Package com.luciad.geodesy

Class TLcdSphereUtil

java.lang.Object
com.luciad.geodesy.TLcdSphereUtil
public class TLcdSphereUtil extends Object
TLcdSphereUtil is a utility class that implements spherical trigonometry. All implementations are based on a sphere with a unity radius. All results are in arc degrees.

  • Constructor Details

    • TLcdSphereUtil

      public TLcdSphereUtil()

  • Method Details

    • metersToArcDegrees

      public static double metersToArcDegrees(double aDistance, double aSphereRadius)
      Converts the given distance in meters into a distance in arc degrees, using the given sphere radius.
      Parameters:
      aDistance - the distance in meters
      aSphereRadius - the radius of the underlying sphere
      Returns:
      a distance on the sphere in degrees

    • arcDegreesToMeters

      public static double arcDegreesToMeters(double aArcDegreeDistance, double aSphereRadius)
      Converts the given distance of the given arc into a distance in meters, using the given sphere radius.
      Parameters:
      aArcDegreeDistance - a distance on the sphere in degrees
      aSphereRadius - the radius of the underlying sphere
      Returns:
      the distance in meters

    • greatCircleDistance

      public static double greatCircleDistance(ILcdPoint aP1, ILcdPoint aP2)
      Calculates the shortest distance between aP1 and aP2. As a result, the difference will never exceed 180 degrees !
      Parameters:
      aP1 - first point.
      aP2 - second point.
      Returns:
      The distance between the two points (in degrees).

    • greatCircleDistance

      public static double greatCircleDistance(double aLon1, double aLat1, double aLon2, double aLat2)
      Great circle distance from aP1 to aP2 in arc degrees !
      Parameters:
      aLon1 - longitude of the first point in degrees.
      aLat1 - latitude of the first point in degrees.
      aLon2 - longitude of the second point in degrees.
      aLat2 - latitude of the second point in degrees.
      Returns:
      The distance between the two points (in degrees).

    • greatCircleDistance

      public static double greatCircleDistance(double aLon1, double aLat1, double aCosLat1, double aLon2, double aLat2, double aCosLat2)
      Great circle distance from aP1 to aP2 in arc degrees !
      Parameters:
      aLon1 - longitude of start point of line segment in degrees.
      aLat1 - latitude of start point of line segment in degrees.
      aCosLat1 - cosine of the latitude of the start point.
      aLon2 - longitude of end point of line segment in degrees.
      aLat2 - latitude of end point of line segment in degrees.
      aCosLat2 - cosine of the latitude of the end point.
      Returns:
      the distance in degrees.

    • distanceToGeodesic

      public static double distanceToGeodesic(ILcdPoint aP1, ILcdPoint aP2, ILcdPoint aP3, double aAngle)
      Calculates the distance between the geodesic line determined by aP1-aP2 and the point aP3, at a certain angle aAngle. Returns result in degrees.
      Parameters:
      aP1 - defining point of geodesic line.
      aP2 - defining point of geodesic line.
      aP3 - point from which the distance needs to be calculated.
      aAngle - defines the angle between the geodesic lines defined by the point aP3 and the point of crossing and the geodesic line defined by aP1 and aP2 and the point of crossing. Should be specified in degrees.
      Returns:
      the distance in degrees.

    • distanceToGeodesic

      public static double distanceToGeodesic(double aLon1, double aLat1, double aLon2, double aLat2, double aLon3, double aLat3, double aAngle)
      Calculates the distance between the geodesic line through (aLon1,aLat1)-(aLon2,aLat2) and point (aLon3,aLat3), at a certain angle aAngle. Returns result in degrees.
      Parameters:
      aLon1 - longitude of defining point of geodesic line in degrees.
      aLat1 - latitude of defining point of geodesic line in degrees.
      aLon2 - longitude of defining point of geodesic line in degrees.
      aLat2 - latitude of defining point of geodesic line in degrees.
      aLon3 - longitude of third point in degrees.
      aLat3 - latitude of third point in degrees.
      aAngle - defines the angle between the geodesic defined by (aLon3,aLat3) and the point of crossing and the geodesic defined by (aLon2,aLat2) and the point of crossing.
      Returns:
      the distance in degrees.

    • closestDistanceToGeodesic

      public static double closestDistanceToGeodesic(ILcdPoint aP1, ILcdPoint aP2, ILcdPoint aP3, boolean aClipToLineSegment)
      Calculates the shortest distance between the geodetic line (segment) aP1-aP2 and point aP3.
      Parameters:
      aP1 - start point of the geodesic.
      aP2 - end point of the geodesic.
      aP3 - point from which the distance has to be calculated.
      aClipToLineSegment - if false, the shortest distance will be calculated for the whole geodesic. Otherwise it will only be calculated for the geodesic line segment aP1-aP2.
      Returns:
      the distance in degrees.

