Class CoordinateSequences

  • public class CoordinateSequences
    extends CoordinateSequences
    Utility functions for coordinate sequences (extends the same named JTS class)
    Andrea Aime - OpenGeo, Martin Davis - OpenGeo
    • Constructor Detail

      • CoordinateSequences

        public CoordinateSequences()
    • Method Detail

      • isCCW

        public static boolean isCCW​(CoordinateSequence ring)
        Computes whether a ring defined by an array of Coordinates is oriented counter-clockwise.
        • The list of points is assumed to have the first and last points equal.
        • This will handle coordinate lists which contain repeated points.
        This algorithm is only guaranteed to work with valid rings. If the ring is invalid (e.g. self-crosses or touches), the computed result may not be correct.
        ring - an array of Coordinates forming a ring
        true if the ring is oriented counter-clockwise.
      • computeOrientation

        public static int computeOrientation​(CoordinateSequence cs,
                                             int p1,
                                             int p2,
                                             int q)
      • coordinateDimension

        public static int coordinateDimension​(Geometry g)
        Gets the dimension of the coordinates in a Geometry, by reading it from a component CoordinateSequence. This will be usually either 2 or 3.
        g - a Geometry
        the dimension of the coordinates in the Geometry
      • coordinateDimension

        public static int coordinateDimension​(CoordinateSequence seq)
        Gets the effective dimension of a CoordinateSequence. This is a workaround for the issue that CoordinateArraySequence does not keep an accurate dimension - it always reports dim=3, even if there is no Z ordinate (ie they are NaN). This method checks for that case and reports dim=2. Only the first coordinate is checked.

        There is one small hole: if a CoordinateArraySequence is empty, the dimension will be reported as 3.

        seq - a CoordinateSequence
        the effective dimension of the coordinate sequence
      • equalsND

        public static boolean equalsND​(Geometry g1,
                                       Geometry g2)
        Returns true if the two geometries are equal in N dimensions (normal geometry equality is only 2D)