GeographicLib 2.3

Planimeter.cpp
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1/**
2 * \file Planimeter.cpp
3 * \brief Command line utility for measuring the area of geodesic polygons
4 *
5 * Copyright (c) Charles Karney (2010-2023) <karney@alum.mit.edu> and licensed
6 * under the MIT/X11 License. For more information, see
7 * https://geographiclib.sourceforge.io/
8 *
9 * See the <a href="Planimeter.1.html">man page</a> for usage information.
10 **********************************************************************/
11
12#include <iostream>
13#include <string>
14#include <sstream>
15#include <fstream>
16#include <GeographicLib/PolygonArea.hpp>
17#include <GeographicLib/DMS.hpp>
18#include <GeographicLib/Utility.hpp>
19#include <GeographicLib/GeoCoords.hpp>
20#include <GeographicLib/AuxLatitude.hpp>
21
22#if defined(_MSC_VER)
23// Squelch warnings about constant conditional expressions
24# pragma warning (disable: 4127)
25#endif
26
27#include "Planimeter.usage"
28
29 int main(int argc, const char* const argv[]) {
30 try {
31 using namespace GeographicLib;
32 typedef Math::real real;
33 Utility::set_digits();
34 enum { GEODESIC, AUTHALIC, RHUMB };
35 real
36 a = Constants::WGS84_a(),
37 f = Constants::WGS84_f();
38 bool reverse = false, sign = true, polyline = false, longfirst = false,
39 exact = false, geoconvert_compat = false;
40 int linetype = GEODESIC;
41 int prec = 6;
42 std::string istring, ifile, ofile, cdelim;
43 char lsep = ';';
44
45 for (int m = 1; m < argc; ++m) {
46 std::string arg(argv[m]);
47 if (arg == "-r")
48 reverse = !reverse;
49 else if (arg == "-s")
50 sign = !sign;
51 else if (arg == "-l")
52 polyline = !polyline;
53 else if (arg == "-e") {
54 if (m + 2 >= argc) return usage(1, true);
55 try {
56 a = Utility::val<real>(std::string(argv[m + 1]));
57 f = Utility::fract<real>(std::string(argv[m + 2]));
58 }
59 catch (const std::exception& e) {
60 std::cerr << "Error decoding arguments of -e: " << e.what() << "\n";
61 return 1;
62 }
63 m += 2;
64 } else if (arg == "-w")
65 longfirst = !longfirst;
66 else if (arg == "-p") {
67 if (++m == argc) return usage(1, true);
68 try {
69 prec = Utility::val<int>(std::string(argv[m]));
70 }
71 catch (const std::exception&) {
72 std::cerr << "Precision " << argv[m] << " is not a number\n";
73 return 1;
74 }
75 } else if (arg == "-G")
76 linetype = GEODESIC;
77 else if (arg == "-Q")
78 linetype = AUTHALIC;
79 else if (arg == "-R")
80 linetype = RHUMB;
81 else if (arg == "-E")
82 exact = true;
83 else if (arg == "--geoconvert-input")
84 geoconvert_compat = true;
85 else if (arg == "--input-string") {
86 if (++m == argc) return usage(1, true);
87 istring = argv[m];
88 } else if (arg == "--input-file") {
89 if (++m == argc) return usage(1, true);
90 ifile = argv[m];
91 } else if (arg == "--output-file") {
92 if (++m == argc) return usage(1, true);
93 ofile = argv[m];
94 } else if (arg == "--line-separator") {
95 if (++m == argc) return usage(1, true);
96 if (std::string(argv[m]).size() != 1) {
97 std::cerr << "Line separator must be a single character\n";
98 return 1;
99 }
100 lsep = argv[m][0];
101 } else if (arg == "--comment-delimiter") {
102 if (++m == argc) return usage(1, true);
103 cdelim = argv[m];
104 } else if (arg == "--version") {
105 std::cout << argv[0] << ": GeographicLib version "
106 << GEOGRAPHICLIB_VERSION_STRING << "\n";
107 return 0;
108 } else
109 return usage(!(arg == "-h" || arg == "--help"), arg != "--help");
110 }
111
112 if (!ifile.empty() && !istring.empty()) {
113 std::cerr << "Cannot specify --input-string and --input-file together\n";
114 return 1;
115 }
116 if (ifile == "-") ifile.clear();
117 std::ifstream infile;
118 std::istringstream instring;
119 if (!ifile.empty()) {
120 infile.open(ifile.c_str());
121 if (!infile.is_open()) {
122 std::cerr << "Cannot open " << ifile << " for reading\n";
123 return 1;
124 }
125 } else if (!istring.empty()) {
126 std::string::size_type m = 0;
127 while (true) {
128 m = istring.find(lsep, m);
129 if (m == std::string::npos)
130 break;
131 istring[m] = '\n';
132 }
133 instring.str(istring);
134 }
135 std::istream* input = !ifile.empty() ? &infile :
136 (!istring.empty() ? &instring : &std::cin);
137
138 std::ofstream outfile;
139 if (ofile == "-") ofile.clear();
140 if (!ofile.empty()) {
141 outfile.open(ofile.c_str());
142 if (!outfile.is_open()) {
143 std::cerr << "Cannot open " << ofile << " for writing\n";
144 return 1;
145 }
146 }
147 std::ostream* output = !ofile.empty() ? &outfile : &std::cout;
148
149 // Linetype is one of GEODESIC, AUTHALIC, RHUMB
150 const AuxLatitude ellip(a, f);
151 if (linetype == AUTHALIC) {
152 // adjusting a and f to correspond to the authalic sphere
153 using std::sqrt;
154 a = sqrt(ellip.AuthalicRadiusSquared(exact));
155 f = 0;
156 }
157 const Geodesic geod(a, linetype != RHUMB ? f : 0,
158 exact && linetype != RHUMB);
159 const Rhumb rhumb(a, linetype == RHUMB ? f : 0,
160 exact && linetype == RHUMB);
161 PolygonArea poly(geod, polyline);
162 PolygonAreaRhumb polyr(rhumb, polyline);
163 GeoCoords p;
164
165 // Max precision = 10: 0.1 nm in distance, 10^-15 deg (= 0.11 nm),
166 // 10^-11 sec (= 0.3 nm).
