GEOS  3.8.0dev
OffsetCurveBuilder.h
1 /**********************************************************************
2  *
3  * GEOS - Geometry Engine Open Source
4  * http://geos.osgeo.org
5  *
6  * Copyright (C) 2009-2011 Sandro Santilli <strk@kbt.io>
7  * Copyright (C) 2006-2007 Refractions Research Inc.
8  *
9  * This is free software; you can redistribute and/or modify it under
10  * the terms of the GNU Lesser General Public Licence as published
11  * by the Free Software Foundation.
12  * See the COPYING file for more information.
13  *
14  **********************************************************************
15  *
16  * Last port: operation/buffer/OffsetCurveBuilder.java r378 (JTS-1.12)
17  *
18  **********************************************************************/
19 
20 #ifndef GEOS_OP_BUFFER_OFFSETCURVEBUILDER_H
21 #define GEOS_OP_BUFFER_OFFSETCURVEBUILDER_H
22 
23 #include <geos/export.h>
24 
25 #include <geos/operation/buffer/BufferParameters.h> // for composition
26 #include <geos/operation/buffer/OffsetSegmentGenerator.h>
27 
28 #include <vector>
29 #include <memory> // for unique_ptr
30 
31 #ifdef _MSC_VER
32 #pragma warning(push)
33 #pragma warning(disable: 4251) // warning C4251: needs to have dll-interface to be used by clients of class
34 #endif
35 
36 // Forward declarations
37 namespace geos {
38 namespace geom {
39 class CoordinateSequence;
40 class PrecisionModel;
41 }
42 }
43 
44 namespace geos {
45 namespace operation { // geos.operation
46 namespace buffer { // geos.operation.buffer
47 
62 class GEOS_DLL OffsetCurveBuilder {
63 public:
64 
65  /*
66  * @param nBufParams buffer parameters, this object will
67  * keep a reference to the passed parameters
68  * so caller must make sure the object is
69  * kept alive for the whole lifetime of
70  * the buffer builder.
71  */
72  OffsetCurveBuilder(const geom::PrecisionModel* newPrecisionModel,
73  const BufferParameters& nBufParams)
74  :
75  distance(0.0),
76  precisionModel(newPrecisionModel),
77  bufParams(nBufParams)
78  {}
79 
85  const BufferParameters&
87  {
88  return bufParams;
89  }
90 
100  void getLineCurve(const geom::CoordinateSequence* inputPts,
101  double distance,
102  std::vector<geom::CoordinateSequence*>& lineList);
103 
120  void getSingleSidedLineCurve(const geom::CoordinateSequence* inputPts,
121  double distance, std::vector<geom::CoordinateSequence*>& lineList,
122  bool leftSide, bool rightSide) ;
123 
131  void getRingCurve(const geom::CoordinateSequence* inputPts, int side,
132  double distance,
133  std::vector<geom::CoordinateSequence*>& lineList);
134 
135 
136 private:
137 
138  double distance;
139 
140  const geom::PrecisionModel* precisionModel;
141 
142  const BufferParameters& bufParams;
143 
151  static const double SIMPLIFY_FACTOR; // 100.0;
152 
160  double simplifyTolerance(double bufDistance);
161 
162  void computeLineBufferCurve(const geom::CoordinateSequence& inputPts,
163  OffsetSegmentGenerator& segGen);
164 
165  void computeSingleSidedBufferCurve(const geom::CoordinateSequence& inputPts,
166  bool isRightSide,
167  OffsetSegmentGenerator& segGen);
168 
169  void computeRingBufferCurve(const geom::CoordinateSequence& inputPts,
170  int side, OffsetSegmentGenerator& segGen);
171 
172  std::unique_ptr<OffsetSegmentGenerator> getSegGen(double dist);
173 
174  void computePointCurve(const geom::Coordinate& pt,
175  OffsetSegmentGenerator& segGen);
176 
177 
178  // Declare type as noncopyable
179  OffsetCurveBuilder(const OffsetCurveBuilder& other) = delete;
180  OffsetCurveBuilder& operator=(const OffsetCurveBuilder& rhs) = delete;
181 };
182 
183 } // namespace geos::operation::buffer
184 } // namespace geos::operation
185 } // namespace geos
186 
187 #ifdef _MSC_VER
188 #pragma warning(pop)
189 #endif
190 
191 #endif // ndef GEOS_OP_BUFFER_OFFSETCURVEBUILDER_H
192 
Definition: OffsetSegmentGenerator.h:61
Coordinate is the lightweight class used to store coordinates.
Definition: Coordinate.h:60
Specifies the precision model of the Coordinate in a Geometry.
Definition: PrecisionModel.h:87
Computes the raw offset curve for a single Geometry component (ring, line or point).
Definition: OffsetCurveBuilder.h:62
const BufferParameters & getBufferParameters() const
Definition: OffsetCurveBuilder.h:86
Basic namespace for all GEOS functionalities.
Definition: IndexedNestedRingTester.h:25
Contains the parameters which describe how a buffer should be constructed.
Definition: BufferParameters.h:57
The internal representation of a list of coordinates inside a Geometry.
Definition: CoordinateSequence.h:58