/// <summary>
/// Converts a collection of geometric shapes on the surface of the ellipsoid
/// to the collection of geometric figures in the plane in line with the given projection.
/// </summary>
/// <param name="geometries">Enumerator geometric shapes on the surface of the ellipsoid</param>
/// <param name="projection">Projection</param>
/// <returns>Collection of geometric figures in the plane</returns>
public static GeographyCollection GetGeographies(IEnumerable <IGeometry> geometries, GnomonicProjection projection)
{
GeographyCollection result = new GeographyCollection();
IGeography geometry = null;
foreach (IGeometry g in geometries)
{
if (g is PointD)
{
geometry = unprojectPoint((PointD)g, projection);
}
else if (g is Polyline)
{
geometry = unprojectPolyline((Polyline)g, projection);
}
else if (g is Polygon)
{
geometry = unprojectPolygon((Polygon)g, projection);
}
else if (g is MultiPoint)
{
geometry = unprojectMultiPoint((MultiPoint)g, projection);
}
else
{
throw new NotImplementedException("Geometry \"" + g.GetType().FullName + "\" is not supported.");
}
result.Add(geometry);
}
return(result);
}
private ICollection <IGeography> calculateOverlay(IGeography geometry1, IGeography geometry2, OverlayType operation, bool p)
{
GeographyCollection egc = new GeographyCollection();
egc.Add(geometry1);
egc.Add(geometry2);
GnomonicProjection projection = GeometrySpreader.GetProjection(egc);
GeometryCollection gc = GeometrySpreader.GetGeometries(egc, projection);
OverlayCalculator oc = new OverlayCalculator();
ICollection <IGeometry> planarResult = oc.CalculateOverlay(gc[0], gc[1], operation);
egc = GeometrySpreader.GetGeographies(planarResult, projection);
return(egc);
}
private static Polygon getBoundsBuffer(GeoPolygon polygon, GnomonicProjection projection, double distance, int pointsPerCircle, bool allowParallels)
{
Polygon temp = new Polygon();
List <Polygon> partialBuffers = new List <Polygon>();
GeographyCollection geographyCollection = new GeographyCollection();
ICollection <IGeometry> unionResult = null;
int c = 0;
foreach (GeoContour contour in polygon.Contours)
{
for (int i = 0; i < contour.Vertices.Count; i++)
{
GeoPoint p = contour.Vertices[i];
GeoPolygon tempPolygon = getPointBuffer(p, Math.Abs(distance), pointsPerCircle);
geographyCollection.Clear();
geographyCollection.Add(tempPolygon);
GeometryCollection gc = GeometrySpreader.GetGeometries(geographyCollection, projection);
if (gc[0] is Polygon)
{
unionResult = temp.Union((Polygon)gc[0]);
}
if (unionResult.Count > 0)
{
temp = (Polygon)((GeometryCollection)unionResult)[0];
}
c++;
if (c == 3)
{
partialBuffers.Add(temp);
temp = new Polygon();
c = 0;
}
}
}
if (temp.CoordinateCount > 0)
{
partialBuffers.Add(temp);
}
return(mergePartialBuffers(partialBuffers, allowParallels));
}
private static void projectGeography(IGeography geography, out GnomonicProjection projection, out IGeometry geometry)
{
GeographyCollection geographyCollection = new GeographyCollection();
geographyCollection.Add(geography);
double centerLatitude, centerLongitude;
GnomonicProjection.GetCenter(geography.ExtractPoints(), out centerLatitude, out centerLongitude);
projection = new GnomonicProjection(centerLongitude, centerLatitude);
GeometryCollection geometryCollection = GeometrySpreader.GetGeometries(geographyCollection, projection);
if (geometryCollection.Count > 0)
{
geometry = geometryCollection[0];
}
else
{
geometry = null;
}
}
/// <summary>
/// Computes a convex hull of the specified points.
