File: Polygonizer.cpp

package info (click to toggle)
geos 3.4.2-6
  • links: PTS, VCS
  • area: main
  • in suites: jessie, jessie-kfreebsd
  • size: 16,572 kB
  • ctags: 13,989
  • sloc: cpp: 97,030; xml: 32,337; sh: 10,379; ansic: 3,726; php: 1,831; makefile: 1,619; ruby: 1,295; python: 928
file content (314 lines) | stat: -rw-r--r-- 7,156 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
/**********************************************************************
 *
 * GEOS - Geometry Engine Open Source
 * http://geos.osgeo.org
 *
 * Copyright (C) 2010 Sandro Santilli <strk@keybit.net>
 * 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: operation/polygonize/Polygonizer.java rev. 1.6 (JTS-1.10)
 *
 **********************************************************************/

#include <geos/operation/polygonize/Polygonizer.h>
#include <geos/operation/polygonize/PolygonizeGraph.h>
#include <geos/operation/polygonize/EdgeRing.h>
#include <geos/geom/LineString.h>
#include <geos/geom/Geometry.h>
#include <geos/geom/Polygon.h>
// std
#include <vector>

#ifdef _MSC_VER
#pragma warning(disable:4355)
#endif

#ifndef GEOS_DEBUG
#define GEOS_DEBUG 0
#endif

using namespace std;
using namespace geos::geom;

namespace geos {
namespace operation { // geos.operation
namespace polygonize { // geos.operation.polygonize

Polygonizer::LineStringAdder::LineStringAdder(Polygonizer *p):
	pol(p)
{
}

void
Polygonizer::LineStringAdder::filter_ro(const Geometry *g)
{
	const LineString *ls = dynamic_cast<const LineString *>(g);
	if ( ls ) pol->add(ls);
}


/*
 * Create a polygonizer with the same GeometryFactory
 * as the input Geometry
 */
Polygonizer::Polygonizer():
	lineStringAdder(this), 
	graph(NULL),
	dangles(),
	cutEdges(),
	invalidRingLines(),
	holeList(),
	shellList(),
	polyList(NULL)
{
}

Polygonizer::~Polygonizer()
{
	delete graph;

	for (unsigned int i=0, n=invalidRingLines.size(); i<n; ++i)
		delete invalidRingLines[i];

	if ( polyList )
	{
		for (unsigned int i=0, n=polyList->size(); i<n; ++i)
			delete (*polyList)[i];
		delete polyList;
	}
}

/*
 * Add a collection of geometries to be polygonized.
 * May be called multiple times.
 * Any dimension of Geometry may be added;
 * the constituent linework will be extracted and used
 *
 * @param geomList a list of {@link Geometry}s with linework to be polygonized
 */
void
Polygonizer::add(vector<Geometry*> *geomList)
{
	for(unsigned int i=0, n=geomList->size(); i<n; ++i)
	{
		const Geometry *geometry=(*geomList)[i];
		add(geometry);
	}
}

/*
 * Add a collection of geometries to be polygonized.
 * May be called multiple times.
 * Any dimension of Geometry may be added;
 * the constituent linework will be extracted and used
 *
 * @param geomList a list of {@link Geometry}s with linework to be polygonized
 */
void
Polygonizer::add(vector<const Geometry*> *geomList)
{
	for(unsigned int i=0, n=geomList->size(); i<n; ++i)
	{
		const Geometry *geometry=(*geomList)[i];
		add(geometry);
	}
}

/*
 * Add a geometry to the linework to be polygonized.
 * May be called multiple times.
 * Any dimension of Geometry may be added;
 * the constituent linework will be extracted and used
 *
 * @param g a Geometry with linework to be polygonized
 */
void
Polygonizer::add(Geometry *g)
{
	g->apply_ro(&lineStringAdder);
}

/*
 * Add a geometry to the linework to be polygonized.
 * May be called multiple times.
 * Any dimension of Geometry may be added;
 * the constituent linework will be extracted and used
 *
 * @param g a Geometry with linework to be polygonized
 */
void
Polygonizer::add(const Geometry *g)
{
	g->apply_ro(&lineStringAdder);
}

