Package org.locationtech.jts.operation.distance3d

Class Distance3DOp

java.lang.Object
org.locationtech.jts.operation.distance3d.Distance3DOp
public class Distance3DOp extends Object
Find two points on two 3D Geometrys which lie within a given distance, or else are the nearest points on the geometries (in which case this also provides the distance between the geometries).

3D geometries have vertex Z ordinates defined. 3D Polygons are assumed to lie in a single plane (which is enforced if not actually the case). 3D LineStrings and Points may have any configuration.

The distance computation also finds a pair of points in the input geometries which have the minimum distance between them. If a point lies in the interior of a line segment, the coordinate computed is a close approximation to the exact point.

The algorithms used are straightforward O(n^2) comparisons. This worst-case performance could be improved on by using Voronoi techniques or spatial indexes.

Version:
1.7

  • Field Details

    • geom

      private Geometry[] geom

    • terminateDistance

      private double terminateDistance

    • minDistanceLocation

      private GeometryLocation[] minDistanceLocation

    • minDistance

      private double minDistance

    • isDone

      private boolean isDone

  • Constructor Details

    • Distance3DOp

      public Distance3DOp(Geometry g0, Geometry g1)
      Constructs a DistanceOp that computes the distance and nearest points between the two specified geometries.
      Parameters:
      g0 - a Geometry
      g1 - a Geometry

    • Distance3DOp

      public Distance3DOp(Geometry g0, Geometry g1, double terminateDistance)
      Constructs a DistanceOp that computes the distance and nearest points between the two specified geometries.
      Parameters:
      g0 - a Geometry
      g1 - a Geometry
      terminateDistance - the distance on which to terminate the search

  • Method Details

    • distance

      public static double distance(Geometry g0, Geometry g1)
      Compute the distance between the nearest points of two geometries.
      Parameters:
      g0 - a Geometry
      g1 - another Geometry
      Returns:
      the distance between the geometries

    • isWithinDistance

      public static boolean isWithinDistance(Geometry g0, Geometry g1, double distance)
      Test whether two geometries lie within a given distance of each other.
      Parameters:
      g0 - a Geometry
      g1 - another Geometry
      distance - the distance to test
      Returns:
      true if g0.distance(g1) <= distance

    • nearestPoints

      public static Coordinate[] nearestPoints(Geometry g0, Geometry g1)
      Compute the the nearest points of two geometries. The points are presented in the same order as the input Geometries.
      Parameters:
      g0 - a Geometry
      g1 - another Geometry
      Returns:
      the nearest points in the geometries

    • distance

      public double distance()
      Report the distance between the nearest points on the input geometries.
      Returns:
      the distance between the geometries, or 0 if either input geometry is empty
      Throws:
      IllegalArgumentException - if either input geometry is null

    • nearestPoints

      public Coordinate[] nearestPoints()
      Report the coordinates of the nearest points in the input geometries. The points are presented in the same order as the input Geometries.
      Returns:
      a pair of Coordinates of the nearest points

    • nearestLocations

      public GeometryLocation[] nearestLocations()
      Report the locations of the nearest points in the input geometries. The locations are presented in the same order as the input Geometries.
      Returns:
      a pair of GeometryLocations for the nearest points

    • updateDistance

      private void updateDistance(double dist, GeometryLocation loc0, GeometryLocation loc1, boolean flip)

    • computeMinDistance

      private void computeMinDistance()

    • mostPolygonalIndex

      private int mostPolygonalIndex()
      Finds the index of the "most polygonal" input geometry. This optimizes the computation of the best-fit plane, since it is cached only for the left-hand geometry.
      Returns:
      the index of the most polygonal geometry

    • computeMinDistanceMultiMulti

      private void computeMinDistanceMultiMulti(Geometry g0, Geometry g1, boolean flip)

    • computeMinDistanceOneMulti

      private void computeMinDistanceOneMulti(Geometry g0, Geometry g1, boolean flip)

    • computeMinDistanceOneMulti

      private void computeMinDistanceOneMulti(PlanarPolygon3D poly, Geometry geom, boolean flip)

    • polyPlane

      private static PlanarPolygon3D polyPlane(Geometry poly)
      Convenience method to create a Plane3DPolygon
      Parameters:
      poly -
      Returns:

    • computeMinDistance

      private void computeMinDistance(Geometry g0, Geometry g1, boolean flip)

    • computeMinDistancePolygonPolygon

      private void computeMinDistancePolygonPolygon(PlanarPolygon3D poly0, Polygon poly1, boolean flip)
      Computes distance between two polygons. To compute the distance, compute the distance between the rings of one polygon and the other polygon, and vice-versa. If the polygons intersect, then at least one ring must intersect the other polygon. Note that it is NOT sufficient to test only the shell rings. A counter-example is a "figure-8" polygon A and a simple polygon B at right angles to A, with the ring of B passing through the holes of A. The polygons intersect, but A's shell does not intersect B, and B's shell does not intersect A.
      Parameters:
      poly0 -
      poly1 -
      geomIndex -

    • computeMinDistancePolygonRings

      private void computeMinDistancePolygonRings(PlanarPolygon3D poly, Polygon ringPoly, boolean flip)
      Compute distance between a polygon and the rings of another.
      Parameters:
      poly -
      ringPoly -
      geomIndex -

    • computeMinDistancePolygonLine

      private void computeMinDistancePolygonLine(PlanarPolygon3D poly, LineString line, boolean flip)

    • intersection

      private Coordinate intersection(PlanarPolygon3D poly, LineString line)

    • computeMinDistancePolygonPoint

      private void computeMinDistancePolygonPoint(PlanarPolygon3D polyPlane, Point point, boolean flip)

    • computeMinDistanceLineLine

      private void computeMinDistanceLineLine(LineString line0, LineString line1, boolean flip)

    • computeMinDistanceLinePoint

      private void computeMinDistanceLinePoint(LineString line, Point point, boolean flip)

    • computeMinDistancePointPoint

      private void computeMinDistancePointPoint(Point point0, Point point1, boolean flip)

    • segmentPoint

      private static Coordinate segmentPoint(Coordinate p0, Coordinate p1, double d0, double d1)
      Computes a point at a distance along a segment specified by two relatively proportional values. The fractional distance along the segment is d0/(d0+d1).
      Parameters:
      p0 - start point of the segment
      p1 - end point of the segment
      d0 - proportional distance from start point to computed point
      d1 - proportional distance from computed point to end point
      Returns:
      the computed point