Package org.locationtech.spatial4j.shape.impl

Class BufferedLine

java.lang.Object
org.locationtech.spatial4j.shape.BaseShape<SpatialContext>
org.locationtech.spatial4j.shape.impl.BufferedLine
All Implemented Interfaces:
Shape
public class BufferedLine extends BaseShape<SpatialContext>
INTERNAL: A line between two points with a buffer distance extending in every direction. By contrast, an un-buffered line covers no area and as such is extremely unlikely to intersect with a point. BufferedLine isn't yet aware of geodesics (e.g. the anti-meridian); it operates in Euclidean space.

  • Field Details

    • pA

      private final Point pA

    • pB

      private final Point pB

    • buf

      private final double buf

    • bbox

      private final Rectangle bbox

    • linePrimary

      private final InfBufLine linePrimary
      the primary line; passes through pA invalid input: '&' pB

    • linePerp

      private final InfBufLine linePerp
      perpendicular to the primary line, centered between pA invalid input: '&' pB

  • Constructor Details

    • BufferedLine

      public BufferedLine(Point pA, Point pB, double buf, SpatialContext ctx)
      Creates a buffered line from pA to pB. The buffer extends on both sides of the line, making the width 2x the buffer. The buffer extends out from pA & pB, making the line in effect 2x the buffer longer than pA to pB.
      Parameters:
      pA - start point
      pB - end point
      buf - the buffer distance in degrees

  • Method Details

    • isEmpty

      public boolean isEmpty()
      Description copied from interface: Shape
      Shapes can be "empty", which is to say it exists nowhere. The underlying coordinates are typically NaN.

    • getBuffered

      public Shape getBuffered(double distance, SpatialContext ctx)
      Description copied from interface: Shape
      Returns a buffered version of this shape. The buffer is usually a rounded-corner buffer, although some shapes might buffer differently. This is an optional operation.
      Returns:
      Not null, and the returned shape should contain the current shape.

    • expandBufForLongitudeSkew

      public static double expandBufForLongitudeSkew(Point pA, Point pB, double buf)
      Calls DistanceUtils.calcLonDegreesAtLat(double, double) given pA or pB's latitude; whichever is farthest. It's useful to expand a buffer of a line segment when used in a geospatial context to cover the desired area.

    • relate

      public SpatialRelation relate(Shape other)
      Description copied from interface: Shape
      Describe the relationship between the two objects. For example
      • this is WITHIN other
      • this CONTAINS other
      • this is DISJOINT other
      • this INTERSECTS other
      Note that a Shape implementation may choose to return INTERSECTS when the true answer is WITHIN or CONTAINS for performance reasons. If a shape does this then it must document when it does. Ideally the shape will not do this approximation in all circumstances, just sometimes.

      If the shapes are equal then the result is CONTAINS (preferred) or WITHIN.

    • relate

      public SpatialRelation relate(Rectangle r)

    • contains

      public boolean contains(Point p)

    • getBoundingBox

      public Rectangle getBoundingBox()
      Description copied from interface: Shape
      Get the bounding box for this Shape. This means the shape is within the bounding box and that it touches each side of the rectangle.

      Postcondition: this.getBoundingBox().relate(this) == CONTAINS

    • hasArea

      public boolean hasArea()
      Description copied from interface: Shape
      Does the shape have area? This will be false for points and lines. It will also be false for shapes that normally have area but are constructed in a degenerate case as to not have area (e.g. a circle with 0 radius or rectangle with no height or no width).

    • getArea

      public double getArea(SpatialContext ctx)
      Description copied from interface: Shape
      Calculates the area of the shape, in square-degrees. If ctx is null then simple Euclidean calculations will be used. This figure can be an estimate.

    • getCenter

      public Point getCenter()
      Description copied from interface: Shape
      Returns the center point of this shape. This is usually the same as getBoundingBox().getCenter() but it doesn't have to be.

      Postcondition: this.relate(this.getCenter()) == CONTAINS

    • getA

      public Point getA()

    • getB

      public Point getB()

    • getBuf

      public double getBuf()

    • getLinePrimary

      public InfBufLine getLinePrimary()
      INTERNAL

    • getLinePerp

      public InfBufLine getLinePerp()
      INTERNAL

    • toString

      public String toString()
      Overrides:
      toString in class Object

    • equals

      public boolean equals(Object o)
      Description copied from interface: Shape
      The sub-classes of Shape generally implement the same contract for Object.equals(Object) and Object.hashCode() amongst the same sub-interface type. This means, for example, that multiple Point implementations of different classes are equal if they share the same x & y.
      Specified by:
      equals in interface Shape
      Overrides:
      equals in class Object

    • hashCode

      public int hashCode()
      Overrides:
      hashCode in class Object