/**********************************************************************
*
* GEOS - Geometry Engine Open Source
* http://geos.osgeo.org
*
* Copyright (C) 2005-2006 Refractions Research Inc.
* Copyright (C) 2001-2002 Vivid Solutions Inc.
*
* This is free software; you can redistribute and/or modify it under
* the terms of the GNU Lesser General Public Licence as published
* by the Free Software Foundation.
* See the COPYING file for more information.
*
**********************************************************************
*
* Last port: geomgraph/Label.java r428 (JTS-1.12+)
*
**********************************************************************/
#pragma once
#include <geos/export.h>
#include <geos/geom/Location.h>
#include <geos/geomgraph/TopologyLocation.h>
#include <iosfwd> // for operator<<
#include <cassert>
namespace geos {
namespace geomgraph { // geos.geomgraph
/** \brief
* A <code>Label</code> indicates the topological relationship of a component
* of a topology graph to a given <code>Geometry</code>.
*
* This class supports labels for relationships to two <code>Geometry</code>s,
* which is sufficient for algorithms for binary operations.
*
* Topology graphs support the concept of labeling nodes and edges in the graph.
* The label of a node or edge specifies its topological relationship to one or
* more geometries. (In fact, since JTS operations have only two arguments labels
* are required for only two geometries). A label for a node or edge has one or
* two elements, depending on whether the node or edge occurs in one or both of the
* input <code>Geometry</code>s. Elements contain attributes which categorize the
* topological location of the node or edge relative to the parent
* <code>Geometry</code>; that is, whether the node or edge is in the interior,
* boundary or exterior of the <code>Geometry</code>. Attributes have a value
* from the set <code>{Interior, Boundary, Exterior}</code>. In a node each
* element has a single attribute <code><On></code>. For an edge each element has a
* triplet of attributes <code><Left, On, Right></code>.
*
* It is up to the client code to associate the 0 and 1 <code>TopologyLocation</code>s
* with specific geometries.
*
*/
class GEOS_DLL Label final {
public:
friend std::ostream& operator<< (std::ostream&, const Label&);
/** \brief
* Converts a Label to a Line label
* (that is, one with no side Locations)
*
*/
static Label toLineLabel(const Label& label)
{
Label lineLabel(geom::Location::NONE);
for(uint32_t i = 0; i < 2; i++) {
lineLabel.setLocation(i, label.getLocation(i));
}
return lineLabel;
};
/** \brief
* Construct a Label with a single location for both Geometries.
*/
Label(geom::Location onLoc)
: elt{TopologyLocation(onLoc)
, TopologyLocation(onLoc)}
{};
/** \brief
* Construct a Label with the location specified
* for the given Geometry.
*
* Other geometry location will be set to
* Location::NONE.
*/
Label(uint32_t geomIndex, geom::Location onLoc)
: elt{TopologyLocation(geom::Location::NONE)
, TopologyLocation(geom::Location::NONE)}
{
assert(geomIndex < 2);
elt[geomIndex].setLocation(onLoc);
};
/** \brief
* Construct a Label with On, Left and Right locations for both Geometries.
*
* Initialize the locations for both Geometries to the given values.
*/
Label(geom::Location onLoc, geom::Location leftLoc, geom::Location rightLoc)
: elt {TopologyLocation(onLoc, leftLoc, rightLoc)
, TopologyLocation(onLoc, leftLoc, rightLoc)}
{};
/// Copy ctor
Label(const Label& l)
: elt{TopologyLocation(l.elt[0])
, TopologyLocation(l.elt[1])}
{};
/** \brief
* Initialize both locations to Location::NONE
*
* isNull() should return true after this kind of construction
*/
Label()
: elt{TopologyLocation(geom::Location::NONE)
, TopologyLocation(geom::Location::NONE)}
{};
/** \brief
* Construct a Label with On, Left and Right locations for the
* given Geometries.