    • closestPointOnShape

      public static double closestPointOnShape(ILcdPoint aPoint, ILcdShape aShape, ILcd2DEditablePoint aResultSFCT)
      Finds the shortest distance from the given point to the given shape. The corresponding point on the shape is returned in the side effect parameter.

      This methods supports geodetic and rhumb ILcdPolyline and ILcdPolygon instances.

      Parameters:
      aPoint - the starting point
      aShape - the shape for which to find the point closest to aPoint
      aResultSFCT - side-effect parameter for the resulting point
      Returns:
      the shortest distance in degrees
      Throws:
      IllegalArgumentException - if the provided shape is not supported

    • closestPointOnGeodesic

      public static double closestPointOnGeodesic(ILcdPoint aP1, ILcdPoint aP2, ILcdPoint aP3, ILcd2DEditablePoint aPSFCT)
      Calculates the shortest distance between the geodesic line segment aP1-aP2 and point aP3, and also the point on the geodesic aP1-aP2 that is the closest to point aP3.
      Parameters:
      aP1 - start point of geodesic.
      aP2 - end point of geodesic.
      aP3 - point from which the distance has to be calculated.
      aPSFCT - point that will contain the coordinate of the point on the geodesic line segment aP1-aP2 that is calculated to be at the shortest distance to aP3.
      Returns:
      the distance in degrees.

    • closestPointOnGeodesic

      public static double closestPointOnGeodesic(ILcdPoint aP1, ILcdPoint aP2, ILcdPoint aP3, boolean aClipToLineSegment, ILcd2DEditablePoint aPSFCT)
      Calculates the shortest distance between the geodesic through aP1-aP2 and the point aP3, and also the point on the geodesic aP1-aP2 that is the closest to point aP3. The flag aClipToLineSegment determines whether the geodesic is to be considered as the geodesic line segment defined by the two points or as the geodesic line through the two points.
      Parameters:
      aP1 - start point of geodesic.
      aP2 - end point of geodesic.
      aP3 - point from which the distance has to be calculated.
      aClipToLineSegment - Description of Parameter
      aPSFCT - point that will contain the coordinate of the point on the geodesic through aP1-aP2 that is calculated to be at the shortest distance to aP3. This point may be clipped onto the line segment depending on the value of aClipToLineSegment.
      Returns:
      the distance in degrees.

    • geodesicArea

      public static double geodesicArea(ILcdPoint[] aPts, int aN)
      Geodesic surface area of a polygon on the sphere.

      Constraints: (aN > 2) and (aPts.length >= aN).

      Parameters:
      aPts - array of ILcdPoint objects.
      aN - aPts[0..aN-1] defines the polygon on the sphere.
      Returns:
      the surface area in radians2. Positive for counterclockwise polygons, negative otherwise.

    • geodesicArea

      public static double geodesicArea(ILcdPoint[] aPts, int aN, double aRadius)
      Geodesic surface area of a polygon on the sphere.

      Constraints: (aN > 2) and (aPts.length >= aN).

      Parameters:
      aPts - array of ILcdPoint objects.
      aN - aPts[0..aN-1] defines the polygon on the sphere.
      aRadius - radius of the sphere.
      Returns:
      the surface area in meter2. Positive for counterclockwise polygons, negative otherwise.
      Since:
      2022.0

    • geodesicArea

      public static double geodesicArea(ILcdShape aShape, double aRadius)
      Calculates the geodesic area of a shape.

      Following shapes are supported:

      • ILcdPolygon that doesn't self-intersect
      • ILcdComplexPolygon that is geometrically valid: no individual polygon can be self-intersecting, and no two polygons may intersect. Nested polygons are allowed.
      • ILcdSurface with external and internal rings as polygons. The surface must also be geometrically valid.
      • ILcdShapeList containing supported shapes.

      This method does not fully check the validity of the arguments, since it is computationally too expensive to do so. Passing an unsupported shape may result in an IllegalArgumentException being thrown, or may result in an undefined return value.

      Parameters:
      aShape - a shape adhering to the requirements above
      aRadius - radius of the sphere, in meter
      Returns:
      the surface area in meter2, always positive
      Since:
      2022.0
      See Also:

    • orientation2D

      public static int orientation2D(ILcdPoint[] aPoints, int aNumberOfPoints)
      Calculates the orientation of an array of points on a sphere.

      Constraints: (aNumberOfPoints > 2) and (aPoints.length >= aNumberOfPoints).

      Parameters:
      aPoints - array of ILcdPoint objects (first point is not repeated).
      aNumberOfPoints - the number of points of the array to take into account.
      Returns:
      the orientation of the polygon. Possible return values are ILcdPolygon#CLOCKWISE and ILcdPolygon#COUNTERCLOCKWISE.

    • orientation2D

      public static int orientation2D(ILcdPointList aPointList)
      Calculates the orientation of a point list on a sphere.

