Class AbstractPreparedPolygonContains

  • Direct Known Subclasses:
    PreparedPolygonContains, PreparedPolygonCovers

    abstract class AbstractPreparedPolygonContains
    extends PreparedPolygonPredicate
    A base class containing the logic for computes the contains and covers spatial relationship predicates for a PreparedPolygon relative to all other Geometry classes. Uses short-circuit tests and indexing to improve performance.

    Contains and covers are very similar, and differ only in how certain cases along the boundary are handled. These cases require full topological evaluation to handle, so all the code in this class is common to both predicates.

    It is not possible to short-circuit in all cases, in particular in the case where line segments of the test geometry touches the polygon linework. In this case full topology must be computed. (However, if the test geometry consists of only points, this can be evaluated in an optimized fashion.

    • Field Detail

      • requireSomePointInInterior

        protected boolean requireSomePointInInterior
        This flag controls a difference between contains and covers. For contains the value is true. For covers the value is false.
      • hasSegmentIntersection

        private boolean hasSegmentIntersection
      • hasProperIntersection

        private boolean hasProperIntersection
      • hasNonProperIntersection

        private boolean hasNonProperIntersection
    • Constructor Detail

      • AbstractPreparedPolygonContains

        public AbstractPreparedPolygonContains​(PreparedPolygon prepPoly)
        Creates an instance of this operation.
        Parameters:
        prepPoly - the PreparedPolygon to evaluate
    • Method Detail

      • eval

        protected boolean eval​(Geometry geom)
        Evaluate the contains or covers relationship for the given geometry.
        Parameters:
        geom - the test geometry
        Returns:
        true if the test geometry is contained
      • isProperIntersectionImpliesNotContainedSituation

        private boolean isProperIntersectionImpliesNotContainedSituation​(Geometry testGeom)
      • isSingleShell

        private boolean isSingleShell​(Geometry geom)
        Tests whether a geometry consists of a single polygon with no holes.
        Returns:
        true if the geometry is a single polygon with no holes
      • findAndClassifyIntersections

        private void findAndClassifyIntersections​(Geometry geom)
      • fullTopologicalPredicate

        protected abstract boolean fullTopologicalPredicate​(Geometry geom)
        Computes the full topological predicate. Used when short-circuit tests are not conclusive.
        Parameters:
        geom - the test geometry
        Returns:
        true if this prepared polygon has the relationship with the test geometry