/// </summary>
/// <param name="points">Enumerator of coordinates for which convex hull should be computed</param>
/// <returns>A list containing a sequence of the convex hull points</returns>
public static IList <GeoPoint> GetConvexHull(IEnumerable <GeoPoint> points)
{
GeographyCollection geographyCollection = new GeographyCollection();
foreach (GeoPoint p in points)
{
geographyCollection.Add(p);
}
GnomonicProjection projection = GeometrySpreader.GetProjection(geographyCollection);
GeometryCollection geometryCollection = GeometrySpreader.GetGeometries(geographyCollection, projection);
List <ICoordinate> list = new List <ICoordinate>();
foreach (IGeometry g in geometryCollection)
{
list.Add(((PointD)g).Coordinate);
}
IList <ICoordinate> planarResult = PlanimetryAlgorithms.GetConvexHull(list);
geometryCollection.Clear();
foreach (ICoordinate p in planarResult)
{
geometryCollection.Add(new PointD(p));
}
geographyCollection = GeometrySpreader.GetGeographies(geometryCollection, projection);
List <GeoPoint> result = new List <GeoPoint>();
foreach (GeoPoint p in geographyCollection)
{
result.Add(p);
}
return(result);
}
private static GeoPolygon getPolylineBuffer(GeoPolyline geoPolyline, double angleDistance, int pointsPerCircle, bool allowParallels)
{
geoPolyline = (GeoPolyline)geoPolyline.Clone();
double minAngle = Math.Sin(Math.Abs(angleDistance)) * Math.Sin(Math.PI / pointsPerCircle);
geoPolyline.ReduceSegments(minAngle);
geoPolyline.Densify(minAngle);
GnomonicProjection projection;
IGeometry geometry;
projectGeography(geoPolyline, out projection, out geometry);
Polyline planePolyline = (Polyline)geometry;
GeographyCollection geographyCollection = new GeographyCollection();
Polygon temp = new Polygon();
List <Polygon> partialBuffers = new List <Polygon>();
ICollection <IGeometry> unionResult = null;
int c = 0;
foreach (GeoPath path in geoPolyline.Paths)
{
for (int i = 0; i < path.Vertices.Count - 1; i++)
{
GeoPoint p = path.Vertices[i];
GeoPolygon tempPolygon = getPointBuffer(p, angleDistance, pointsPerCircle);
geographyCollection.Clear();
geographyCollection.Add(tempPolygon);
GeometryCollection gc = GeometrySpreader.GetGeometries(geographyCollection, projection);
if (gc[0] is Polygon)
{
unionResult = temp.Union((Polygon)gc[0]);
}
if (unionResult.Count > 0)
{
temp = (Polygon)((GeometryCollection)unionResult)[0];
}
c++;
if (c == 3)
{
partialBuffers.Add(temp);
temp = new Polygon();
c = 0;
}
}
}
if (temp.CoordinateCount > 0)
{
partialBuffers.Add(temp);
}
Polygon planeBuffer = mergePartialBuffers(partialBuffers, allowParallels);
GeometryCollection geometryCollection = new GeometryCollection();
geometryCollection.Add(planeBuffer);
geographyCollection = GeometrySpreader.GetGeographies(geometryCollection, projection);
foreach (IGeography g in geographyCollection)
{
if (g is GeoPolygon)
{
return((GeoPolygon)g);
}
}
return(new GeoPolygon());
}
/// <summary>
/// Computes a convex hull of the specified points.
/// </summary>
/// <param name="points">Enumerator of coordinates for which convex hull should be computed</param>
/// <returns>A list containing a sequence of the convex hull points</returns>
public static IList<GeoPoint> GetConvexHull(IEnumerable<GeoPoint> points)
{
GeographyCollection geographyCollection = new GeographyCollection();
foreach (GeoPoint p in points)
geographyCollection.Add(p);
GnomonicProjection projection = GeometrySpreader.GetProjection(geographyCollection);
GeometryCollection geometryCollection = GeometrySpreader.GetGeometries(geographyCollection, projection);
List<ICoordinate> list = new List<ICoordinate>();
foreach(IGeometry g in geometryCollection)
list.Add(((PointD)g).Coordinate);
IList<ICoordinate> planarResult = PlanimetryAlgorithms.GetConvexHull(list);
geometryCollection.Clear();
foreach (ICoordinate p in planarResult)
geometryCollection.Add(new PointD(p));
geographyCollection = GeometrySpreader.GetGeographies(geometryCollection, projection);
List<GeoPoint> result = new List<GeoPoint>();
foreach (GeoPoint p in geographyCollection)
result.Add(p);
return result;
}
/// <summary>
/// Converts a collection of geometric shapes on the surface of the ellipsoid
/// to the collection of geometric figures in the plane in line with the given projection.