      Constraints: (aPointList.length > 2).

      Parameters:
      aPointList - the point list to compute the orientation of. Note that this implies interpreting the point list as a polygon. The last point of the point list does not need to be equal to the first point.
      Returns:
      the orientation of the polygon which would be described by the point list. Possible return values are ILcdPolygon.CLOCKWISE and ILcdPolygon.COUNTERCLOCKWISE.

    • forwardAzimuth2D

      public static double forwardAzimuth2D(ILcdPoint aP1, ILcdPoint aP2)
      Forward azimuth from aP1 to aP2 in RADIANS! The resulting value lies between [0.0, 2.0*Math.PI]. See Maling p. 62.
      Parameters:
      aP1 - start point.
      aP2 - end point.
      Returns:
      result in radians.

    • greatCirclePointSFCT

      public static void greatCirclePointSFCT(ILcdPoint aP1, double aDistance, double aAzimuth, ILcd2DEditablePoint aGreatCirclePoint)
      Calculates aGreatCirclePoint to be a point on the great circle through aP1, located at a distance aD and forward azimuth aAzimuth.
      Parameters:
      aP1 - start ILcdPoint on the sphere.
      aDistance - distance expressed in arc degrees.
      aAzimuth - azimuth expressed in degrees.
      aGreatCirclePoint - ILcd2DEditablePoint on the sphere as side effect.

    • greatCirclePointSFCT

      public static void greatCirclePointSFCT(ILcdPoint aP1, ILcdPoint aP2, double aK, ILcd2DEditablePoint aGreatCirclePoint)
      Calculates aGreatCirclePoint to be a point on the great circle through aP1 and aP2, located at a fraction aK of the shortest distance between the two point aP1 and aP2.
      Parameters:
      aP1 - start point of line segment.
      aP2 - end point of line segment.
      aK - fraction of distance between aP1-aP2 to take.
      aGreatCirclePoint - point at fraction aK as side effect.

    • geoc2llhSFCT

      public static void geoc2llhSFCT(ILcdPoint aXYZPoint, double aRadius, ILcd3DEditablePoint aLLHOut)
      Coordinate conversion from earth centered, earth fixed cartesian coordinates (X,Y,Z) to geodetic coordinate (l, j ,h ), with h the height above the sphere.
      Parameters:
      aXYZPoint - earth centered earth fixed cartesian coordinates (meters).
      aRadius - radius of the sphere (meters).
      aLLHOut - geodetic coordinate w.r.t. sphere, height expressed in meters.

    • llh2geocSFCT

      public static void llh2geocSFCT(ILcdPoint aLLHPoint, double aRadius, ILcd3DEditablePoint aXYZOut)
      Coordinate conversion from geodetic coordinate (l, j ,h ) to earth centered, earth fixed Cartesian coordinates (X,Y,Z) .
      Parameters:
      aLLHPoint - Geodetic coordinate (l, j ,h ).
      aRadius - radius of the sphere.
      aXYZOut - earth centered earth fixed cartesian coordinate.

    • greatCircleDistanceWest2East

      public static double greatCircleDistanceWest2East(ILcdPoint aP1, ILcdPoint aP2)
      Calculates the distance between aP1 and aP2, tracing the sphere from west to east.
      Parameters:
      aP1 - start point of line segment.
      aP2 - end point of line segment.
      Returns:
      distance in arc degrees.

    • greatCircleDistanceWest2East

      public static double greatCircleDistanceWest2East(double aLon1, double aLat1, double aLon2, double aLat2)
      Calculates the distance between aP1 and aP2, tracing the sphere from west to east.
      Parameters:
      aLon1 - longitude of the start point of the line segment (in degrees).
      aLat1 - latitude of the start point of the line segment (in degrees).
      aLon2 - longitude of the end point of the line segment (in degrees).
      aLat2 - latitude of the end point of the line segment (in degrees).
      Returns:
      distance in arc degrees.

    • greatCircleDistanceEast2West

      public static double greatCircleDistanceEast2West(ILcdPoint aP1, ILcdPoint aP2)
      Calculates the distance between aP1 and aP2, tracing the sphere from east to west.
      Parameters:
      aP1 - start point of line segment.
      aP2 - end point of line segment.
      Returns:
      distance in arc degrees.

    • greatCircleDistanceEast2West

      public static double greatCircleDistanceEast2West(double aLon1, double aLat1, double aLon2, double aLat2)
      Calculates the distance between aP1 and aP2, tracing the sphere from east to west.
      Parameters:
      aLon1 - longitude of the start point of the line segment (in degrees).
      aLat1 - latitude of the start point of the line segment (in degrees).
      aLon2 - longitude of the end point of the line segment (in degrees).
      aLat2 - latitude of the end point of the line segment (in degrees).
      Returns:
      distance in arc degrees.

