/// <summary>
/// Aggregates a route by remove information useless to the generation of routing instructions.
/// </summary>
/// <param name="route"></param>
/// <returns></returns>
public AggregatedPoint Aggregate(Route route)
{
// create the enumerator.
var enumerator = new AggregatedPointEnumerator(route);
AggregatedRoutePoint previous = null;
AggregatedRoutePoint current = null;
AggregatedRoutePoint next = null;
AggregatedPoint previousPoint = null;
AggregatedArc previousArc = null;
AggregatedPoint p = null;
// loop over all aggregated points.
while (enumerator.MoveNext())
{
// get the next point.
next = enumerator.Current;
// process
this.Process(route, previous, current, next, ref p, ref previousArc, ref previousPoint);
// make the next, current and the current previous.
previous = current;
current = next;
next = null;
}
// process once more, the current current has not been processed.
this.Process(route, previous, current, next, ref p, ref previousArc, ref previousPoint);
return(p);
}
/// <summary>
/// Processes a part of the route.
/// </summary>
private void Process(Route route, AggregatedRoutePoint previous, AggregatedRoutePoint current,
AggregatedRoutePoint next, ref AggregatedPoint p, ref AggregatedArc previousArc, ref AggregatedPoint previousPoint)
{
// process the current point.
if (current != null)
{
if (previous == null)
{ // point is always significant, it is the starting point!
// create point.
p = new AggregatedPoint();
p.Angle = null;
p.ArcsNotTaken = null;
p.Location = new GeoCoordinate(current.Segment.Latitude, current.Segment.Longitude);
p.Points = new List <PointPoi>();
p.SegmentIdx = current.SegmentIndex;
if (current.Segment.Points != null)
{
foreach (var routePoint in current.Segment.Points)
{
var poi = new PointPoi();
poi.Name = routePoint.Name;
poi.Tags = routePoint.Tags.ConvertTo();
poi.Location = new GeoCoordinate(routePoint.Latitude, routePoint.Longitude);
poi.Angle = null; // there is no previous point; no angle is specified.
p.Points.Add(poi);
}
}
previousPoint = p;
}
else
{ // test if point is significant.
var nextArc = this.CreateArcAndPoint(route, previous, current, next);
// test if the next point is significant.
if (previousArc == null)
{ // this arc is always significant; it is the first arc.
previousPoint.Next = nextArc;
previousArc = nextArc;
}
else
{ // there is a previous arc; a test can be done if the current point is significant.
if (this.IsSignificant(previousArc, nextArc))
{ // the arc is significant; append it to the previous arc.
previousArc.Next.Next = nextArc;
previousArc = nextArc;
previousPoint = nextArc.Next;
}
else
{ // if the arc is not significant compared to the previous one, the previous one can extend until the next point.
// THIS IS THE AGGREGATION STEP!
// add distance.
var distanceToNext = previousArc.Next.Location.DistanceReal(nextArc.Next.Location);
previousArc.Distance = previousArc.Distance + distanceToNext;
// set point.
previousArc.Next = nextArc.Next;
}
}
}
}
}
/// <summary>
/// Generates an arc and it's next point from the current aggregated point.
/// </summary>
/// <param name="route"></param>
/// <param name="previous"></param>
/// <param name="current"></param>
/// <param name="next"></param>
/// <returns></returns>
internal AggregatedArc CreateArcAndPoint(Route route, AggregatedRoutePoint previous,
AggregatedRoutePoint current, AggregatedRoutePoint next)
{
// create the arc.
var a = new AggregatedArc();
a.Name = current.Segment.Name;
a.Names = current.Segment.Names.ConvertTo();
a.Tags = current.Segment.Tags.ConvertToTagsCollection();
a.Vehicle = string.IsNullOrWhiteSpace(route.Vehicle) ? current.Segment.Vehicle : route.Vehicle;
if (previous != null)
{
var previousCoordinate = new GeoCoordinate(previous.Segment.Latitude, previous.Segment.Longitude);
var currentCoordinate = new GeoCoordinate(current.Segment.Latitude, current.Segment.Longitude);
var distance = previousCoordinate.DistanceReal(currentCoordinate);
a.Distance = distance;
}
// create the point.
var p = new AggregatedPoint();
p.Location = new GeoCoordinate(current.Segment.Latitude, current.Segment.Longitude);
p.Points = new List <PointPoi>();
p.SegmentIdx = current.SegmentIndex;
if (previous != null && next != null && next.Segment != null)
{
var previousCoordinate = new GeoCoordinate(previous.Segment.Latitude, previous.Segment.Longitude);
var nextCoordinate = new GeoCoordinate(next.Segment.Latitude, next.Segment.Longitude);
p.Angle = RelativeDirectionCalculator.Calculate(previousCoordinate, p.Location, nextCoordinate);
}
if (current.Segment.SideStreets != null && current.Segment.SideStreets.Length > 0)
{
p.ArcsNotTaken = new List <KeyValuePair <RelativeDirection, AggregatedArc> >();
foreach (var sideStreet in current.Segment.SideStreets)
{
var side = new AggregatedArc();
side.Name = sideStreet.Name;
side.Names = sideStreet.Names.ConvertTo();
side.Tags = sideStreet.Tags.ConvertToTagsCollection();
RelativeDirection sideDirection = null;
if (previous != null)
{
var previousCoordinate = new GeoCoordinate(previous.Segment.Latitude, previous.Segment.Longitude);
var nextCoordinate = new GeoCoordinate(sideStreet.Latitude, sideStreet.Longitude);
sideDirection = RelativeDirectionCalculator.Calculate(previousCoordinate, p.Location, nextCoordinate);
}
p.ArcsNotTaken.Add(new KeyValuePair <RelativeDirection, AggregatedArc>(sideDirection, side));
}
}
if (current.Segment.Points != null)
{
foreach (var routePoint in current.Segment.Points)
{
var poi = new PointPoi();
poi.Name = routePoint.Name;
poi.Tags = routePoint.Tags.ConvertTo();
poi.Location = new GeoCoordinate(routePoint.Latitude, routePoint.Longitude);
var previousCoordinate = new GeoCoordinate(previous.Segment.Latitude, previous.Segment.Longitude);
var currentCoordinate = new GeoCoordinate(current.Segment.Latitude, current.Segment.Longitude);
poi.Angle = RelativeDirectionCalculator.Calculate(previousCoordinate, currentCoordinate, poi.Location);
p.Points.Add(poi);
}
}
// link the arc to the point.
a.Next = p;
return(a);
}