double ComputeCostDeltaAfterNodeGluing(Station i, Station j, Dictionary <Station, Station> gluingMap)
{
double d = (i.Position - j.Position).Length;
if (i.Radius >= d || j.Radius >= d)
{
return(1.0);
}
double gain = 0;
//ink
double oldInk = metroGraphData.Ink;
double newInk = metroGraphData.Ink - (j.Position - i.Position).Length;
foreach (var adj in i.Neighbors)
{
var k = Glued(adj, gluingMap);
newInk -= (k.Position - i.Position).Length;
newInk += (metroGraphData.RealEdgeCount(k, j) == 0 ? (k.Position - j.Position).Length : 0);
}
gain += CostCalculator.InkError(oldInk, newInk, bundlingSettings);
//path lengths
foreach (var metroInfo in metroGraphData.MetroNodeInfosOfNode(i))
{
double oldLength = metroInfo.Metroline.Length;
double newLength = metroInfo.Metroline.Length;
PolylinePoint pi = metroInfo.PolyPoint;
PolylinePoint pa = pi.Prev;
PolylinePoint pb = pi.Next;
newLength -= (pa.Point - i.Position).Length + (pb.Point - i.Position).Length;
newLength += (pa.Point - j.Position).Length + (pb.Point - j.Position).Length;
gain += CostCalculator.PathLengthsError(oldLength, newLength, metroInfo.Metroline.IdealLength,
bundlingSettings);
}
return(gain);
}
/// <summary>
/// Gain of path lengths
/// </summary>
internal double PathLengthsGain(Station node, Point newPosition)
{
double gain = 0;
//edge lengths
foreach (var e in metroGraphData.MetroNodeInfosOfNode(node))
{
var oldLength = e.Metroline.Length;
var prev = e.PolyPoint.Prev.Point;
var next = e.PolyPoint.Next.Point;
var newLength = e.Metroline.Length + (next - newPosition).Length + (prev - newPosition).Length - (next - node.Position).Length - (prev - node.Position).Length;
gain += PathLengthsError(oldLength, newLength, e.Metroline.IdealLength, bundlingSettings);
}
return(gain);
}
/// <summary>
/// direction to decrease path lengths
/// </summary>
Point BuildForceForPathLengths(Station node)
{
//return new Point();
var direction = new Point();
foreach (var mni in metroGraphData.MetroNodeInfosOfNode(node))
{
var metroline = mni.Metroline;
Point u = mni.PolyPoint.Next.Point;
Point v = mni.PolyPoint.Prev.Point;
var p1 = u - node.Position;
var p2 = v - node.Position;
direction += p1 / (p1.Length * metroline.IdealLength);
direction += p2 / (p2.Length * metroline.IdealLength);
}
//derivative
Point force = direction * bundlingSettings.PathLengthImportance;
return(force);
}