    • intersection2DLineSegments

      public static int intersection2DLineSegments(ILcdPoint aP1, ILcdPoint aP2, ILcdPoint aP3, ILcdPoint aP4, ILcd2DEditablePoint aLLResultSFCT1, ILcd2DEditablePoint aLLResultSFCT2)
      Intersection of two geodesic line segments on a sphere. The intersection point should lie on both line segments.
      Parameters:
      aP1 - start point of first line segment.
      aP2 - start point of first line segment.
      aP3 - end point of second line segment.
      aP4 - end point of second line segment.
      aLLResultSFCT1 - side effect parameter that will contain the intersection point if there is any.
      aLLResultSFCT2 - side effect parameter that will contain the intersection point if there is any.
      Returns:
      the number of intersection points. Possible return codes are 0 if there is no intersection point, 1 if there is one intersection point, and -1 if the line segments overlap each other. In the latter case the two side effect parameters contain the start and end point of the overlapping interval.

    • intersects2DLS

      public static boolean intersects2DLS(ILcdPoint aP1, ILcdPoint aP2, ILcdPoint aP3, ILcdPoint aP4)
      Checks whether two geodesic line segments defined by the pairs aP1-aP2 and aP3-aP4 intersect each other.
      Parameters:
      aP1 - start point of first line segment.
      aP2 - end point of first line segment.
      aP3 - start point of second line segment.
      aP4 - end point of second line segment.
      Returns:
      true if the two line segments have an intersection point, false otherwise.
      See Also:

    • intersects2DLS

      public static boolean intersects2DLS(double aLon1, double aLat1, double aLon2, double aLat2, double aLon3, double aLat3, double aLon4, double aLat4)
      Checks whether two geodesic line segments defined by the pairs (aLon1,aLat1)-(aLon2,aLat2) and (aLon3,aLat3)-(aLon4,aLat4) intersect each other.
      Parameters:
      aLon1 - longitude of start point of first line segment (in degrees).
      aLat1 - latitude of end point of first line segment (in degrees).
      aLon2 - longitude of start point of first line segment (in degrees).
      aLat2 - latitude of end point of first line segment (in degrees).
      aLon3 - longitude of start point of second line segment (in degrees).
      aLat3 - latitude of end point of second line segment (in degrees).
      aLon4 - longitude of start point of second line segment (in degrees).
      aLat4 - latitude of end point of second line segment (in degrees).
      Returns:
      true if the two line segments have an intersection point, false otherwise.

    • intersects2DLineSegments

      public static boolean intersects2DLineSegments(ILcdPoint aP1, ILcdPoint aP2, ILcdPoint aP3, ILcdPoint aP4)
      Checks whether two geodesic line segments defined by the pairs aP1-aP2 and aP3-aP4 intersect each other.
      Parameters:
      aP1 - start point of first line segment.
      aP2 - start point of first line segment.
      aP3 - end point of second line segment.
      aP4 - end point of second line segment.
      Returns:
      true if the two line segments have an intersection point that lies on both line segments, false otherwise.
      See Also:

    • intersects2DLineSegments

      public static boolean intersects2DLineSegments(double aLon1, double aLat1, double aLon2, double aLat2, double aLon3, double aLat3, double aLon4, double aLat4)
      Checks whether two geodesic line segments defined by the pairs (aLon1,aLat1)-(aLon2,aLat2) and (aLon3,aLat3)-(aLon4,aLat4) intersect each other.
      Parameters:
      aLon1 - longitude of start point of first line segment (in degrees).
      aLat1 - latitude of end point of first line segment (in degrees).
      aLon2 - longitude of start point of first line segment (in degrees).
      aLat2 - latitude of end point of first line segment (in degrees).
      aLon3 - longitude of start point of second line segment (in degrees).
      aLat3 - latitude of end point of second line segment (in degrees).
      aLon4 - longitude of start point of second line segment (in degrees).
      aLat4 - latitude of end point of second line segment (in degrees).
      Returns:
      true if the two line segments have an intersection point that lies on both line segments, false otherwise.
      See Also:

    • intersection2DLSSFCT

      @Deprecated public static void intersection2DLSSFCT(ILcdPoint aP1, ILcdPoint aP2, ILcdPoint aP3, ILcdPoint aP4, ILcd2DEditablePoint aLLResultSFCT) throws IllegalArgumentException
      Deprecated.
      the name of this method contradicts the actual behavior, use intersectionGeodesicGeodesic(com.luciad.shape.ILcdPoint, com.luciad.shape.ILcdPoint, com.luciad.shape.ILcdPoint, com.luciad.shape.ILcdPoint, com.luciad.shape.shape2D.ILcd2DEditablePoint)
      Calculates the intersection point of two great circle lines (geodesics) defined by the given points. See intersection2DLineSegments(com.luciad.shape.ILcdPoint, com.luciad.shape.ILcdPoint, com.luciad.shape.ILcdPoint, com.luciad.shape.ILcdPoint, com.luciad.shape.shape2D.ILcd2DEditablePoint, com.luciad.shape.shape2D.ILcd2DEditablePoint) for calculating the intersection of line segments.

