > 0 ? el.GetPoint(0) : graph.GetTargetPointAbs(edge)).ToPointD()
: (pointCount > 0 ? el.GetPoint(pointCount - 1) : graph.GetSourcePointAbs(edge)).ToPointD();
// The port itself
PointD port = (atSource ? graph.GetSourcePointAbs(edge) : graph.GetTargetPointAbs(edge)).ToPointD();
// The adjacent segment as vector pointing from the opposite point to the port
var direction = port - firstBend;
// find the intersection (there is always one)
var intersection = path.FindRayIntersection(firstBend.ToPointD(), direction);
PointD point = port;
if (intersection < Double.PositiveInfinity)
{
// found an intersection: extend the adjacent segment
point = firstBend + (direction * intersection);
}
else
{
// no intersection: connect to the original port's nearest point
var cursor = path.CreateCursor();
double minDistance = Double.PositiveInfinity;
while (cursor.MoveNext())
{
var distance = port.DistanceTo(cursor.CurrentEndPoint);
if (distance < minDistance)
{
minDistance = distance;
point = cursor.CurrentEndPoint;
}
}
}
// set the port position
if (atSource)
{
graph.SetSourcePointAbs(edge, point.ToYPoint());
}
else
{
graph.SetTargetPointAbs(edge, point.ToYPoint());
}
}