/// </summary>
/// <param name="geometries">Enumerator geometric shapes on the surface of the ellipsoid</param>
/// <param name="projection">Projection</param>
/// <returns>Collection of geometric figures in the plane</returns>
public static GeographyCollection GetGeographies(IEnumerable<IGeometry> geometries, GnomonicProjection projection)
{
GeographyCollection result = new GeographyCollection();
IGeography geometry = null;
foreach (IGeometry g in geometries)
{
if (g is PointD)
{
geometry = unprojectPoint((PointD)g, projection);
}
else if (g is Polyline)
{
geometry = unprojectPolyline((Polyline)g, projection);
}
else if (g is Polygon)
{
geometry = unprojectPolygon((Polygon)g, projection);
}
else if (g is MultiPoint)
{
geometry = unprojectMultiPoint((MultiPoint)g, projection);
}
else
throw new NotImplementedException("Geometry \"" + g.GetType().FullName + "\" is not supported.");
result.Add(geometry);
}
return result;
}
private ICollection<IGeography> calculateOverlay(IGeography geometry1, IGeography geometry2, OverlayType operation, bool p)
{
GeographyCollection egc = new GeographyCollection();
egc.Add(geometry1);
egc.Add(geometry2);
GnomonicProjection projection = GeometrySpreader.GetProjection(egc);
GeometryCollection gc = GeometrySpreader.GetGeometries(egc, projection);
OverlayCalculator oc = new OverlayCalculator();
ICollection<IGeometry> planarResult = oc.CalculateOverlay(gc[0], gc[1], operation);
egc = GeometrySpreader.GetGeographies(planarResult, projection);
return egc;
}
private static GeoPolygon getPolylineBuffer(GeoPolyline geoPolyline, double angleDistance, int pointsPerCircle, bool allowParallels)
{
geoPolyline = (GeoPolyline)geoPolyline.Clone();
double minAngle = Math.Sin(Math.Abs(angleDistance)) * Math.Sin(Math.PI / pointsPerCircle);
geoPolyline.ReduceSegments(minAngle);
geoPolyline.Densify(minAngle);
GnomonicProjection projection;
IGeometry geometry;
projectGeography(geoPolyline, out projection, out geometry);
Polyline planePolyline = (Polyline)geometry;
GeographyCollection geographyCollection = new GeographyCollection();
Polygon temp = new Polygon();
List<Polygon> partialBuffers = new List<Polygon>();
ICollection<IGeometry> unionResult = null;
int c = 0;
foreach (GeoPath path in geoPolyline.Paths)
{
for (int i = 0; i < path.Vertices.Count - 1; i++)
{
GeoPoint p = path.Vertices[i];
GeoPolygon tempPolygon = getPointBuffer(p, angleDistance, pointsPerCircle);
geographyCollection.Clear();
geographyCollection.Add(tempPolygon);
GeometryCollection gc = GeometrySpreader.GetGeometries(geographyCollection, projection);
if (gc[0] is Polygon)
unionResult = temp.Union((Polygon)gc[0]);
if (unionResult.Count > 0)
temp = (Polygon)((GeometryCollection)unionResult)[0];
c++;
if (c == 3)
{
partialBuffers.Add(temp);
temp = new Polygon();
c = 0;
}
}
}
if (temp.CoordinateCount > 0)
partialBuffers.Add(temp);
Polygon planeBuffer = mergePartialBuffers(partialBuffers, allowParallels);
GeometryCollection geometryCollection = new GeometryCollection();
geometryCollection.Add(planeBuffer);
geographyCollection = GeometrySpreader.GetGeographies(geometryCollection, projection);
foreach (IGeography g in geographyCollection)
if (g is GeoPolygon)
return (GeoPolygon)g;
return new GeoPolygon();
}
private static void projectGeography(IGeography geography, out GnomonicProjection projection, out IGeometry geometry)
{
GeographyCollection geographyCollection = new GeographyCollection();
geographyCollection.Add(geography);
double centerLatitude, centerLongitude;
GnomonicProjection.GetCenter(geography.ExtractPoints(), out centerLatitude, out centerLongitude);
projection = new GnomonicProjection(centerLongitude, centerLatitude);
GeometryCollection geometryCollection = GeometrySpreader.GetGeometries(geographyCollection, projection);
if (geometryCollection.Count > 0)
geometry = geometryCollection[0];
else
geometry = null;
}
private static Polygon getBoundsBuffer(GeoPolygon polygon, GnomonicProjection projection, double distance, int pointsPerCircle, bool allowParallels)
{
Polygon temp = new Polygon();
List<Polygon> partialBuffers = new List<Polygon>();
GeographyCollection geographyCollection = new GeographyCollection();
ICollection<IGeometry> unionResult = null;
int c = 0;
foreach (GeoContour contour in polygon.Contours)
{
for (int i = 0; i < contour.Vertices.Count; i++)
{
GeoPoint p = contour.Vertices[i];
GeoPolygon tempPolygon = getPointBuffer(p, Math.Abs(distance), pointsPerCircle);
geographyCollection.Clear();
geographyCollection.Add(tempPolygon);
GeometryCollection gc = GeometrySpreader.GetGeometries(geographyCollection, projection);
if(gc[0] is Polygon)
unionResult = temp.Union((Polygon)gc[0]);
if (unionResult.Count > 0)
temp = (Polygon)((GeometryCollection)unionResult)[0];
c++;
if (c == 3)
{
partialBuffers.Add(temp);
temp = new Polygon();
c = 0;
}
}
}
if (temp.CoordinateCount > 0)
partialBuffers.Add(temp);
return mergePartialBuffers(partialBuffers, allowParallels);
}