      Since great circle planes that do no coincide always have two intersection points, the most appropriate is chosen. If one of the two possibilities is on one of the line segments that one is chosen. Otherwise, the one closest to one of the end points is chosen.

      Parameters:
      aP1 - a point on the first geodesic.
      aP2 - another point on the first geodesic. Should not coincide with aP1.
      aP3 - a point on the second geodesic.
      aP4 - another point on the second geodesic. Should not coincide with aP3.
      aLLResultSFCT - the intersection point as side effect.
      Throws:
      IllegalArgumentException - if no intersection point can be found or chosen.

    • intersectionGeodesicGeodesic

      public static void intersectionGeodesicGeodesic(ILcdPoint aP1, ILcdPoint aP2, ILcdPoint aP3, ILcdPoint aP4, ILcd2DEditablePoint aLLResultSFCT) throws IllegalArgumentException
      Calculates the intersection point of two great circle lines (geodesics) defined by the given points. See intersection2DLineSegments(com.luciad.shape.ILcdPoint, com.luciad.shape.ILcdPoint, com.luciad.shape.ILcdPoint, com.luciad.shape.ILcdPoint, com.luciad.shape.shape2D.ILcd2DEditablePoint, com.luciad.shape.shape2D.ILcd2DEditablePoint) for calculating the intersection of line segments.

      Since great circle planes that do no coincide always have two intersection points, the most appropriate is chosen. If one of the two possibilities is on one of the line segments that one is chosen. Otherwise, the one closest to one of the end points is chosen.

      Parameters:
      aP1 - a point on the first geodesic.
      aP2 - another point on the first geodesic. Should not coincide with aP1.
      aP3 - a point on the second geodesic.
      aP4 - another point on the second geodesic. Should not coincide with aP3.
      aLLResultSFCT - the intersection point as side effect.
      Throws:
      IllegalArgumentException - if no intersection point can be found or chosen.
      Since:
      2021.0

    • intersection2DLSSFCT

      @Deprecated public static void intersection2DLSSFCT(double aLon1, double aLat1, double aLon2, double aLat2, double aLon3, double aLat3, double aLon4, double aLat4, ILcd2DEditablePoint aLLP) throws IllegalArgumentException
      Deprecated.
      the name of this method contradicts the actual behavior, use intersectionGeodesicGeodesic(com.luciad.shape.ILcdPoint, com.luciad.shape.ILcdPoint, com.luciad.shape.ILcdPoint, com.luciad.shape.ILcdPoint, com.luciad.shape.shape2D.ILcd2DEditablePoint)
      Calculates the intersection point of two great circle lines defined by the pairs (aLon1,aLat1)-(aLon2,aLat2) and (aLon3,aLat3)-(aLon4,aLat4). The intersection does not necessarily lie on one of the two line segments. Since great circle planes that do no coincide always have two intersection points, the most appropriate is chosen. If one of the two possibilities is on one of the line segments that one is chosen. Otherwise, the one closest to one of the end points is chosen.
      Parameters:
      aLon1 - longitude of start point of first line segment (in degrees).
      aLat1 - latitude of end point of first line segment (in degrees).
      aLon2 - longitude of start point of first line segment (in degrees).
      aLat2 - latitude of end point of first line segment (in degrees).
      aLon3 - longitude of start point of second line segment (in degrees).
      aLat3 - latitude of end point of second line segment (in degrees).
      aLon4 - longitude of start point of second line segment (in degrees).
      aLat4 - latitude of end point of second line segment (in degrees).
      aLLP - the intersection point as side effect.
      Throws:
      IllegalArgumentException - if no intersection point can be found or chosen.

    • intersection2DLSSFCT

      @Deprecated public static int intersection2DLSSFCT(ILcdPoint aP1, ILcdPoint aP2, ILcdPoint aP3, ILcdPoint aP4, ILcd2DEditablePoint aLLResultSFCT1, ILcd2DEditablePoint aLLResultSFCT2)
      Deprecated.
      the name of this method contradicts the actual behavior, use intersectionGeodesicGeodesic(com.luciad.shape.ILcdPoint, com.luciad.shape.ILcdPoint, com.luciad.shape.ILcdPoint, com.luciad.shape.ILcdPoint, com.luciad.shape.shape2D.ILcd2DEditablePoint)
      Calculates the intersection point of two great circle lines defined by the pairs through aP1-aP2 and aP3-aP4 that intersect each other. The points aP1 and aP2 should not coincide nor should the points aP3 and aP4. The intersection does not necessarily lie on one of the two line segments. However, great circle planes that do no coincide always have two intersection points.
      Parameters:
      aP1 - start point of the first line segment.
      aP2 - end point of the first line segment.
      aP3 - start point of the second line segment.
      aP4 - end point of the second line segment.
      aLLResultSFCT1 - the intersection point as side effect.
      aLLResultSFCT2 - the intersection point as side effect.
      Returns:
      the number of intersection points. If the great circle planes do not coincide this will be 2. If they do coincide the return code will be -1.

