public TaxiEdge(TaxiNode startNode, TaxiNode endNode, bool isRunway, XPlaneAircraftCategory maxSize, string linkName)
{
StartNode = startNode;
EndNode = endNode;
IsRunway = isRunway;
MaxCategory = maxSize;
LinkName = linkName;
ActiveForRunways = new List <string>();
ActiveZone = false;
ReverseEdge = null;
}
/// <summary>
/// Find the chain of TaxiNodes that represent this runway
/// </summary>
/// <param name="taxiNodes"></param>
/// <param name="taxiEdges"></param>
/// <returns></returns>
private List <TaxiNode> FindNodeChain(IEnumerable <TaxiNode> taxiNodes, IEnumerable <TaxiEdge> taxiEdges)
{
List <TaxiNode> nodes = new List <TaxiNode>();
// Start with the node nearest to the runway lat/lon
TaxiNode currentNode = NearestNode;
nodes.Add(currentNode);
ulong previousNodeId = 0;
do
{
// Now find an edge that is marked as 'runway' and that starts at the current node, but does not lead to the previous node
IEnumerable <TaxiEdge> edgesToNext = taxiEdges.Where(e => e.IsRunway && (e.StartNode.Id == currentNode.Id && e.EndNode.Id != previousNodeId));
if (edgesToNext.Count() == 0)
{
break;
}
TaxiEdge edgeToNext = edgesToNext.First();
if (edgesToNext.Count() > 1)
{
double maxDeviation = double.MaxValue;
foreach (TaxiEdge candidate in edgesToNext)
{
double deviation = VortexMath.TurnAngle(this.Bearing, VortexMath.BearingRadians(currentNode, candidate.EndNode));
if (deviation < maxDeviation)
{
edgeToNext = candidate;
maxDeviation = deviation;
}
}
}
// Keep the current Id as the previous Id
previousNodeId = currentNode.Id;
// And get the new current node
currentNode = taxiNodes.Single(n => n.Id == edgeToNext.EndNode.Id);
if (currentNode != null)
{
nodes.Add(currentNode);
}
}while (currentNode != null);
return(nodes);
}
private void ReadTaxiEdgeOperations(string line)
{
string[] tokens = line.Split(_splitters, StringSplitOptions.RemoveEmptyEntries);
string[] rwys = tokens[2].Split(',');
TaxiEdge lastEdge = _edges.Last();
lastEdge.ActiveZone = true;
lastEdge.ActiveForRunways.AddRange(rwys);
lastEdge.ActiveForRunways = lastEdge.ActiveForRunways.Distinct().ToList();
if (lastEdge.ReverseEdge != null)
{
lastEdge.ReverseEdge.ActiveZone = true;
lastEdge.ReverseEdge.ActiveForRunways.AddRange(rwys);
lastEdge.ReverseEdge.ActiveForRunways = lastEdge.ReverseEdge.ActiveForRunways.Distinct().ToList();
}
}
private void FindExits()
{
ExitGroups.Clear();
TaxiNode groupStartNode = null;
// First, group all nodes
foreach (TaxiNode node in RunwayNodes)
{
foreach (TaxiEdge edge in node.IncomingEdges)
{
if (edge.IsRunway)
{
continue;
}
if (edge.ReverseEdge == null)
{
continue;
}
TaxiEdge actualEdge = edge.ReverseEdge;
double exitAngle = VortexMath.TurnAngle(actualEdge.Bearing, Bearing);
if (Math.Abs(exitAngle) > VortexMath.Deg135Rad)
{
continue;
}
if (groupStartNode == null)
{
groupStartNode = node;
ExitGroups.Add(node, new List <ExitPoint>());
}
double landingLengthUsed = VortexMath.DistanceKM(DisplacedNode, node); // 'distance used' actually
if (VortexMath.DistanceKM(groupStartNode, node) < 0.200)
{
ExitGroups[groupStartNode].Add(new ExitPoint()
{
OffRunwayNode = actualEdge.EndNode, OnRunwayNode = node, LandingLengthUsed = landingLengthUsed, TurnAngle = exitAngle
});
}
else
{
// add to new group
groupStartNode = node;
ExitGroups.Add(node, new List <ExitPoint>());
ExitGroups[groupStartNode].Add(new ExitPoint()
{
OffRunwayNode = actualEdge.EndNode, OnRunwayNode = node, LandingLengthUsed = landingLengthUsed, TurnAngle = exitAngle
});
}
}
}
if (ExitGroups.Count == 0)
{
return; // todo: add warning
}
// Then pick groups based upon distance
List <ExitPoint> minimumExit = null;
List <ExitPoint> mediumExit = null;
List <ExitPoint> longExit = null;
List <ExitPoint> maxExit = null;
foreach (KeyValuePair <TaxiNode, List <ExitPoint> > exitGroup in ExitGroups.OrderBy(eg => eg.Value.First().LandingLengthUsed))
{
if (minimumExit == null || minimumExit.First().LandingLengthUsed < VortexMath.Feet4000Km)
{
minimumExit = exitGroup.Value;
}
else if (mediumExit == null || mediumExit.First().LandingLengthUsed < VortexMath.Feet5000Km)
{
mediumExit = exitGroup.Value;
}
