polygon.cpp

来自「一个很好的vc底层代码」· C++ 代码 · 共 346 行

/**********************************************************************
 * $Id: Polygon.cpp,v 1.45.2.1 2005/05/24 07:29:36 strk Exp $
 *
 * GEOS - Geometry Engine Open Source
 * http://geos.refractions.net
 *
 * Copyright (C) 2001-2002 Vivid Solutions Inc.
 * Copyright (C) 2005 Refractions Research 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.
 *
 **********************************************************************/

#include <geos/geom.h>
#include <typeinfo>
#include <geos/geosAlgorithm.h>

namespace geos {

Polygon::Polygon(const Polygon &p): Geometry(p.getFactory()){
	shell=new LinearRing(*p.shell);
	holes=new vector<Geometry *>();
	for(int i=0;i<(int)p.holes->size();i++) {
		LinearRing *h=new LinearRing(* (LinearRing*)(*p.holes)[i]);
		holes->push_back(h);
	}
}

/*
* Constructs a <code>Polygon</code> with the given exterior
* and interior boundaries.
*
* @param  shell     the outer boundary of the new <code>Polygon</code>,
*                   or <code>null</code> or an empty
*                   <code>LinearRing</code> if the empty geometry
*                   is to be created.
*
* @param  holes     the <code>LinearRings</code> defining the inner
*                   boundaries of the new <code>Polygon</code>, or
*                   <code>null</code> or empty <code>LinearRing</code>s
*                   if the empty  geometry is to be created.
*
* Polygon will take ownership of Shell and Holes LinearRings
*
*/
Polygon::Polygon(LinearRing *newShell, vector<Geometry *> *newHoles, const GeometryFactory *newFactory): Geometry(newFactory)
{
	if (newShell==NULL) {
		shell=getFactory()->createLinearRing(NULL);
	}
	else
	{
		if (newShell->isEmpty() && hasNonEmptyElements(newHoles)) {
			delete newShell;
			delete newHoles;
			throw new IllegalArgumentException("shell is empty but holes are not");
		}
		shell=newShell;
	}

	if (newHoles==NULL)
	{
		holes=new vector<Geometry *>();
	}
	else
	{
		if (hasNullElements(newHoles)) {
			delete newShell;
			delete newHoles;
			throw new IllegalArgumentException("holes must not contain null elements");
		}
		for (unsigned int i=0; i<newHoles->size(); i++)
			if ( (*newHoles)[i]->getGeometryTypeId() != GEOS_LINEARRING)
				throw new IllegalArgumentException("holes must be LinearRings");
		holes=newHoles;
	}
}

Geometry *Polygon::clone() const {
	return new Polygon(*this);
}

CoordinateSequence* Polygon::getCoordinates() const {
	if (isEmpty()) {
		return getFactory()->getCoordinateSequenceFactory()->create(NULL);
	}

	vector<Coordinate> *cl = new vector<Coordinate>;

	int k = -1;
	const CoordinateSequence* shellCoords=shell->getCoordinatesRO();
	for (int x = 0; x < shellCoords->getSize(); x++) {
		k++;
		cl->push_back(shellCoords->getAt(x));
	}

	for (unsigned int i = 0; i < holes->size(); i++) {
		const CoordinateSequence* childCoords=((LinearRing *)(*holes)[i])->getCoordinatesRO();
		for (int j = 0; j < childCoords->getSize(); j++) {
			k++;
			cl->push_back(childCoords->getAt(j));
		}
	}

	return getFactory()->getCoordinateSequenceFactory()->create(cl);
}

int Polygon::getNumPoints() const {
	int numPoints = shell->getNumPoints();
	for (unsigned int i = 0; i < holes->size(); i++) {
		numPoints += ((LinearRing *)(*holes)[i])->getNumPoints();
	}
	return numPoints;
}

int Polygon::getDimension() const {
	return 2;
}

int Polygon::getBoundaryDimension() const {
	return 1;
}

bool Polygon::isEmpty() const {
	return shell->isEmpty();
}

bool Polygon::isSimple() const {
	return true;
}

const LineString* Polygon::getExteriorRing() const {
	return shell;
}

int Polygon::getNumInteriorRing() const {
	return (int)holes->size();
}

const LineString* Polygon::getInteriorRingN(int n) const {
	return (LineString *) (*holes)[n];
}

string Polygon::getGeometryType() const {
	return "Polygon";
}

// Returns a newly allocated Geometry object
Geometry* Polygon::getBoundary() const {
	if (isEmpty()) {
		return getFactory()->createGeometryCollection(NULL);
	}
	if ( ! holes->size() )
	{
		return new LineString(*shell);
	}

	vector<Geometry *> *rings = new vector<Geometry *>(holes->size()+1);
	(*rings)[0]=new LineString(*shell);
	for (unsigned int i=0; i<holes->size(); i++) {
		(*rings)[i + 1] = new LineString((const LineString &)*(*holes)[i]);
	}
	MultiLineString *ret = getFactory()->createMultiLineString(rings);
	return ret;
}