    • intersects2DSR

      public static boolean intersects2DSR(double aLon1, double aLat1, double aWidth1, double aHeight1, double aLon2, double aLat2, double aWidth2, double aHeight2)
      Checks whether two 2D rectangles intersect.
      Parameters:
      aLon1 - longitude of lower left corner point of the first rectangle in degrees.
      aLat1 - latitude of lower left corner point of the first rectangle in degrees.
      aWidth1 - width of the first rectangle (>=0) in degrees.
      aHeight1 - height of the first rectangle (>=0) in degrees.
      aLon2 - longitude of lower left corner point of the second rectangle in degrees.
      aLat2 - latitude of lower left corner point of the second rectangle in degrees.
      aWidth2 - width of the second rectangle (>=0) in degrees.
      aHeight2 - height of the second rectangle (>=0) in degrees.
      Returns:
      true if the two rectangles intersect each other, false otherwise.

    • overlaps2DSR

      public static boolean overlaps2DSR(double aLon1, double aLat1, double aWidth1, double aHeight1, double aLon2, double aLat2, double aWidth2, double aHeight2)
      Checks whether two 2D rectangles overlap.
      Parameters:
      aLon1 - longitude of lower left corner point in degrees.
      aLat1 - latitude of lower left corner point in degrees.
      aWidth1 - width of the rectangle (>=0) in degrees.
      aHeight1 - height of the rectangle (>=0) in degrees.
      aLon2 - longitude of lower left corner point in degrees.
      aLat2 - latitude of lower left corner point in degrees.
      aWidth2 - width of the rectangle (>=0) in degrees.
      aHeight2 - height of the rectangle (>=0) in degrees.
      Returns:
      true if the two rectangles overlap each other, false otherwise.

    • overlaps2DSRLowLeft

      public static boolean overlaps2DSRLowLeft(double aLon1, double aLat1, double aWidth1, double aHeight1, double aLon2, double aLat2, double aWidth2, double aHeight2)
      Checks whether two 2D rectangles overlap. It includes the lower and left border for overlap, but excludes the upper and right border.
      Parameters:
      aLon1 - longitude of lower left corner point in degrees.
      aLat1 - latitude of lower left corner point in degrees.
      aWidth1 - width of the rectangle (>=0) in degrees.
      aHeight1 - height of the rectangle (>=0) in degrees.
      aLon2 - longitude of lower left corner point in degrees.
      aLat2 - latitude of lower left corner point in degrees.
      aWidth2 - width of the rectangle (>=0) in degrees.
      aHeight2 - height of the rectangle (>=0) in degrees.
      Returns:
      true if the two rectangles overlap each other, false otherwise.

    • contains2D

      public static boolean contains2D(ILcdPoint aP1, ILcdPoint aP2, ILcdPoint aPoint)
      Checks whether the point aPoint lies on the geodesic line segment aP1-aP2.
      Parameters:
      aP1 - start point of line segment.
      aP2 - end point of line segment.
      aPoint - point to be checked.
      Returns:
      true if the point lies on the line segment, false otherwise.

    • circleContains2D

      public static boolean circleContains2D(ILcdPoint aCenter, double aCircleRadius, double aSphereRadius, ILcdPoint aPoint)
      Checks whether the point aPoint lies within the circle (aCenter,aCircleRadius) on the sphere with radius aSphereRadius.
      Parameters:
      aCenter - center point of the circle.
      aCircleRadius - radius of the circle in meters.
      aSphereRadius - radius of the sphere in meters.
      aPoint - point to be tested.
      Returns:
      true if the point lies inside the circle, false otherwise.

    • arcContains2D

      public static boolean arcContains2D(ILcdPoint aCenter, double aMajorAxe, double aMinorAxe, double aRotAngle, double aStartAngle, double aArcAngle, double aSphereRadius, ILcdPoint aLLPoint)
      Checks whether the point aLLPoint lies on the elliptical arc segment.
      Parameters:
      aCenter - center point of the elliptical arc.
      aMajorAxe - major axis of the elliptical arc (meters).
      aMinorAxe - minor axis of the elliptical arc (meters).
      aRotAngle - rotation angle of the axis in degrees.
      aStartAngle - start angle of the arc segment in degrees, positive counter clockwise, starting from 3O'clock.
      aArcAngle - length of arc segment in arc degrees.
      aSphereRadius - radius of the sphere in meters.
      aLLPoint - point to be tested.
      Returns:
      true if the point lies on the elliptical arc segment, false otherwise.

