public void CanMaintainDirtyFlag()
{
var qt = new PointQuadtree <int>();
// New empty inverted index isn't dirty:
Assert.False(qt.IsDirty);
qt.Add(0, new Point(0, 0));
// After adding an item, it's dirty:
Assert.True(qt.IsDirty);
qt.Build();
// After building, the index is clean:
Assert.False(qt.IsDirty);
qt.Add(1, new Point(1, 1));
// After adding items, index is dirty:
Assert.True(qt.IsDirty);
qt.Clear();
// After clearing, index is empty and thus clean:
Assert.False(qt.IsDirty);
}
public void CanBoundingBox()
{
var qt = new PointQuadtree <int>();
Assert.False(qt.IsDirty);
Assert.Equal(0, qt.ItemCount);
Assert.Null(qt.BoundingBox);
qt.Add(33, new Point(3, 3));
qt.Build();
Assert.NotNull(qt.BoundingBox);
Assert.Equal(new Envelope(3, 3, 3, 3), qt.BoundingBox);
qt.Add(55, new Point(5, 5));
qt.Build();
Assert.NotNull(qt.BoundingBox);
Assert.Equal(new Envelope(3, 3, 5, 5), qt.BoundingBox);
qt.Clear();
Assert.False(qt.IsDirty);
Assert.Null(qt.BoundingBox);
}
private void ShowStats <T>(PointQuadtree <T> qt)
{
if (qt.IsDirty)
{
qt.Build();
}
_output.WriteLine($"Items: {qt.ItemCount}, Depth: {qt.MeanDepth} mean {qt.MaxDepth} max");
}
private static string GetSerializedQuadtree(PointQuadtree <Place> qt)
{
var buffer = new StringBuilder();
using (var writer = new StringWriter(buffer))
{
qt.Dump(writer);
}
return(buffer.ToString());
}
private static PointQuadtree <Place> GetSampleDataset()
{
var quadtree = new PointQuadtree <Place>();
quadtree.Add(Chicago, Chicago.Point);
quadtree.Add(Mobile, Mobile.Point);
quadtree.Add(Toronto, Toronto.Point);
quadtree.Add(Buffalo, Buffalo.Point);
quadtree.Add(Denver, Denver.Point);
quadtree.Add(Omaha, Omaha.Point);
quadtree.Add(Atlanta, Atlanta.Point);
quadtree.Add(Miami, Miami.Point);
// don't add Memphis
quadtree.Build();
return(quadtree);
}
private static PointQuadtree <Place> GetGlobalDataset()
{
var places = new[]
{
FernsehturmBerlin, ElizabethTowerLondon, NotreDameTourNord, NotreDameTourSud,
EiffelTower, EsriRedlands, LadyLiberty, SydneyOpera, Anadyr, Josefstrasse21,
Josefstrasse211, Josefstrasse212, Josefstrasse214, Josefstrasse216,
Josefstrasse218, KigaliAirport, StMatthewIsland, Longyearbyen
};
var quadtree = new PointQuadtree <Place>();
foreach (var place in places)
{
quadtree.Add(place, place.Point);
}
quadtree.Build();
return(quadtree);
}
public void LargeQuadtreeTest()
{
const int numPoints = 1000000;
var random = new Random();
var timer = new Stopwatch();
// Build quadtree with numPoints points having
// random x and y coordinates in the real interval:
timer.Start();
var qt = new PointQuadtree <int>();
for (int id = 0; id < numPoints; id++)
{
double x = 100 * random.NextDouble();
double y = 100 * random.NextDouble();
qt.Add(id, new Point(x, y));
}
timer.Stop();
_output.WriteLine("Built QT with {0:N0} random points in {1}",
numPoints, timer.Elapsed);
timer.Reset();
timer.Start();
var r1 = new List <int>();
int c1 = qt.Query(new Envelope(0, 0, 100, 100), null, r1);
Assert.Equal(numPoints, c1);
Assert.Equal(numPoints, r1.Count);
timer.Stop();
_output.WriteLine("Queried world rectangle in {0}", timer.Elapsed);
timer.Reset();
timer.Start();
int c2 = qt.Count(new Envelope(0, 0, 100, 100), null);
Assert.Equal(numPoints, c2);
timer.Stop();
_output.WriteLine("Counted world rectangle in {0}", timer.Elapsed);
timer.Reset();
timer.Start();
var r3 = new List <int>();
int c3 = qt.Query(new Envelope(0, 0, 50, 50), null, r3);
Assert.True(r3.Count == c3);
timer.Stop();
_output.WriteLine("Queried SW quadrant ({0} points) in {1}",
c3, timer.Elapsed);
timer.Reset();
timer.Start();
int c4 = qt.Count(new Envelope(0, 0, 50, 50), null);
timer.Stop();
_output.WriteLine("Counted SW quadrant ({0} points) in {1}",
c4, timer.Elapsed);
ShowStats(qt);
}
public void CanHandleCoincidentPoints()
{
var qt = new PointQuadtree <Place>();
qt.Add(Chicago, Chicago.Point);
qt.Add(Chicago, Chicago.Point); // again
string serializedQuadtree = GetSerializedQuadtree(qt);
Assert.Equal("(Chicago (Chicago ....)...)", serializedQuadtree);
var r1 = new List <Place>();
int c1 = qt.Query(new Envelope(0, 0, 100, 100), null, r1);
Assert.Equal(2, c1);
Assert.Equal(r1.OrderBy(p => p.Tag), Seq(Chicago, Chicago));
var r2 = new List <Place>();
int c2 = qt.Query(new Envelope(Chicago.Point, Chicago.Point), null, r2);
Assert.Equal(2, c2);
Assert.Equal(r2.OrderBy(p => p.Tag), Seq(Chicago, Chicago));
qt.Add(Mobile, Mobile.Point);
qt.Add(Mobile, Mobile.Point); // again
var r3 = new List <Place>();
int c3 = qt.Query(new Envelope(Mobile.Point, Mobile.Point), null, r3);
Assert.Equal(2, c3);
Assert.Equal(r3.OrderBy(p => p.Tag), Seq(Mobile, Mobile));
var r4 = new List <Place>();
int c4 = qt.Query(new Envelope(Chicago.Point, Mobile.Point), null, r4);
Assert.Equal(4, c4);
Assert.Equal(r4.OrderBy(p => p.Tag), Seq(Chicago, Chicago, Mobile, Mobile));
serializedQuadtree = GetSerializedQuadtree(qt);
Assert.Equal("(Chicago (Chicago ....)..(Mobile (Mobile ....)...))", serializedQuadtree);
qt.Add(Toronto, Toronto.Point);
qt.Add(Buffalo, Buffalo.Point);
qt.Add(Denver, Denver.Point);
qt.Add(Omaha, Omaha.Point);
qt.Add(Atlanta, Atlanta.Point);
qt.Add(Miami, Miami.Point);
qt.Add(Memphis, Memphis.Point);
qt.Add(Memphis, Memphis.Point); // again
serializedQuadtree = GetSerializedQuadtree(qt);
Assert.Equal(
"(Chicago (Chicago (Toronto ...(Buffalo ....))...)(Denver ....)(Omaha ....)(Mobile (Mobile (Atlanta ....)...)(Memphis (Memphis ....)...).(Miami ....)))",
serializedQuadtree);
var r5 = new List <Place>();
int c5 = qt.Query(new Envelope(30, 5, 60, 25), null, r5);
Assert.Equal(4, c5);
Assert.Equal(r5.OrderBy(p => p.Tag), Seq(Memphis, Memphis, Mobile, Mobile));
ShowStats(qt);
}
