GEOS 3.12.0
UnaryUnionOp.h
1/**********************************************************************
2 *
3 * GEOS - Geometry Engine Open Source
4 * http://geos.osgeo.org
5 *
6 * Copyright (C) 2011 Sandro Santilli <strk@kbt.io>
7 *
8 * This is free software; you can redistribute and/or modify it under
9 * the terms of the GNU Lesser General Public Licence as published
10 * by the Free Software Foundation.
11 * See the COPYING file for more information.
12 *
13 **********************************************************************
14 *
15 * Last port: operation/union/UnaryUnionOp.java r320 (JTS-1.12)
16 *
17 **********************************************************************/
18
19#pragma once
20
21#include <memory>
22#include <vector>
23
24#include <geos/export.h>
25#include <geos/geom/GeometryFactory.h>
26#include <geos/geom/Point.h>
27#include <geos/geom/LineString.h>
28#include <geos/geom/Polygon.h>
29#include <geos/geom/util/GeometryExtracter.h>
30#include <geos/operation/union/CascadedPolygonUnion.h>
31
32#ifdef _MSC_VER
33#pragma warning(push)
34#pragma warning(disable: 4251) // warning C4251: needs to have dll-interface to be used by clients of class
35#endif
36
37// Forward declarations
38namespace geos {
39namespace geom {
40class GeometryFactory;
41class Geometry;
42}
43}
44
45namespace geos {
46namespace operation { // geos::operation
47namespace geounion { // geos::operation::geounion
48
86class GEOS_DLL UnaryUnionOp {
87public:
88
89 template <typename T>
90 static std::unique_ptr<geom::Geometry>
91 Union(const T& geoms)
92 {
93 UnaryUnionOp op(geoms);
94 return op.Union();
95 }
96
97 template <class T>
98 static std::unique_ptr<geom::Geometry>
99 Union(const T& geoms,
100 geom::GeometryFactory& geomFact)
101 {
102 UnaryUnionOp op(geoms, geomFact);
103 return op.Union();
104 }
105
106 static std::unique_ptr<geom::Geometry>
107 Union(const geom::Geometry& geom)
108 {
109 UnaryUnionOp op(geom);
110 return op.Union();
111 }
112
113 template <class T>
114 UnaryUnionOp(const T& geoms, geom::GeometryFactory& geomFactIn)
115 : geomFact(&geomFactIn)
116 , unionFunction(&defaultUnionFunction)
117 {
118 extractGeoms(geoms);
119 }
120
121 template <class T>
122 UnaryUnionOp(const T& geoms)
123 : geomFact(nullptr)
124 , unionFunction(&defaultUnionFunction)
125 {
126 extractGeoms(geoms);
127 }
128
129 UnaryUnionOp(const geom::Geometry& geom)
130 : geomFact(geom.getFactory())
131 , unionFunction(&defaultUnionFunction)
132 {
133 extract(geom);
134 }
135
136 void setUnionFunction(UnionStrategy* unionFun)
137 {
138 unionFunction = unionFun;
139 }
140
151 std::unique_ptr<geom::Geometry> Union();
152
153private:
154
155 template <typename T>
156 void
157 extractGeoms(const T& geoms)
158 {
159 for(typename T::const_iterator
160 i = geoms.begin(),
161 e = geoms.end();
162 i != e;
163 ++i) {
164 const geom::Geometry* geom = *i;
165 extract(*geom);
166 }
167 }
168
169 void
170 extract(const geom::Geometry& geom)
171 {
172 using namespace geom::util;
173
174 if(! geomFact) {
175 geomFact = geom.getFactory();
176 }
177
178 GeometryExtracter::extract<geom::Polygon>(geom, polygons);
179 GeometryExtracter::extract<geom::LineString>(geom, lines);
180 GeometryExtracter::extract<geom::Point>(geom, points);
181 }
182
195 std::unique_ptr<geom::Geometry>
196 unionNoOpt(const geom::Geometry& g0)
197 {
198 if(! empty.get()) {
199 empty = geomFact->createEmptyGeometry();
200 }
201 return unionFunction->Union(&g0, empty.get());
202 }
203
213 std::unique_ptr<geom::Geometry> unionWithNull(
214 std::unique_ptr<geom::Geometry> g0,
215 std::unique_ptr<geom::Geometry> g1
216 );
217
218 // Members
219 std::vector<const geom::Polygon*> polygons;
220 std::vector<const geom::LineString*> lines;
221 std::vector<const geom::Point*> points;
222
223 const geom::GeometryFactory* geomFact;
224 std::unique_ptr<geom::Geometry> empty;
225
226 UnionStrategy* unionFunction;
227 ClassicUnionStrategy defaultUnionFunction;
228
229};
230
231
232} // namespace geos::operation::union
233} // namespace geos::operation
234} // namespace geos
235
236#ifdef _MSC_VER
237#pragma warning(pop)
238#endif
239
Supplies a set of utility methods for building Geometry objects from CoordinateSequence or other Geom...
Definition GeometryFactory.h:65
std::unique_ptr< Geometry > createEmptyGeometry() const
Construct the EMPTY Geometry.
Basic implementation of Geometry, constructed and destructed by GeometryFactory.
Definition Geometry.h:186
const GeometryFactory * getFactory() const
Gets the factory which contains the context in which this geometry was created.
Definition Geometry.h:216
Unions a collection of Geometry or a single Geometry (which may be a collection) together.
Definition UnaryUnionOp.h:86
std::unique_ptr< geom::Geometry > Union()
Gets the union of the input geometries.
Definition UnionStrategy.h:40
Basic namespace for all GEOS functionalities.
Definition geos.h:39