    • arcContains2D

      public static boolean arcContains2D(ILcdArc aArc, double aSphereRadius, ILcdPoint aLLPoint)
      Checks whether the point aLLPoint lies on the elliptical arc segment.
      Parameters:
      aArc - elliptical arc.
      aSphereRadius - radius of the sphere in meters.
      aLLPoint - point to be tested.
      Returns:
      true if the point lies on the elliptical arc segment, false otherwise.

    • polygonContains2D

      public static boolean polygonContains2D(ILcdPolygon aPolygon, ILcdPoint aPoint)
      Checks if a point lies inside a polygon. We define the ILcdPoint aPoint to be inside if:
      • aPoint interacts with the polygon bounds
      • aPoint has an odd number of polygon edge intersections within a distance of 180 degrees in northern direction (azimuth zero degrees) if this fails we also try in southern direction
      The polygon thus shouldn't be larger than a hemisphere.
      Parameters:
      aPolygon - polygon w.r.t. which the test is performed.
      aPoint - the point to be tested.
      Returns:
      true if the point lies inside the polygon, false otherwise.

    • polygonContains2D

      public static boolean polygonContains2D(ILcdPolygon aPolygon, double aLonP, double aLatP)
      Checks if a point lies inside a polygon. We define the point with coordinates aLonP,aLatP to be inside if:
      • the point interacts with the polygon bounds
      • the point has an odd number of polygon edge intersections within a distance of 180 degrees in northern direction (azimuth zero degrees) if this fails we also try in southern direction
      The polygon thus shouldn't be larger than a hemisphere.
      Parameters:
      aPolygon - polygon w.r.t. which the test is performed.
      aLonP - longitude of the point to be tested in degrees.
      aLatP - latitude of the point to be tested in degrees.
      Returns:
      true if the point lies inside the polygon, false otherwise.

    • calculateBounds

      public static void calculateBounds(ILcdPointList aPointList, boolean aPolygon, ILcd2DEditableBounds aBoundsSFCT) throws TLcdNoBoundsException
      Calculates the bounding box containing the polyline/polygon formed by the point list assuming great circle line segments.
      Parameters:
      aPointList - polygon or polyline.
      aPolygon - if true the point list is treated as a polygon, otherwise as a polyline.
      aBoundsSFCT - the bounding box for the polyline/polygon as side effect.
      Throws:
      TLcdNoBoundsException - if the polyline/polygon doesn't have a bounding box.

    • contains2DLS

      public static boolean contains2DLS(ILcdPoint aP1, ILcdPoint aP2, ILcdPoint aP3, ILcdPoint aP4)
      Checks if the line segment aP1-aP2 contains the line segment aP3-aP4.
      Parameters:
      aP1 - start point of the first line segment.
      aP2 - end point of the first line segment.
      aP3 - start point of the second line segment.
      aP4 - end point of the second line segment.
      Returns:
      true if both end points of the second line segment lie on the first line segment, false otherwise.

    • contains2DSR

      public static boolean contains2DSR(double aLon1, double aLat1, double aWidth1, double aHeight1, double aLon2, double aLat2, double aWidth2, double aHeight2)
      Checks whether a 2D rectangle contains another rectangle.
      Parameters:
      aLon1 - longitude of lower left corner point in degrees.
      aLat1 - latitude of lower left corner point in degrees.
      aWidth1 - width of the rectangle (>=0) in degrees.
      aHeight1 - height of the rectangle (>=0) in degrees.
      aLon2 - longitude of lower left corner point in degrees.
      aLat2 - latitude of lower left corner point in degrees.
      aWidth2 - width of the rectangle (>=0) in degrees.
      aHeight2 - height of the rectangle (>=0) in degrees.
      Returns:
      true if the second rectangle lies within the first, false otherwise.

    • intersects2DCircleLineSegment

      public static boolean intersects2DCircleLineSegment(ILcdPoint aCenter, double aRadius, ILcdPoint aP1, ILcdPoint aP2)
      Checks whether a circle and a line segment intersect each other.
      Parameters:
      aCenter - lon-lat coordinate of center point.
      aRadius - radius of circle expressed in arc degrees.
      aP1 - end point of line segment.
      aP2 - end point of line segment.
      Returns:
      true if the circle and the line segment intersect, false otherwise.

    • intersects2DLineSegmentCircularArc

      public static boolean intersects2DLineSegmentCircularArc(ILcdPoint aP1, ILcdPoint aP2, ILcdPoint aCenter, double aRadius, double aStartAngle, double aArcAngle)
      Checks whether a line segment and a circular arc segment intersect each other. The radius of the circular arc has to be provided in degrees.
      Parameters:
      aP1 - end point of the line segment.
      aP2 - end point of the line segment.
      aCenter - center of the circular arc segment.
      aRadius - radius of the circular arc segment in degrees.
      aStartAngle - start angle of arc segment expressed in degrees, positive counter clock wise starting from 3O'Clock.
      aArcAngle - length of arc angle in degrees.
      Returns:
      true if the line segment and the circular arc segment intersect, false otherwise.

