GEOS  3.14.0dev
OffsetSegmentGenerator.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/buffer/OffsetSegmentGenerator.java r378 (JTS-1.12)
16  *
17  **********************************************************************/
18 
19 #pragma once
20 
21 #include <geos/export.h>
22 
23 #include <vector>
24 
25 #include <geos/algorithm/LineIntersector.h> // for composition
26 #include <geos/geom/Coordinate.h> // for composition
27 #include <geos/geom/LineSegment.h> // for composition
28 #include <geos/operation/buffer/BufferParameters.h> // for composition
29 #include <geos/operation/buffer/OffsetSegmentString.h> // for composition
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 
60 class GEOS_DLL OffsetSegmentGenerator {
61 
62 public:
63 
64  /*
65  * @param nBufParams buffer parameters, this object will
66  * keep a reference to the passed parameters
67  * so caller must make sure the object is
68  * kept alive for the whole lifetime of
69  * the buffer builder.
70  */
71  OffsetSegmentGenerator(const geom::PrecisionModel* newPrecisionModel,
72  const BufferParameters& bufParams, double distance);
73 
86  bool
88  {
89  return _hasNarrowConcaveAngle;
90  }
91 
92  void initSideSegments(const geom::Coordinate& nS1,
93  const geom::Coordinate& nS2, int nSide);
94 
103  void
104  getCoordinates(std::vector<geom::CoordinateSequence*>& to)
105  {
106  to.push_back(segList.getCoordinates());
107  }
108 
109  std::unique_ptr<geom::CoordinateSequence>
110  getCoordinates()
111  {
112  return std::unique_ptr<geom::CoordinateSequence>(segList.getCoordinates());
113  }
114 
115  void
116  closeRing()
117  {
118  segList.closeRing();
119  }
120 
122  void createCircle(const geom::Coordinate& p, double distance);
123 
125  void createSquare(const geom::Coordinate& p, double distance);
126 
128  void
130  {
131  segList.addPt(offset1.p0);
132  }
133 
135  void
137  {
138  segList.addPt(offset1.p1);
139  }
140 
141  void addNextSegment(const geom::Coordinate& p, bool addStartPoint);
142 
147  const geom::Coordinate& p1);
148 
149  void
150  addSegments(const geom::CoordinateSequence& pts, bool isForward)
151  {
152  segList.addPts(pts, isForward);
153  }
154 
167  static void computeOffsetSegment(const geom::LineSegment& seg,
168  int side, double distance,
169  geom::LineSegment& offset);
170 
171 private:
172 
177  static const double OFFSET_SEGMENT_SEPARATION_FACTOR; // 1.0E-3;
178 
183  static const double INSIDE_TURN_VERTEX_SNAP_DISTANCE_FACTOR; // 1.0E-3;
184 
188  static const double CURVE_VERTEX_SNAP_DISTANCE_FACTOR; // 1.0E-6;
189 
193  static const int MAX_CLOSING_SEG_LEN_FACTOR = 80;
194 
199  double maxCurveSegmentError; // 0.0
200 
205  double filletAngleQuantum;
206 
224  int closingSegLengthFactor; // 1;
225 
234  OffsetSegmentString segList;
235 
236  double distance;
237 
238  const geom::PrecisionModel* precisionModel;
239 
240  const BufferParameters& bufParams;
241 
243 
244  geom::Coordinate s0, s1, s2;
245 
246  geom::LineSegment seg0;
247 
248  geom::LineSegment seg1;
249 
250  geom::LineSegment offset0;
251 
252  geom::LineSegment offset1;
253 
254  int side;
255 
256  bool _hasNarrowConcaveAngle; // =false
257 
258  void addCollinear(bool addStartPoint);
259 
266  void addMitreJoin(const geom::Coordinate& cornerPt,
267  const geom::LineSegment& offset0,
268  const geom::LineSegment& offset1,
269  double distance);
270 
271 
282  void addLimitedMitreJoin(
283  const geom::LineSegment& offset0,
284  const geom::LineSegment& offset1,
285  double distance,
286  double mitreLimitDistance);
287 
295  static geom::LineSegment extend(const geom::LineSegment& seg, double dist);
296 
307  static geom::Coordinate project(const geom::Coordinate& pt, double d, double dir);
308 
316  void addBevelJoin(const geom::LineSegment& offset0,
317  const geom::LineSegment& offset1);
318 
319  static const double PI; // 3.14159265358979
320 
321  // Not in JTS, used for single-sided buffers
322  int endCapIndex;
323 
324  void init(double newDistance);
325 
333  static const double SIMPLIFY_FACTOR; // 100.0;
334 
340  void addOutsideTurn(int orientation, bool addStartPoint);
341 
347  void addInsideTurn(int orientation, bool addStartPoint);
348 
360  void addDirectedFillet(const geom::Coordinate& p, const geom::Coordinate& p0,
361  const geom::Coordinate& p1,
362  int direction, double radius);
363 
373  void addDirectedFillet(const geom::Coordinate& p, double startAngle,
374  double endAngle, int direction, double radius);
375 private:
376  // An OffsetSegmentGenerator cannot be copied because of member "const BufferParameters& bufParams"
377  // Not declaring these functions triggers MSVC warning C4512: "assignment operator could not be generated"
379  void operator=(const OffsetSegmentGenerator&);
380 
381 };
382 
383 } // namespace geos::operation::buffer
384 } // namespace geos::operation
385 } // namespace geos
386 
387 #ifdef _MSC_VER
388 #pragma warning(pop)
389 #endif
390 
A LineIntersector is an algorithm that can both test whether two line segments intersect and compute ...
Definition: LineIntersector.h:53
The internal representation of a list of coordinates inside a Geometry.
Definition: CoordinateSequence.h:56
Coordinate is the lightweight class used to store coordinates.
Definition: Coordinate.h:217
Definition: LineSegment.h:61
Specifies the precision model of the Coordinate in a Geometry.
Definition: PrecisionModel.h:88
Contains the parameters which describe how a buffer should be constructed.
Definition: BufferParameters.h:56
Definition: OffsetSegmentGenerator.h:60
void addFirstSegment()
Add first offset point.
Definition: OffsetSegmentGenerator.h:129
bool hasNarrowConcaveAngle() const
Definition: OffsetSegmentGenerator.h:87
void addLastSegment()
Add last offset point.
Definition: OffsetSegmentGenerator.h:136
static void computeOffsetSegment(const geom::LineSegment &seg, int side, double distance, geom::LineSegment &offset)
Compute an offset segment for an input segment on a given side and at a given distance.
void addLineEndCap(const geom::Coordinate &p0, const geom::Coordinate &p1)
Add an end cap around point p1, terminating a line segment coming from p0.
void createSquare(const geom::Coordinate &p, double distance)
Adds a CW square around a point.
void createCircle(const geom::Coordinate &p, double distance)
Adds a CW circle around a point.
void getCoordinates(std::vector< geom::CoordinateSequence * > &to)
Definition: OffsetSegmentGenerator.h:104
Definition: OffsetSegmentString.h:41
Basic namespace for all GEOS functionalities.
Definition: Angle.h:25