GEOS: LineIntersector.h Source File

GEOS 3.5.0

- Main Page
- Related Pages
- Namespaces
- Classes
- Files

- File List

LineIntersector.h
1 /**********************************************************************
2 *
3 * GEOS - Geometry Engine Open Source
4 * http://geos.osgeo.org
5 *
6 * Copyright (C) 2005-2006 Refractions Research Inc.
7 * Copyright (C) 2001-2002 Vivid Solutions 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: algorithm/RobustLineIntersector.java r785 (JTS-1.13+)
17 *
18 **********************************************************************/
19
20 #ifndef GEOS_ALGORITHM_LINEINTERSECTOR_H
21 #define GEOS_ALGORITHM_LINEINTERSECTOR_H
22
23 #include <geos/export.h>
24 #include <string>
25
26 #include <geos/geom/Coordinate.h>
27
28 // Forward declarations
29 namespace geos {
30 namespace geom {
31 class PrecisionModel;
32 }
33 }
34
35 namespace geos {
36 namespace algorithm { // geos::algorithm
37
49 class GEOS_DLL LineIntersector {
50 public:
51
55 static double interpolateZ(const geom::Coordinate &p, const geom::Coordinate &p0, const geom::Coordinate &p1);
56
57
59 //
76 static double computeEdgeDistance(const geom::Coordinate& p, const geom::Coordinate& p0, const geom::Coordinate& p1);
77
78 static double nonRobustComputeEdgeDistance(const geom::Coordinate& p,const geom::Coordinate& p1,const geom::Coordinate& p2);
79
80 LineIntersector(const geom::PrecisionModel* initialPrecisionModel=NULL)
81 :
82 precisionModel(initialPrecisionModel),
83 result(0),
84 isProperVar(false)
85 {}
86
87 ~LineIntersector() {}
88
96 bool isInteriorIntersection();
97
105 bool isInteriorIntersection(int inputLineIndex);
106
108 //
113 void setPrecisionModel(const geom::PrecisionModel *newPM) {
114 precisionModel=newPM;
115 }
116
118 //
123 void computeIntersection(const geom::Coordinate& p, const geom::Coordinate& p1, const geom::Coordinate& p2);
124
126 static bool hasIntersection(const geom::Coordinate& p,const geom::Coordinate& p1,const geom::Coordinate& p2);
127
128 // These are deprecated, due to ambiguous naming
129 enum {
130 DONT_INTERSECT=0,
131 DO_INTERSECT=1,
132 COLLINEAR=2
133 };
134
135 enum {
137 NO_INTERSECTION=0,
138
140 POINT_INTERSECTION=1,
141
143 COLLINEAR_INTERSECTION=2
144 };
145
147 void computeIntersection(const geom::Coordinate& p1, const geom::Coordinate& p2,
148 const geom::Coordinate& p3, const geom::Coordinate& p4);
149
150 std::string toString() const;
151
157 bool hasIntersection() const { return result!=NO_INTERSECTION; }
158
160 //
163 int getIntersectionNum() const { return result; }
164
165
167 //
172 const geom::Coordinate& getIntersection(int intIndex) const {
173 return intPt[intIndex];
174 }
175
177 //
180 static bool isSameSignAndNonZero(double a,double b);
181
192 bool isIntersection(const geom::Coordinate& pt) const;
193
208 bool isProper() const {
209 return hasIntersection()&&isProperVar;
210 }
211
222 const geom::Coordinate& getIntersectionAlongSegment(int segmentIndex,int intIndex);
223
233 int getIndexAlongSegment(int segmentIndex,int intIndex);
234
244 double getEdgeDistance(int geomIndex,int intIndex) const;
245
246 private:
247
248 void intersectionWithNormalization(const geom::Coordinate& p1,
249 const geom::Coordinate& p2,
250 const geom::Coordinate& q1,
251 const geom::Coordinate& q2,
252 geom::Coordinate &ret) const;
253
258 const geom::PrecisionModel *precisionModel;
259
260 int result;
261
262 const geom::Coordinate *inputLines[2][2];
263
268 geom::Coordinate intPt[2];
269
274 int intLineIndex[2][2];
275
276 bool isProperVar;
277 //Coordinate &pa;
278 //Coordinate &pb;
279
280 bool isCollinear() const { return result==COLLINEAR_INTERSECTION; }
281
282 int computeIntersect(const geom::Coordinate& p1,const geom::Coordinate& p2,const geom::Coordinate& q1,const geom::Coordinate& q2);
283
284 bool isEndPoint() const {
285 return hasIntersection()&&!isProperVar;
286 }
287
288 void computeIntLineIndex();
289
290 void computeIntLineIndex(int segmentIndex);
291
292 int computeCollinearIntersection(const geom::Coordinate& p1,
293 const geom::Coordinate& p2, const geom::Coordinate& q1,
294 const geom::Coordinate& q2);
295
305 void intersection(const geom::Coordinate& p1,
306 const geom::Coordinate& p2,
307 const geom::Coordinate& q1,
308 const geom::Coordinate& q2,
309 geom::Coordinate &ret) const;
310
311 double smallestInAbsValue(double x1, double x2,
312 double x3, double x4) const;
313
324 bool isInSegmentEnvelopes(const geom::Coordinate& intPt) const;
325
337 void normalizeToEnvCentre(geom::Coordinate &n00, geom::Coordinate &n01,
338 geom::Coordinate &n10, geom::Coordinate &n11,
339 geom::Coordinate &normPt) const;
340
353 void safeHCoordinateIntersection(const geom::Coordinate& p1,
354 const geom::Coordinate& p2,
355 const geom::Coordinate& q1,
356 const geom::Coordinate& q2,
357 geom::Coordinate& intPt) const;
358
359 };
360
361 } // namespace geos::algorithm
362 } // namespace geos
363
364
365 #endif // GEOS_ALGORITHM_LINEINTERSECTOR_H
366
geos::geom::Coordinate
Coordinate is the lightweight class used to store coordinates.
Definition: Coordinate.h:60
geos::algorithm::LineIntersector::getIntersectionNum
int getIntersectionNum() const
Returns the number of intersection points found.
Definition: LineIntersector.h:163
geos::geom::PrecisionModel
Specifies the precision model of the Coordinate in a Geometry.
Definition: PrecisionModel.h:87
geos::algorithm::LineIntersector::getIntersection
const geom::Coordinate & getIntersection(int intIndex) const
Returns the intIndex&#39;th intersection point.
Definition: LineIntersector.h:172
geos::algorithm::LineIntersector::isProper
bool isProper() const
Tests whether an intersection is proper.
Definition: LineIntersector.h:208
geos::algorithm::LineIntersector
A LineIntersector is an algorithm that can both test whether two line segments intersect and compute ...
Definition: LineIntersector.h:49
geos
Basic namespace for all GEOS functionalities.
Definition: IndexedNestedRingTester.h:25
geos::algorithm::LineIntersector::setPrecisionModel
void setPrecisionModel(const geom::PrecisionModel *newPM)
Force computed intersection to be rounded to a given precision model.
Definition: LineIntersector.h:113
geos::algorithm::LineIntersector::hasIntersection
bool hasIntersection() const
Definition: LineIntersector.h:157