Envelope* Polygon::computeEnvelopeInternal() const {
	return new Envelope(*(shell->getEnvelopeInternal()));
}

bool Polygon::equalsExact(const Geometry *other, double tolerance) const {
	if (!isEquivalentClass(other)) {
		return false;
	}
	const Polygon* otherPolygon=dynamic_cast<const Polygon*>(other);
	if (typeid(*(otherPolygon->shell))!=typeid(Geometry)) {
		return false;
	}
	Geometry* otherPolygonShell=dynamic_cast<Geometry *>(otherPolygon->shell);
	if (!shell->equalsExact(otherPolygonShell, tolerance)) {
		return false;
	}
	if (holes->size()!=otherPolygon->holes->size()) {
		return false;
	}
	for (unsigned int i = 0; i < holes->size(); i++) {
		if (!((LinearRing *)(*holes)[i])->equalsExact((*(otherPolygon->holes))[i],tolerance)) {
			return false;
		}
	}
	return true;
}

void Polygon::apply_ro(CoordinateFilter *filter) const {
	shell->apply_ro(filter);
	for (unsigned int i = 0; i < holes->size(); i++) {
		((LinearRing *)(*holes)[i])->apply_ro(filter);
	}
}

void Polygon::apply_rw(CoordinateFilter *filter) {
	shell->apply_rw(filter);
	for (unsigned int i = 0; i < holes->size(); i++) {
		((LinearRing *)(*holes)[i])->apply_rw(filter);
	}
}

void Polygon::apply_rw(GeometryFilter *filter) {
	filter->filter_rw(this);
}

void Polygon::apply_ro(GeometryFilter *filter) const {
	filter->filter_ro(this);
}

Geometry* Polygon::convexHull() const {
	return getExteriorRing()->convexHull();
}

void Polygon::normalize() {
	normalize(shell, true);
	for (unsigned int i = 0; i < holes->size(); i++) {
		normalize((LinearRing *)(*holes)[i], false);
	}
	sort(holes->begin(),holes->end(),greaterThen);
}

int Polygon::compareToSameClass(const Geometry *p) const {
	return shell->compareToSameClass(((Polygon*)p)->shell);
}

void Polygon::normalize(LinearRing *ring, bool clockwise) {
	if (ring->isEmpty()) {
		return;
	}
	CoordinateSequence* uniqueCoordinates=ring->getCoordinates();
	uniqueCoordinates->deleteAt(uniqueCoordinates->getSize()-1);
	const Coordinate* minCoordinate=CoordinateSequence::minCoordinate(uniqueCoordinates);
	CoordinateSequence::scroll(uniqueCoordinates, minCoordinate);
	uniqueCoordinates->add(uniqueCoordinates->getAt(0));
	if (CGAlgorithms::isCCW(uniqueCoordinates)==clockwise) {
		CoordinateSequence::reverse(uniqueCoordinates);
	}
	ring->setPoints(uniqueCoordinates);
	delete(uniqueCoordinates);
}

const Coordinate* Polygon::getCoordinate() const {
	return shell->getCoordinate();
}

/*
*  Returns the area of this <code>Polygon</code>
*
*@return the area of the polygon
*/
double Polygon::getArea() const {
	double area=0.0;
	area+=fabs(CGAlgorithms::signedArea(shell->getCoordinatesRO()));
	for(unsigned int i=0;i<holes->size();i++) {
		CoordinateSequence *h=(*holes)[i]->getCoordinates();
        	area-=fabs(CGAlgorithms::signedArea(h));
		delete h;
	}
	return area;
}

/**
 * Returns the perimeter of this <code>Polygon</code>
 *
 * @return the perimeter of the polygon
 */
double Polygon::getLength() const {
	double len=0.0;
	len+=shell->getLength();
	for(unsigned int i=0;i<holes->size();i++) {
        len+=(*holes)[i]->getLength();
	}
	return len;
}

void Polygon::apply_ro(GeometryComponentFilter *filter) const {
	filter->filter_ro(this);
	shell->apply_ro(filter);
	for(unsigned int i=0;i<holes->size();i++) {
        	(*holes)[i]->apply_ro(filter);
	}
}

void Polygon::apply_rw(GeometryComponentFilter *filter) {
	filter->filter_rw(this);
	shell->apply_rw(filter);
	for(unsigned int i=0;i<holes->size();i++) {
        	(*holes)[i]->apply_rw(filter);
	}
}

Polygon::~Polygon(){
	delete shell;
	for(int i=0;i<(int)holes->size();i++) {
		delete (*holes)[i];
	}
	delete holes;
}
GeometryTypeId
Polygon::getGeometryTypeId() const {
	return GEOS_POLYGON;
}

} // namespace geos

/**********************************************************************
 * $Log: Polygon.cpp,v $
 * Revision 1.45.2.1  2005/05/24 07:29:36  strk
 * Fixed polygon::getBoundary() to never return (MULTI)LinearRings.
 *
 * Revision 1.45  2004/12/08 13:54:43  strk
 * gcc warnings checked and fixed, general cleanups.
 *
 * Revision 1.44  2004/11/12 18:12:05  strk
 * Changed ::getBoundary() to return LineString if polygon has no holes.
 * (has required to pass OGC conformance test T20)
 *
 * Revision 1.43  2004/07/27 16:35:46  strk
 * Geometry::getEnvelopeInternal() changed to return a const Envelope *.
 * This should reduce object copies as once computed the envelope of a
 * geometry remains the same.
 *
 * Revision 1.42  2004/07/22 07:04:49  strk
 * Documented missing geometry functions.
 *
 * Revision 1.41  2004/07/13 08:33:52  strk
 * Added missing virtual destructor to virtual classes.
 * Fixed implicit unsigned int -> int casts
 *
 * Revision 1.40  2004/07/08 19:34:49  strk
 * Mirrored JTS interface of CoordinateSequence, factory and
 * default implementations.
 * Added DefaultCoordinateSequenceFactory::instance() function.
 *
 **********************************************************************/