    • intersects2DCircularArcCircularArc

      public static boolean intersects2DCircularArcCircularArc(ILcdPoint aCenter1, double aRadius1, double aStartAngle1, double aArcAngle1, ILcdPoint aCenter2, double aRadius2, double aStartAngle2, double aArcAngle2)
      Checks whether two circular arcs intersect each other. The radii of the arcs have to be given in arc degrees!
      Parameters:
      aCenter1 - center point of first circular arc.
      aRadius1 - radius of first circular arc in degrees.
      aStartAngle1 - start angle of arc segment expressed in degrees, positive counter clock wise starting from 3 O'Clock.
      aArcAngle1 - length of arc in degrees.
      aCenter2 - center point of second circular arc.
      aRadius2 - radius of second circular arc in degrees.
      aStartAngle2 - start angle of arc segment expressed in degrees, positive counter clock wise starting from 3 O'Clock.
      aArcAngle2 - length of arc in degrees.
      Returns:
      true if the circular arc segments intersect, false otherwise.

    • bufferContour2DOfSegmentSFCT

      public static void bufferContour2DOfSegmentSFCT(ILcdPoint aStartPoint, ILcdPoint aEndPoint, double aWidth, ILcd2DEditablePoint[] a2DEditablePointArraySFCT)
      Calculates the contour of the rectangle defined by aStartPoint, aEndPoint, and aWidth, as an array of 4 ILcd2DEditablePoint objects. The ordering of the points of the contour is clockwise starting from the first point of the rectangle.

      Because there are only 4 points used to define the contour, the contour representation becomes less accurate when the start and end point are further removed from each other: the connected contour lines no longer lie at the given distance from the axis at each intermediate point. For a more accurate calculation of a buffer contour that uses additional contour points if necessary, please refer to TLcdEllipsoidUtil#computeBufferContour2D.

      Parameters:
      aStartPoint - start point of buffer segment.
      aEndPoint - end point of buffer segment.
      aWidth - distance from the line segment to the contour in arc degrees.
      a2DEditablePointArraySFCT - an initialized array of 4 ILcd2DEditablePoint objects, which will represent the contour polygon.

    • contour2DOfBoundsSFCT

      public static void contour2DOfBoundsSFCT(ILcdBounds aBounds, ILcd2DEditablePoint[] a2DEditablePointArraySFCT)
      Calculates the contour of the given ILcdBounds, as an array of ILcd2DEditablePoint objects.
      Parameters:
      aBounds - bounds object.
      a2DEditablePointArraySFCT - an initialized array of 4 ILcd2DEditablePoint which will contain the contour.

    • bufferContour2DOf2DPolyline

      public static void bufferContour2DOf2DPolyline(ILcdPointList aPointList, double aWidth, ILcd2DEditablePoint[] a2DEditablePointArraySFCT)
      Calculates the contour of the buffer/corridor along a given ILcdPointList at a given width. No two successive points should coincide! The ordering of the points of the contour is clockwise starting from the first point of the rectangle.

      This implementation has the following limitations:

      • contours with holes (i.e., caused by axis intersections) cannot be represented, since the contour is modeled as an ILcd2DEditablePoint array,
      • the corners of the contour at the axis points are sharp instead of rounded, which make it less suitable for buffers that have sharp angles between its consecutive axis segments; it has also has as consequence that the distance between the contour and the axis exceeds the given buffer distance in the corners,
      • the calculated contour is only an estimate, because it uses a reduced number of contour points; when the start and end point of a segment are further removed from each other, the connected contour lines no longer lie at the given distance from the axis at each intermediate point.
      For an improved calculation of a buffer contour that overcomes these limitations, please refer to TLcdEllipsoidUtil#computeBufferContour2D.

      Parameters:
      aPointList - the axis of the buffer.
      aWidth - distance from the axis to the contour in arc degrees.
      a2DEditablePointArraySFCT - an initialized array of aPointList.getPointCount() * 2 ILcd2DEditablePoint objects, which will represent the contour polygon.

    • greatCircleDistance3D

      public static double greatCircleDistance3D(ILcdPoint aPoint1, ILcdPoint aPoint2, double aRadius)
      Calculates the distance to go from point p1 to point p2. Unlike TLcdSphereUtil#greatCircleDistance, which ignores the height of the points, the distance calculations of this method take the heights of the given points into account.
      Parameters:
      aPoint1 - the start (geodetic) point
      aPoint2 - the end (geodetic) point
      aRadius - the radius of the sphere on which to perform the distance calculation
      Returns:
      the 3D distance of the line segment formed by aPoint1 and aPoint2
      Since:
      2022.1