else if (longExit == null || longExit.First().LandingLengthUsed < VortexMath.Feet6500Km)
{
longExit = exitGroup.Value;
}
else
{
maxExit = exitGroup.Value;
}
}
ExitGroups.Clear();
if (minimumExit != null)
{
ExitGroups.Add(minimumExit.First().OnRunwayNode, minimumExit);
}
if (mediumExit != null)
{
ExitGroups.Add(mediumExit.First().OnRunwayNode, mediumExit);
}
if (longExit != null)
{
ExitGroups.Add(longExit.First().OnRunwayNode, longExit);
}
if (maxExit != null)
{
ExitGroups.Add(maxExit.First().OnRunwayNode, maxExit);
}
foreach (var result in ExitGroups)
{
Logger.Log($"{Designator} Group: {result.Key.Id}");
ExitPoint right = result.Value.Where(ep => ep.TurnAngle > 0).OrderBy(ep => ep.TurnAngle).FirstOrDefault();
ExitPoint left = result.Value.Where(ep => ep.TurnAngle < 0).OrderByDescending(ep => ep.TurnAngle).FirstOrDefault();
ExitGroups[result.Key].Clear();
if (right != null)
{
Logger.Log($" Right Exit: {right.OnRunwayNode.Id}->{right.OffRunwayNode.Id} {right.TurnAngle * VortexMath.Rad2Deg:0.0} {right.LandingLengthUsed * VortexMath.KmToFoot:0}ft");
ExitGroups[result.Key].Add(right);
}
if (left != null)
{
Logger.Log($" Left Exit: {left.OnRunwayNode.Id}->{left.OffRunwayNode.Id} {left.TurnAngle * VortexMath.Rad2Deg:0.0} {left.LandingLengthUsed * VortexMath.KmToFoot:0}ft");
ExitGroups[result.Key].Add(left);
}
}
}
public void DetermineTaxiOutLocation(IEnumerable <TaxiNode> taxiNodes)
{
double shortestDistance = double.MaxValue;
double bestPushBackLatitude = 0;
double bestPushBackLongitude = 0;
TaxiNode firstAfterPush = null;
TaxiNode alternateAfterPush = null;
TaxiNode fallback = null;
// For gates use the indicated bearings (push back), for others add 180 degrees for straight out
// Then convert to -180...180 range
double adjustedBearing = (LocationType == StartUpLocationType.Gate) ? Bearing : (Bearing + Math.PI);
if (adjustedBearing > Math.PI)
{
adjustedBearing -= (VortexMath.PI2);
}
// Compute the distance (arbitrary units) from each taxi node to the start location
foreach (TaxiNode node in taxiNodes)
{
node.TemporaryDistance = VortexMath.DistanceKM(node, this);
}
// Select the 25 nearest, then from those select only the ones that are in the 180 degree arc of the direction
// we intend to move in from the startpoint
// todo: make both 25 and 180 parameters
IEnumerable <TaxiNode> selectedNodes = taxiNodes.OrderBy(v => v.TemporaryDistance).Take(25);
fallback = selectedNodes.First();
if (fallback.TemporaryDistance < 0.0025)
{
// There is a atc taxi node really close to the parking, try to build pushback path from there
if (fallback.IncomingEdges.Count == 1)
{
TaxiEdge theEdge = fallback.IncomingEdges.FirstOrDefault();
if (theEdge != null)
{
fallback = theEdge.StartNode;
while (fallback.TemporaryDistance < 0.150 && fallback.IncomingEdges.Count <= 2)
{
TaxiEdge nextEdge = fallback.IncomingEdges.FirstOrDefault(e => e.StartNode != theEdge.EndNode);
if (nextEdge == null)
{
break;
}
// This catches the cases at the end of an apron where the only
// link is the actual taxipath already
if (VortexMath.AbsTurnAngle(theEdge.Bearing, nextEdge.Bearing) > VortexMath.Deg060Rad)
{
break;
}
// todo: each node should be added to the parking as 'push back trajectory'
fallback = nextEdge.StartNode;
theEdge = nextEdge;
}
NearestNode = fallback;
AlternateAfterPushBack = null;
PushBackLatitude = fallback.Latitude;
PushBackLongitude = fallback.Longitude;
return;
}
}
}
selectedNodes = selectedNodes.Where(v => Math.Abs(adjustedBearing - VortexMath.BearingRadians(v, this)) < VortexMath.PI05);
// For each qualifying node
// Todo: check this part for tie downs
foreach (TaxiNode v in selectedNodes)
{
// Look at each link coming into it from other nodes
foreach (TaxiEdge incoming in v.IncomingEdges)
{
double pushBackLatitude = 0;
double pushBackLongitude = 0;
// Now find where the 'start point outgoing line' intersects with the taxi link we are currently checking
if (!VortexMath.Intersection(Latitude, Longitude, adjustedBearing,
incoming.StartNode.Latitude, incoming.StartNode.Longitude, incoming.Bearing,
ref pushBackLatitude, ref pushBackLongitude))
{
// If computation fails, try again but now with the link in the other direction.
