geos::CoordinateSequence Class Reference

The internal representation of a list of coordinates inside a Geometry. More...

#include <geos.h>

Inheritance diagram for geos::CoordinateSequence:

geos::DefaultCoordinateSequence List of all members.

Public Types

enum  
 Standard ordinate index values.

Public Member Functions

virtual CoordinateSequenceclone () const=0
 Returns a deep copy of this collection.
virtual const CoordinategetAt (int i) const=0
 Returns a read-only reference to Coordinate at position i.
virtual int getSize () const=0
 Returns the number of Coordinates (actual or otherwise, as this implementation may not store its data in Coordinate objects).
virtual const vector< Coordinate > * toVector () const=0
 Returns a read-only vector with the Coordinates in this collection.
void add (const vector< Coordinate > *vc, bool allowRepeated)
 Add an array of coordinates.
void add (const CoordinateSequence *cl, bool allowRepeated, bool direction)
 Add an array of coordinates.
void add (const Coordinate &c, bool allowRepeated)
 Add a coordinate.
virtual bool isEmpty () const=0
 Returns true it list contains no coordinates.
virtual void add (const Coordinate &c)=0
 Add a Coordinate to the list.
virtual void setAt (const Coordinate &c, int pos)=0
 Copy Coordinate c to position pos.
virtual void deleteAt (int pos)=0
 Delete Coordinate at position pos (list will shrink).
virtual string toString () const=0
 Get a string rapresentation of CoordinateSequence.
virtual void setPoints (const vector< Coordinate > &v)=0
 Substitute Coordinate list with a copy of the given vector.
bool hasRepeatedPoints () const
 Returns true if contains any two consecutive points.
const CoordinateminCoordinate () const
 Returns lower-left Coordinate in list.
virtual unsigned int getDimension () const=0
 Get number of dimensions.

Static Public Member Functions

static CoordinateSequenceremoveRepeatedPoints (const CoordinateSequence *cl)
 Returns a new CoordinateSequence being a copy of the input with any consecutive equal Coordinate removed.
static bool hasRepeatedPoints (const CoordinateSequence *cl)
 Returns true if given CoordinateSequence contains any two consecutive Coordinate.
static CoordinateSequenceatLeastNCoordinatesOrNothing (int n, CoordinateSequence *c)
 Returns either the given CoordinateSequence if its length is greater than the given amount, or an empty CoordinateSequence.
static const CoordinateminCoordinate (CoordinateSequence *cl)
 Returns lower-left Coordinate in given CoordinateSequence. This is actually the Coordinate with lower X (and Y if needed) ordinate.
static int indexOf (const Coordinate *coordinate, const CoordinateSequence *cl)
 Return position of a Coordinate, or -1 if not found.
static bool equals (CoordinateSequence *cl1, CoordinateSequence *cl2)
 Returns true if the two arrays are identical, both null, or pointwise equal.
static void scroll (CoordinateSequence *cl, const Coordinate *firstCoordinate)
 Scroll given CoordinateSequence so to start with given Coordinate.
static void reverse (CoordinateSequence *cl)
 Reverse Coordinate order in given CoordinateSequence.

Detailed Description

The internal representation of a list of coordinates inside a Geometry.

There are some cases in which you might want Geometries to store their points using something other than the GEOS Coordinate class. For example, you may want to experiment with another implementation, such as an array of Xs and an array of Ys. or you might want to use your own coordinate class, one that supports extra attributes like M-values.

You can do this by implementing the CoordinateSequence and CoordinateSequenceFactory interfaces. You would then create a GeometryFactory parameterized by your CoordinateSequenceFactory, and use this GeometryFactory to create new Geometries. All of these new Geometries will use your CoordinateSequence implementation.


Member Function Documentation

virtual const Coordinate& geos::CoordinateSequence::getAt ( int  i  )  const [pure virtual]

Returns a read-only reference to Coordinate at position i.

Whether or not the Coordinate returned is the actual underlying Coordinate or merely a copy depends on the implementation.

Implemented in geos::DefaultCoordinateSequence.

virtual const vector<Coordinate>* geos::CoordinateSequence::toVector (  )  const [pure virtual]

Returns a read-only vector with the Coordinates in this collection.

Whether or not the Coordinates returned are the actual underlying Coordinates or merely copies depends on the implementation. Note that if this implementation does not store its data as an array of Coordinates, this method will incur a performance penalty because the array needs to be built from scratch.

Implemented in geos::DefaultCoordinateSequence.

void geos::CoordinateSequence::add ( const vector< Coordinate > *  vc,
bool  allowRepeated 
)

Add an array of coordinates.

Parameters:
vc The coordinates
allowRepeated if set to false, repeated coordinates are collapsed
Returns:
true (as by general collection contract)

void geos::CoordinateSequence::add ( const CoordinateSequence cl,
bool  allowRepeated,
bool  direction 
)

Add an array of coordinates.

Parameters:
cl The coordinates
allowRepeated if set to false, repeated coordinates are collapsed
direction if false, the array is added in reverse order
Returns:
true (as by general collection contract)

void geos::CoordinateSequence::add ( const Coordinate c,
bool  allowRepeated 
)

Add a coordinate.

Parameters:
c The coordinate to add
allowRepeated if set to false, repeated coordinates are collapsed
Returns:
true (as by general collection contract)

CoordinateSequence * geos::CoordinateSequence::removeRepeatedPoints ( const CoordinateSequence cl  )  [static]

Returns a new CoordinateSequence being a copy of the input with any consecutive equal Coordinate removed.

This function allocates space for a CoordinateSequence object being a copy of the input once with consecutive equal points removed.


The documentation for this class was generated from the following files:
Generated on Mon Jan 8 23:49:01 2007 for GEOS by  doxygen 1.5.1