private Trajectory2D GetSubTrajectory(Trajectory2D trajectory, int start, int end, int downSampleAmount)
{
var newTrajectory = new Trajectory2D();
var originalCount = end - start + 1;
for (var i = 0; i <= downSampleAmount - 1; i++)
{
var offset = (int)Math.Floor(((double)(((long)i) * (originalCount - 1))) / (downSampleAmount - 1));
var newPoint = trajectory[start - 1 + offset];
newTrajectory.AppendPoint(newPoint.X, newPoint.Y);
}
return(newTrajectory);
}
public override void Compute(MSInput input, out MSOutput output)
{
output = new MSOutput();
var trajectory = input.Trajectory;
List <TPoint2D> prevApproximation = null;
for (var level = input.NumLevels; level >= 1; level--)
{
var epsilon = input.GetEpsilon(level);
List <TPoint2D> approximation;
if (prevApproximation == null)
{
approximation = Approximator.Approximate(trajectory, epsilon);
}
else
{
approximation = new List <TPoint2D>();
var prevPoint = trajectory.First();
for (var i = 1; i < prevApproximation.Count; i++)
{
var point = prevApproximation[i];
//excludes the end point
var subApproximation = Approximator.Approximate(trajectory, prevPoint.Index, point.Index, epsilon);
approximation.AddRange(subApproximation);
prevPoint = point;
}
approximation.Add(trajectory.Last());
}
var newTrajectory = new Trajectory2D();
foreach (var point in approximation)
{
newTrajectory.AppendPoint(point.X, point.Y);
}
//report shortest path
//output.LogObject("Level Shortest Path", levelTrajectory);
output.LogLine("Level " + level + " trajectory found. Length: " + newTrajectory.Count);
output.SetTrajectoryAtLevel(level, newTrajectory);
prevApproximation = approximation;
}
}
public override void Compute(MSInput input, out MSOutput output)
{
//output = new MSOutput();
output = new Output();
var trajectory = input.Trajectory;
ShortcutProvider.Init(input, output, true);
var shortcutGraphs = ((Output)output).Graphs;
//var shortcutGraphs = new Dictionary<int, ShortcutGraph>();
ShortcutGraph prevShortcutGraph = null;
for (var level = 1; level <= input.NumLevels; level++)
{
var epsilon = input.GetEpsilon(level);
ShortcutGraph shortcutGraph;
if (prevShortcutGraph != null)
{
//clone graph from previous level
shortcutGraph = (ShortcutGraph)prevShortcutGraph.Clone();
}
else
{
//build initial graph (just a simple sequence of nodes like in the trajectory)
shortcutGraph = new ShortcutGraph(trajectory);
}
//select correct shortcuts
var shortcutsLevel = ShortcutProvider.GetShortcuts(level, epsilon);
//output.LogObject("Number of shortcuts found for level " + level, () => shortcutsLevel.Count);
if (level == 1)
{
foreach (var shortcut in shortcutsLevel)
{
shortcutGraph.AddShortcut(shortcut);
}
}
else
{
var weights = new Dictionary <Shortcut, int>();
var shortcutWeights = GetShortcutWeights(shortcutGraph, shortcutsLevel);
foreach (var pair in shortcutWeights)
{
var shortcut = pair.Key;
var weight = pair.Value;
weights[shortcut] = weight;
}
foreach (var shortcut in shortcutsLevel)
{
shortcutGraph.AddShortcut(shortcut, weights[shortcut]);
}
//increment weights of all edges by 1
shortcutGraph.IncrementAllWeights();
}
//output.LogObject("Shortcut Graph", shortcutGraph);
shortcutGraphs[level] = shortcutGraph;
prevShortcutGraph = shortcutGraph;
}
output.LogLine("Shortcut graph size at scale m: " + shortcutGraphs[input.NumLevels].Count);
output.LogLine("Average amount of shortcuts handled per scale: " + shortcutGraphs[input.NumLevels].Count / input.NumLevels);
output.LogLine("");
output.LogLine("Starting calculations of level trajectories bottom-up");
output.LogLine("");
//bottom up calculation of level trajectories
LinkedList <TPoint2D> prevShortestPath = null;
for (var level = input.NumLevels; level >= 1; level--)
{
var shortcutGraph = shortcutGraphs[level];
LinkedList <TPoint2D> shortestPath;
if (prevShortestPath == null)
{
var pointPath = ShortestPathProvider.FindShortestPath(shortcutGraph, trajectory.First(), trajectory.Last());
shortestPath = pointPath.Points;
}
else
{
shortestPath = new LinkedList <TPoint2D>();
var prevPoint = trajectory.First();
foreach (var point in prevShortestPath)
{
var pointPath = ShortestPathProvider.FindShortestPath(shortcutGraph, prevPoint, point);
foreach (var p in pointPath.Points)
{
shortestPath.AddLast(p);
}
prevPoint = point;
}
}
var newTrajectory = new Trajectory2D();
newTrajectory.AppendPoint(trajectory.First().X, trajectory.First().Y);
foreach (var point in shortestPath)
{
newTrajectory.AppendPoint(point.X, point.Y);
}
//report shortest path
//output.LogObject("Level Shortest Path", levelTrajectory);
output.LogLine("Level " + level + " trajectory found. Length: " + newTrajectory.Count);
output.SetTrajectoryAtLevel(level, newTrajectory);
prevShortestPath = shortestPath;
}
}