// Ignoring one way links here, I just want a push back target for now that's close to A link.
if (!VortexMath.Intersection(Latitude, Longitude, adjustedBearing,
incoming.StartNode.Latitude, incoming.StartNode.Longitude, incoming.Bearing + Math.PI,
ref pushBackLatitude, ref pushBackLongitude))
{
// Lines might be parallel, can't find intersection, skip
continue;
}
}
// Great Circles cross twice, if we found the one on the back of the earth, convert it to the
// one on the airport
// Todo: check might fail for airports on the -180/+180 longitude line
if (Math.Abs(pushBackLongitude - Longitude) > 0.25 * Math.PI)
{
pushBackLatitude = -pushBackLatitude;
pushBackLongitude += VortexMath.PI;
if (pushBackLongitude > VortexMath.PI)
{
pushBackLongitude -= VortexMath.PI2;
}
}
// To find the best spot we must know if the found intersection is actually
// on the link or if it is somewhere outside the actual link. These are
// still usefull in some cases
bool foundTargetIsOutsideSegment = false;
// Todo: check might fail for airports on the -180/+180 longitude line
if (pushBackLatitude - incoming.StartNode.Latitude > 0)
{
if (v.Latitude - pushBackLatitude <= 0)
{
foundTargetIsOutsideSegment = true;
}
}
else if (v.Latitude - pushBackLatitude > 0)
{
foundTargetIsOutsideSegment = true;
}
if (pushBackLongitude - incoming.StartNode.Longitude > 0)
{
if (v.Longitude - pushBackLongitude <= 0)
{
foundTargetIsOutsideSegment = true;
}
}
else if (v.Longitude - pushBackLongitude > 0)
{
foundTargetIsOutsideSegment = true;
}
// Ignore links where the taxiout line intercepts at too sharp of an angle if it is
// also outside the actual link.
// todo: Maybe ignore these links right away, saves a lot of calculations
double interceptAngleSharpness = Math.Abs(VortexMath.PI05 - Math.Abs((adjustedBearing - incoming.Bearing) % Math.PI)) / Math.PI;
if (foundTargetIsOutsideSegment && interceptAngleSharpness > 0.4)
{
continue;
}
// for the found location keep track of the distance to it from the start point
// also keep track of the distances to both nodes of the link we are inspecting now
double pushDistance = 0.0;
double distanceSource = VortexMath.DistancePyth(incoming.StartNode.Latitude, incoming.StartNode.Longitude, pushBackLatitude, pushBackLongitude);
double distanceDest = VortexMath.DistancePyth(v.Latitude, v.Longitude, pushBackLatitude, pushBackLongitude);
// If the found point is outside the link, add the distance to the nearest node of
// the link times 2 as a penalty to the actual distance. This prevents pushback point
// candidates that sneak up on the start because of a slight angle in remote link
// from being accepted as best.