/*
 * Add a linestring to the graph of polygon edges.
 *
 * @param line the LineString to add
 */
void
Polygonizer::add(const LineString *line)
{
	// create a new graph using the factory from the input Geometry
	if (graph==NULL)
		graph=new PolygonizeGraph(line->getFactory());
	graph->addEdge(line);
}

/*
 * Gets the list of polygons formed by the polygonization.
 * @return a collection of Polygons
 */
vector<Polygon*>*
Polygonizer::getPolygons()
{
	polygonize();
	vector<Polygon *> *ret = polyList;
	polyList = NULL;
	return ret;
}

/* public */
const vector<const LineString*>&
Polygonizer::getDangles()
{
	polygonize();
	return dangles;
}

/* public */
const vector<const LineString*>&
Polygonizer::getCutEdges()
{
	polygonize();
	return cutEdges;
}

/* public */
const vector<LineString*>&
Polygonizer::getInvalidRingLines()
{
	polygonize();
	return invalidRingLines;
}

/* public */
void
Polygonizer::polygonize()
{
	// check if already computed
	if (polyList!=NULL) return;

	polyList=new vector<Polygon*>();

	// if no geometries were supplied it's possible graph could be null
	if (graph==NULL) return; 

	graph->deleteDangles(dangles);

	graph->deleteCutEdges(cutEdges);

	vector<EdgeRing*> edgeRingList;
	graph->getEdgeRings(edgeRingList);
#if GEOS_DEBUG
	cerr<<"Polygonizer::polygonize(): "<<edgeRingList.size()<<" edgeRings in graph"<<endl;
#endif
	vector<EdgeRing*> validEdgeRingList;
	invalidRingLines.clear(); /* what if it was populated already ? we should clean ! */
	findValidRings(edgeRingList, validEdgeRingList, invalidRingLines);
#if GEOS_DEBUG
	cerr<<"                           "<<validEdgeRingList.size()<<" valid"<<endl;
	cerr<<"                           "<<invalidRingLines.size()<<" invalid"<<endl;
#endif

	findShellsAndHoles(validEdgeRingList);
#if GEOS_DEBUG
	cerr<<"                           "<<holeList.size()<<" holes"<<endl;
	cerr<<"                           "<<shellList.size()<<" shells"<<endl;
#endif

	assignHolesToShells(holeList, shellList);

	for (unsigned int i=0, n=shellList.size(); i<n; ++i)
	{
		EdgeRing *er=shellList[i];
		polyList->push_back(er->getPolygon());
	}
}

/* private */
void
Polygonizer::findValidRings(const vector<EdgeRing*>& edgeRingList,
	vector<EdgeRing*>& validEdgeRingList,
	vector<LineString*>& invalidRingList)
{
	typedef vector<EdgeRing*> EdgeRingList;
	
	for (EdgeRingList::size_type i=0, n=edgeRingList.size(); i<n; ++i)
	{
		EdgeRing *er = edgeRingList[i];
		if (er->isValid())
		{
			validEdgeRingList.push_back(er);
		}
		else
		{
			// NOTE: polygonize::EdgeRing::getLineString
			// returned LineString ownership is transferred.
			invalidRingList.push_back(er->getLineString());
		}
	}
}

/* private */
void
Polygonizer::findShellsAndHoles(const vector<EdgeRing*>& edgeRingList)
{
	holeList.clear(); 
	shellList.clear();
	for (unsigned int i=0, n=edgeRingList.size(); i<n; ++i)
	{
		EdgeRing *er=edgeRingList[i];
		if (er->isHole())
			holeList.push_back(er);
		else
			shellList.push_back(er);
	}
}

/* private */
void
Polygonizer::assignHolesToShells(const vector<EdgeRing*>& holeList, vector<EdgeRing*>& shellList)
{
	for (unsigned int i=0, n=holeList.size(); i<n; ++i)
	{
		EdgeRing *holeER=holeList[i];
		assignHoleToShell(holeER, shellList);
	}
}

/* private */
void
Polygonizer::assignHoleToShell(EdgeRing *holeER,
		vector<EdgeRing*>& shellList)
{
	EdgeRing *shell = EdgeRing::findEdgeRingContaining(holeER, &shellList);

	if (shell!=NULL)
		shell->addHole(holeER->getRingOwnership());
}


} // namespace geos.operation.polygonize
} // namespace geos.operation
} // namespace geos