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Module geom reference

by Victor Acevedo last modified 2012-12-14 17:58

geom module contains utilities to manage geometries

Note

To get more information about Geometry methods see Geometry javadoc

Commons geometries methods

Interface Geometry: This interface is equivalent to the GM_Object specified in ISO 19107. A geometric object shall be a combination of a coordinate geometry and a coordinate reference system.

  • area(): Return geometry area
  • buffer(distance): Computes a buffer area around this geometry having the given width
  • centroid(): Return geometry centroid
  • distance(geometry): Returns the minimum distance between this Geometry and the specified geometry.
  • getEnvelope(): Returns the minimum bounding box for this Geometry.
  • getGeometryType(): Instance of the GeometryType associated to this geometry
  • getDimension(): Returns the largest number n such that each direct position in a geometric set can be associated with a subset that has the direct position in its interior and is similar (isomorphic) to Rn, Euclidean n-space

Geometry types

Point

This interface is equivalent to the GM_Point specified in ISO 19107. It is one of the basic data type for a geometric object consisting of one and only one point. They do not have volume, area, length, or any other higher-dimensional analogue.

  • getX(): Returns the X coordinate
  • getY(): Returns the Y coordinate
  • getCoordinateAt(dimension): Gets the coordinate in a concrete dimension
    • param dimension: Dimension coordinate to get
    • type dimension: integer
    • allowed values: 0=X, 1=Y, 2=Z
  • setX(value): Sets the X coordinate
    • param value: Value of the dimension X
    • type value: double
  • setY(value): Sets the Y coordinate
    • param value: Value of the dimension Y
    • type value: double
  • setCoordinateAt(dimension, value): Sets a ordinate in a concrete dimension
    • param dimension: Dimension coordinate to set
    • type dimension: integer
    • param value: Value of the dimension
    • type value: double

Line

This interface is equivalent to the GM_OrientableCurve specified in ISO 19107. Curves are continuous, connected, and have a measurable length in terms of the coordinate system.

  • addVertex(point): Adds a vertex to the curve
    • param point: Point to addLayer
    • type: Point
  • getNumVertices(): Gets the number of vertex of the curve
  • getVertex(index): Gets a vertex
    • param index: Geometry vertex index
    • type index: integer

Polygon

This interface is equivalent to the GM_Surface specified in ISO 19107. This is the basis for 2-dimensional geometry

  • addVertex(point): Adds a vertex to the curve
    • param point: Point to addLayer
    • type: Point
  • getNumVertices(): Gets the number of vertex of the curve
  • getVertex(index): Gets a vertex
    • param index: Geometry vertex index
    • type index: integer
  • getSurfaceAppearance(): Gets surface appearance
  • setSurfaceAppearance(appearance): Sets surface appearance

Multigeometry

This interface is equivalent to the GM_Aggregate specified in ISO 19107

  • getPrimitiveAt(int i): Returns one of the Primitive's that is in a concrete position. - param i: geometry position - type i: integer
  • getPrimitivesNumber(): Returns the number of Primitive's that composes this multi geometry.

Geometry util functions

  • createGeometry(type[, subtype]): Create a new geometry with a concrete type and subtype
    • param type: geometry type
    • type type: integer
    • param subtype: (Optional) geometry subtype
    • type type: integer
    • return: geometry
    • rtype: Geometry
  • createPoint([x][, y][, subtype]): Create a new point with a subtype dimensions and sets the value for 'X' and 'Y' coordinates. If is used without parameters will return new Point2D with (0,0) coordinates
    • param x:(Optional) X coordinate value
    • type x: double
    • param y:(Optional) Y coordinate value
    • type y: double
    • param subtype: (Optional) geometry dimensions
    • type: integer
    • return: Point
    • rtype: Point
  • createMultiPoint(points[, subtype]): Create a new multipoint with a subtype from a list values of X and Y like ([x1, y1], [x2, y2], ...., [xn, yn])
    • param points: list of tuples with X and Y values
    • type points: list
    • param subtype: (Optional) geometry dimensions
    • type: integer
    • return: multipoint
    • rtype: multipoint

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