TaxiNode nearestVertexIfPushBackOutsideSegment = null;
if (foundTargetIsOutsideSegment)
{
if (distanceSource < distanceDest)
{
pushDistance = distanceSource * 2.0;
nearestVertexIfPushBackOutsideSegment = incoming.StartNode;
}
else
{
pushDistance = distanceDest * 2.0;
nearestVertexIfPushBackOutsideSegment = v;
}
}
// How far is the candidate from the start point?
pushDistance += VortexMath.DistancePyth(Latitude, Longitude, pushBackLatitude, pushBackLongitude);
// See if it is a better candidate
if (pushDistance < shortestDistance)
{
bestPushBackLatitude = pushBackLatitude;
bestPushBackLongitude = pushBackLongitude;
shortestDistance = pushDistance;
// Setting things up for the path calculation that will follow later
if (foundTargetIsOutsideSegment)
{
// The taxi out route will start with a push to the best candidate
// Then move to the 'firstAfterPush' node and from there follow
// the 'shortest' path to the runway
firstAfterPush = nearestVertexIfPushBackOutsideSegment;
alternateAfterPush = null;
}
else
{
// The taxi out route will start with a push to the best candidate
// Then, if the second node in the find 'shortest' path is the alternate
// the first point will be skipped. If the second point is not the alternate,
// the 'firstAfterPush' will be the first indeed and after that the found
// route will be followed.
if (distanceSource < distanceDest)
{
firstAfterPush = incoming.StartNode;
alternateAfterPush = v;
}
else
{
firstAfterPush = v;
alternateAfterPush = incoming.StartNode;
}
}
}
}
}
// All candiates have been considered, post processing the winner:
if (shortestDistance < double.MaxValue)
{
// If there is one, check if it is not too far away from the start. This catches cases where
// a gate at the end of an apron with heading parallel to the apron entry would get a best
// target on the taxiway outside the apron.
double actualDistance = VortexMath.DistanceKM(Latitude, Longitude, bestPushBackLatitude, bestPushBackLongitude);
if (actualDistance > 0.25)
{
// Fix this by pushing to the end point of the entry link
// (If that is actually the nearest node to the parking, but alas...
// this is the default WT3 behaviour anyway)
NearestNode = selectedNodes.First();
AlternateAfterPushBack = null;
PushBackLatitude = NearestNode.Latitude;
PushBackLongitude = NearestNode.Longitude;
}
else
{
// Store the results in the startpoint
PushBackLatitude = bestPushBackLatitude;
PushBackLongitude = bestPushBackLongitude;
NearestNode = firstAfterPush;
AlternateAfterPushBack = alternateAfterPush;
}
}
else
{
// Crude fallback to defautl WT behavoit if nothing was found.
NearestNode = fallback;
AlternateAfterPushBack = null;
PushBackLatitude = NearestNode.Latitude;
PushBackLongitude = NearestNode.Longitude;
}
}
private void ReadTaxiEdge(string line)
{
string[] tokens = line.Split(_splitters, StringSplitOptions.RemoveEmptyEntries);
uint va = uint.Parse(tokens[1]);
uint vb = uint.Parse(tokens[2]);
bool isRunway = (tokens[4][0] != 't'); // taxiway_X or runway
bool isTwoWay = (tokens[3][0] == 't'); // oneway or twoway
XPlaneAircraftCategory maxSize;
if (isRunway || tokens[4].Length < 9)
{
maxSize = (XPlaneAircraftCategory.Max - 1);
}
else
{
maxSize = (XPlaneAircraftCategory)(tokens[4][8] - 'A');
}
string linkName = tokens.Length > 5 ? string.Join(" ", tokens.Skip(5)) : "";
TaxiNode startNode = _nodeDict[va];
TaxiNode endNode = _nodeDict[vb];
TaxiEdge outgoingEdge = _edges.SingleOrDefault(e => (e.StartNode.Id == va && e.EndNode.Id == vb));
if (outgoingEdge != null)
{
// todo: report warning
outgoingEdge.MaxCategory = (XPlaneAircraftCategory)Math.Max((int)outgoingEdge.MaxCategory, (int)maxSize);
}
else
{
outgoingEdge = new TaxiEdge(startNode, endNode, isRunway, maxSize, linkName);
_edges.Add(outgoingEdge);
}
TaxiEdge incomingEdge = null;
if (isTwoWay)
{
incomingEdge = _edges.SingleOrDefault(e => (e.StartNode.Id == vb && e.EndNode.Id == va));
if (incomingEdge != null)
{
// todo: report warning
incomingEdge.MaxCategory = (XPlaneAircraftCategory)Math.Max((int)incomingEdge.MaxCategory, (int)maxSize);
}
else
{
incomingEdge = new TaxiEdge(endNode, startNode, isRunway, maxSize, linkName);
_edges.Add(incomingEdge);
incomingEdge.ReverseEdge = outgoingEdge;
outgoingEdge.ReverseEdge = incomingEdge;
}
}
endNode.AddEdgeFrom(outgoingEdge);
if (isTwoWay)
{
startNode.AddEdgeFrom(incomingEdge);
}
}
public void AddEdgeFrom(TaxiEdge edge)
{
IncomingEdges.Add(edge);
}