167 prec = std::min(10 + Math::extra_digits(), std::max(0, prec));
168 std::string s, eol("\n");
169 real perimeter, area;
170 unsigned num;
171 std::istringstream str;
172 std::string slat, slon, junk;
173 real lat = 0, lon = 0;
174 while (std::getline(*input, s)) {
175 if (!cdelim.empty()) {
176 std::string::size_type m = s.find(cdelim);
177 if (m != std::string::npos) {
178 eol = " " + s.substr(m) + "\n";
179 s = s.substr(0, m);
180 }
181 }
182 bool endpoly = s.empty();
183 if (!endpoly) {
184 try {
185 using std::isnan;
186 if (geoconvert_compat) {
187 p.Reset(s, true, longfirst);
188 lat = p.Latitude(); lon = p.Longitude();
189 } else {
190 str.clear(); str.str(s);
191 if (!(str >> slat >> slon))
192 throw GeographicErr("incomplete input");
193 if (str >> junk)
194 throw GeographicErr("extra input");
195 DMS::DecodeLatLon(slat, slon, lat, lon, longfirst);
196 }
197 if (isnan(lat) || isnan(lon))
198 endpoly = true;
199 }
200 catch (const GeographicErr&) {
201 endpoly = true;
202 }
203 }
204 if (endpoly) {
205 num =
206 linetype == RHUMB ? polyr.Compute(reverse, sign, perimeter, area) :
207 poly.Compute(reverse, sign, perimeter, area); // geodesic + authalic
208 if (num > 0) {
209 *output << num << " " << Utility::str(perimeter, prec);
210 if (!polyline) {
211 *output << " " << Utility::str(area, std::max(0, prec - 5));
212 }
213 *output << eol;
214 }
215 linetype == RHUMB ? polyr.Clear() : poly.Clear();
216 eol = "\n";
217 } else {
218 linetype == RHUMB ? polyr.AddPoint(lat, lon) :
219 poly.AddPoint
220 (linetype == AUTHALIC ?
221 ellip.Convert(AuxLatitude::PHI, AuxLatitude::XI, lat, exact) : lat,
222 lon);
223 }
224 }
225 num =
226 linetype == RHUMB ? polyr.Compute(reverse, sign, perimeter, area) :
227 poly.Compute(reverse, sign, perimeter, area);
228 if (num > 0) {
229 *output << num << " " << Utility::str(perimeter, prec);
230 if (!polyline) {
231 *output << " " << Utility::str(area, std::max(0, prec - 5));
232 }
233 *output << eol;
234 }
235 linetype == RHUMB ? polyr.Clear() : poly.Clear();
236 eol = "\n";
237 return 0;
238 }
239 catch (const std::exception& e) {
240 std::cerr << "Caught exception: " << e.what() << "\n";
241 return 1;
242 }
243 catch (...) {
244 std::cerr << "Caught unknown exception\n";
245 return 1;
246 }
247}
AuxLatitude.hpp
Header for the GeographicLib::AuxLatitude class.
DMS.hpp
Header for GeographicLib::DMS class.
GeoCoords.hpp
Header for GeographicLib::GeoCoords class.
real
GeographicLib::Math::real real
Definition: GeodSolve.cpp:29
main
int main(int argc, const char *const argv[])
Definition: Planimeter.cpp:29
PolygonArea.hpp
Header for GeographicLib::PolygonAreaT class.
Utility.hpp
Header for GeographicLib::Utility class.
GeographicLib::AuxLatitude
Conversions between auxiliary latitudes.
Definition: AuxLatitude.hpp:75
GeographicLib::AuxLatitude::Convert
AuxAngle Convert(int auxin, int auxout, const AuxAngle &zeta, bool exact=false) const
Definition: AuxLatitude.cpp:304
GeographicLib::AuxLatitude::AuthalicRadiusSquared
Math::real AuthalicRadiusSquared(bool exact=false) const
Definition: AuxLatitude.cpp:359
GeographicLib::GeoCoords
Conversion between geographic coordinates.
Definition: GeoCoords.hpp:49
GeographicLib::GeoCoords::Reset
void Reset(const std::string &s, bool centerp=true, bool longfirst=false)
Definition: GeoCoords.cpp:19
GeographicLib::GeoCoords::Latitude
Math::real Latitude() const
Definition: GeoCoords.hpp:276
GeographicLib::GeoCoords::Longitude
Math::real Longitude() const
Definition: GeoCoords.hpp:281
GeographicLib::Geodesic
Geodesic calculations
Definition: Geodesic.hpp:175
GeographicLib::GeographicErr
Exception handling for GeographicLib.
Definition: Constants.hpp:316
GeographicLib::Math::real
double real
Definition: Math.hpp:100
GeographicLib::PolygonAreaT::PolygonAreaRhumb
PolygonAreaT< Rhumb > PolygonAreaRhumb
Definition: PolygonArea.hpp:309
GeographicLib::PolygonAreaT::PolygonArea
PolygonAreaT< Geodesic > PolygonArea
Definition: PolygonArea.hpp:294
GeographicLib::Rhumb
Solve of the direct and inverse rhumb problems.
Definition: Rhumb.hpp:79
GeographicLib
Namespace for GeographicLib.
Definition: Accumulator.cpp:12