* Initialize the locations for the other Geometry to
* Location::NONE
*/
Label(uint32_t geomIndex, geom::Location onLoc, geom::Location leftLoc, geom::Location rightLoc)
{
elt[0] = TopologyLocation(geom::Location::NONE, geom::Location::NONE, geom::Location::NONE);
elt[1] = TopologyLocation(geom::Location::NONE, geom::Location::NONE, geom::Location::NONE);
elt[geomIndex].setLocations(onLoc, leftLoc, rightLoc);
};
Label&
operator=(const Label& l)
{
elt[0] = TopologyLocation(l.elt[0]);
elt[1] = TopologyLocation(l.elt[1]);
return *this;
};
void flip()
{
elt[0].flip();
elt[1].flip();
};
/** \brief
* Merge this label with another one.
*
* Merging updates any null attributes of this label with the attributes
* from lbl
*/
void merge(const Label& lbl)
{
for(int i = 0; i < 2; i++) {
elt[i].merge(lbl.elt[i]);
}
};
int getGeometryCount() const
{
int count = 0;
if(!elt[0].isNull()) {
count++;
}
if(!elt[1].isNull()) {
count++;
}
return count;
};
geom::Location getLocation(uint32_t geomIndex, uint32_t posIndex) const
{
assert(geomIndex < 2);
return elt[geomIndex].get(posIndex);
};
geom::Location getLocation(uint32_t geomIndex) const
{
assert(geomIndex < 2);
return elt[geomIndex].get(Position::ON);
};
void setLocation(uint32_t geomIndex, uint32_t posIndex, geom::Location location)
{
assert(geomIndex < 2);
elt[geomIndex].setLocation(posIndex, location);
};
void setLocation(uint32_t geomIndex, geom::Location location)
{
assert(geomIndex < 2);
elt[geomIndex].setLocation(Position::ON, location);
};
void setAllLocations(uint32_t geomIndex, geom::Location location)
{
assert(geomIndex < 2);
elt[geomIndex].setAllLocations(location);
};
void setAllLocationsIfNull(uint32_t geomIndex, geom::Location location)
{
assert(geomIndex < 2);
elt[geomIndex].setAllLocationsIfNull(location);
};
void setAllLocationsIfNull(geom::Location location)
{
setAllLocationsIfNull(0, location);
setAllLocationsIfNull(1, location);
};
bool isNull(uint32_t geomIndex) const
{
assert(geomIndex < 2);
return elt[geomIndex].isNull();
};
bool isNull() const
{
return elt[0].isNull() && elt[1].isNull();
};
bool isAnyNull(uint32_t geomIndex) const
{
assert(geomIndex < 2);
return elt[geomIndex].isAnyNull();
};
bool isArea() const
{
return elt[0].isArea() || elt[1].isArea();
};
bool isArea(uint32_t geomIndex) const
{
assert(geomIndex < 2);
return elt[geomIndex].isArea();
};
bool isLine(uint32_t geomIndex) const
{
assert(geomIndex < 2);
return elt[geomIndex].isLine();
};
bool isEqualOnSide(const Label& lbl, uint32_t side) const
{
return elt[0].isEqualOnSide(lbl.elt[0], side)
&& elt[1].isEqualOnSide(lbl.elt[1], side);
};
bool allPositionsEqual(uint32_t geomIndex, geom::Location loc) const
{
assert(geomIndex < 2);
return elt[geomIndex].allPositionsEqual(loc);
};
/** \brief
* Converts one GeometryLocation to a Line location
*/
void toLine(uint32_t geomIndex)
{
assert(geomIndex < 2);
if(elt[geomIndex].isArea()) {
elt[geomIndex] = TopologyLocation(elt[geomIndex].getLocations()[0]);
}
};
std::string toString() const;
private:
TopologyLocation elt[2];
};
std::ostream& operator<< (std::ostream&, const Label&);
} // namespace geos.geomgraph
} // namespace geos