/// <summary>
/// Finds all candidates points for given GPS track point
/// </summary>
/// <param name="gpxPt">GPS point</param>
/// <returns>Collection of points candidate points on road segments</returns>
public IEnumerable<CandidatePoint> FindCandidatePoints(GPXPoint gpxPt)
{
List<CandidatePoint> result = new List<CandidatePoint>();
BBox gpxBbox = new BBox(new IPointGeo[] { gpxPt });
gpxBbox.Inflate(0.0007, 0.0011);
foreach (var road in _trackCutout) {
if (Topology.Intersects(gpxBbox, road.BBox)) {
Segment<IPointGeo> roadSegment;
IPointGeo projectedPoint = Topology.ProjectPoint(gpxPt, road, out roadSegment);
result.Add(new CandidatePoint() { MapPoint = projectedPoint,
Road = road, RoadSegment = roadSegment,
ObservationProbability = CalculateObservationProbability(gpxPt, projectedPoint) });
}
}
if (result.Count == 0) {
throw new Exception(string.Format("Can not find any candidate point for {0}", gpxPt));
}
return result;
}
void CreateTrackCutout(GPXTrackSegment track)
{
_trackCutout.Clear();
BBox trackBBox = new BBox();
foreach (var point in track.Nodes) {
trackBBox.ExtendToCover(point);
}
trackBBox.Inflate(0.0015, 0.0015);
foreach (var road in _graph.ConnectionGeometries) {
if (Topology.Intersects(road.BBox, trackBBox)) {
_trackCutout.Add(road);
}
}
}
public void BBoxInflateIncreasesBBoxSize()
{
PointGeo p1 = new PointGeo(1, 0);
PointGeo p2 = new PointGeo(0, 1);
BBox target = new BBox(new IPointGeo[] { p1, p2 });
target.Inflate(0.1, 0.2);
Assert.Equal(1.1, target.North);
Assert.Equal(-0.1, target.South);
Assert.Equal(1.2, target.East);
Assert.Equal(-0.2, target.West);
}