com.vividsolutions.jts.operation.overlay.snap

Class GeometrySnapper


  • public class GeometrySnapper
extends Object
    Snaps the vertices and segments of a Geometry to another Geometry's vertices. A snap distance tolerance is used to control where snapping is performed. Snapping one geometry to another can improve robustness for overlay operations by eliminating nearly-coincident edges (which cause problems during noding and intersection calculation). Too much snapping can result in invalid topology beging created, so the number and location of snapped vertices is decided using heuristics to determine when it is safe to snap. This can result in some potential snaps being omitted, however.

    • Constructor Detail

      • GeometrySnapper

        public GeometrySnapper(Geometry srcGeom)
        Creates a new snapper acting on the given geometry
        Parameters:
        srcGeom - the geometry to snap

    • Method Detail

      • computeOverlaySnapTolerance

        public static double computeOverlaySnapTolerance(Geometry g)
        Estimates the snap tolerance for a Geometry, taking into account its precision model.
        Parameters:
        g - a Geometry
        Returns:
        the estimated snap tolerance

      • computeSizeBasedSnapTolerance

        public static double computeSizeBasedSnapTolerance(Geometry g)

      • computeOverlaySnapTolerance

        public static double computeOverlaySnapTolerance(Geometry g0,
                                                 Geometry g1)

      • snap

        public static Geometry[] snap(Geometry g0,
                              Geometry g1,
                              double snapTolerance)
        Snaps two geometries together with a given tolerance.
        Parameters:
        g0 - a geometry to snap
        g1 - a geometry to snap
        snapTolerance - the tolerance to use
        Returns:
        the snapped geometries

      • snapToSelf

        public static Geometry snapToSelf(Geometry g0,
                                  double snapTolerance,
                                  boolean cleanResult)

      • snapTo

        public Geometry snapTo(Geometry snapGeom,
                       double snapTolerance)
        Snaps the vertices in the component LineStrings of the source geometry to the vertices of the given snap geometry.
        Parameters:
        snapGeom - a geometry to snap the source to
        Returns:
        a new snapped Geometry

      • snapToSelf

        public Geometry snapToSelf(double snapTolerance,
                           boolean cleanResult)
        Snaps the vertices in the component LineStrings of the source geometry to the vertices of the given snap geometry.
        Parameters:
        snapTolerance - the snapping tolerance
        cleanResult - whether the result should be made valid
        Returns:
        a new snapped Geometry