public static SpatialHashSearcher <SegmentIndex> CreateSpatialSearcher(
MultiLinestring multiLinestring, double?knownAverageSegmentLength = null)
{
if (multiLinestring.SegmentCount < _segmentCountThreshold)
{
return(null);
}
double gridSize;
if (knownAverageSegmentLength != null)
{
gridSize = EstimateOptimalGridSize(knownAverageSegmentLength.Value);
}
else
{
gridSize =
multiLinestring.SegmentCount > 0
? EstimateOptimalGridSize(multiLinestring.GetLinestrings())
: 100;
}
var result = new SpatialHashSearcher <SegmentIndex>(
multiLinestring.XMin, multiLinestring.YMin,
gridSize, multiLinestring.SegmentCount, 5);
Populate(result, multiLinestring);
return(result);
}
private static void Populate(SpatialHashSearcher <int> spatialSearcher,
Linestring linestring)
{
for (var i = 0; i < linestring.SegmentCount; i++)
{
Line3D line = linestring[i];
spatialSearcher.Add(i, line.XMin, line.YMin, line.XMax, line.YMax);
}
}
private static void Populate(SpatialHashSearcher <int> spatialSearcher,
IPointList pointList)
{
for (var i = 0; i < pointList.PointCount; i++)
{
IPnt pnt = pointList.GetPoint(i);
spatialSearcher.Add(i, pnt.X, pnt.Y, pnt.X, pnt.Y);
}
}
public static SpatialHashSearcher <int> CreateSpatialSearcher(
Linestring forLinestring, double gridSize)
{
var result = new SpatialHashSearcher <int>(
forLinestring.XMin, forLinestring.YMin,
gridSize, forLinestring.SegmentCount, 5);
Populate(result, forLinestring);
return(result);
}
public static SpatialHashSearcher <int> CreateSpatialSearcher <TP>(
Multipoint <TP> multipoint, double gridSize) where TP : IPnt
{
var result = new SpatialHashSearcher <int>(
multipoint.XMin, multipoint.YMin,
gridSize, multipoint.PointCount, 5);
Populate(result, multipoint);
return(result);
}
public static SpatialHashSearcher <T> CreateSpatialSearcher(
[NotNull] IList <T> values,
Func <T, EnvelopeXY> getBoundsFunc,
double gridSize = double.NaN)
{
Assert.ArgumentCondition(values.Count > 0, "Empty value list");
List <EnvelopeXY> valueEnvelopes =
values.Select(getBoundsFunc).ToList();
EnvelopeXY fullExtent;
double averageEnvLateralLength;
GetEnvelopeStatistics(valueEnvelopes, out fullExtent,
out averageEnvLateralLength);
if (double.IsNaN(averageEnvLateralLength))
{
if (double.IsNaN(gridSize))
{
throw new ArgumentException(
"Cannot derive grid size from values, please provide a grid size > 0.");
}
averageEnvLateralLength = gridSize;
}
Assert.NotNull(fullExtent);
double maxTileCount = (fullExtent.Width * fullExtent.Height) /
(averageEnvLateralLength * averageEnvLateralLength);
if (double.IsNaN(gridSize))
{
gridSize = averageEnvLateralLength * 2;
}
double estimatedItemsPerTile = maxTileCount / values.Count;
var result =
new SpatialHashSearcher <T>(
fullExtent.XMin, fullExtent.YMin, gridSize, (int)maxTileCount,
estimatedItemsPerTile);
// populate
for (int i = 0; i < values.Count; i++)
{
result.Add(values[i], valueEnvelopes[i]);
}
return(result);
}
public static SpatialHashSearcher <SegmentIndex> CreateSpatialSearcher(
MultiLinestring multiLinestring, double gridSize)
{
if (multiLinestring.SegmentCount < _segmentCountThreshold)
{
return(null);
}
var result = new SpatialHashSearcher <SegmentIndex>(
multiLinestring.XMin, multiLinestring.YMin,
gridSize, multiLinestring.SegmentCount, 5);
Populate(result, multiLinestring);
return(result);
}
private static void Populate(
SpatialHashSearcher <SegmentIndex> spatialSearcher,
MultiLinestring multiLinestring)
{
for (int i = 0; i < multiLinestring.Count; i++)
{
var linestring = multiLinestring.GetLinestring(i);
for (var j = 0; j < linestring.SegmentCount; j++)
{
Line3D line = linestring[j];
spatialSearcher.Add(new SegmentIndex(i, j),
line.XMin, line.YMin, line.XMax, line.YMax);
}
}
}
