This file is indexed.

/usr/share/doc/geographiclib/html/OSGB_8cpp_source.html is in geographiclib-tools 1.8-2.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/>
<title>GeographicLib: OSGB.cpp Source File</title>
<link href="tabs.css" rel="stylesheet" type="text/css"/>
<link href="doxygen.css" rel="stylesheet" type="text/css"/>
</head>
<body>
<!-- Generated by Doxygen 1.7.1 -->
<div class="navigation" id="top">
  <div class="tabs">
    <ul class="tablist">
      <li><a href="index.html"><span>Main&nbsp;Page</span></a></li>
      <li><a href="pages.html"><span>Related&nbsp;Pages</span></a></li>
      <li><a href="namespaces.html"><span>Namespaces</span></a></li>
      <li><a href="annotated.html"><span>Classes</span></a></li>
      <li class="current"><a href="files.html"><span>Files</span></a></li>
      <li><a href="dirs.html"><span>Directories</span></a></li>
    </ul>
  </div>
  <div class="tabs2">
    <ul class="tablist">
      <li><a href="files.html"><span>File&nbsp;List</span></a></li>
      <li><a href="globals.html"><span>File&nbsp;Members</span></a></li>
    </ul>
  </div>
  <div class="navpath">
    <ul>
      <li><a class="el" href="dir_b6dff8fdfd5d70bd61ba562840823df9.html">src</a>      </li>
    </ul>
  </div>
</div>
<div class="header">
  <div class="headertitle">
<h1>OSGB.cpp</h1>  </div>
</div>
<div class="contents">
<a href="OSGB_8cpp.html">Go to the documentation of this file.</a><div class="fragment"><pre class="fragment"><a name="l00001"></a>00001 <span class="comment">/**</span>
<a name="l00002"></a>00002 <span class="comment"> * \file OSGB.cpp</span>
<a name="l00003"></a>00003 <span class="comment"> * \brief Implementation for GeographicLib::OSGB class</span>
<a name="l00004"></a>00004 <span class="comment"> *</span>
<a name="l00005"></a>00005 <span class="comment"> * Copyright (c) Charles Karney (2010, 2011) &lt;charles@karney.com&gt; and licensed</span>
<a name="l00006"></a>00006 <span class="comment"> * under the LGPL.  For more information, see</span>
<a name="l00007"></a>00007 <span class="comment"> * http://geographiclib.sourceforge.net/</span>
<a name="l00008"></a>00008 <span class="comment"> **********************************************************************/</span>
<a name="l00009"></a>00009 
<a name="l00010"></a>00010 <span class="preprocessor">#include &quot;<a class="code" href="OSGB_8hpp.html" title="Header for GeographicLib::OSGB class.">GeographicLib/OSGB.hpp</a>&quot;</span>
<a name="l00011"></a>00011 
<a name="l00012"></a><a class="code" href="OSGB_8cpp.html#af7fa9aa83a3be95cccc572fc3b399b58">00012</a> <span class="preprocessor">#define GEOGRAPHICLIB_OSGB_CPP &quot;$Id: OSGB.cpp 6954 2011-02-16 14:36:56Z karney $&quot;</span>
<a name="l00013"></a>00013 <span class="preprocessor"></span>
<a name="l00014"></a>00014 <a class="code" href="Constants_8hpp.html#af90fa899707a2ac513d5e4c76853bbf5">RCSID_DECL</a>(<a class="code" href="OSGB_8cpp.html#af7fa9aa83a3be95cccc572fc3b399b58">GEOGRAPHICLIB_OSGB_CPP</a>)
<a name="l00015"></a>00015 <a class="code" href="Constants_8hpp.html#af90fa899707a2ac513d5e4c76853bbf5">RCSID_DECL</a>(<a class="code" href="OSGB_8hpp.html#a786c5942146679103feb716bea66a0a7">GEOGRAPHICLIB_OSGB_HPP</a>)
<a name="l00016"></a>00016 
<a name="l00017"></a>00017 namespace GeographicLib {
<a name="l00018"></a>00018 
<a name="l00019"></a>00019   <span class="keyword">using namespace </span>std;
<a name="l00020"></a>00020 
<a name="l00021"></a>00021   <span class="keyword">const</span> <span class="keywordtype">string</span> OSGB::letters = <span class="stringliteral">&quot;ABCDEFGHJKLMNOPQRSTUVWXYZ&quot;</span>;
<a name="l00022"></a>00022   <span class="keyword">const</span> <span class="keywordtype">string</span> OSGB::digits = <span class="stringliteral">&quot;0123456789&quot;</span>;
<a name="l00023"></a>00023 
<a name="l00024"></a>00024   <span class="keyword">const</span> TransverseMercator
<a name="l00025"></a>00025   OSGB::OSGBTM(MajorRadius(), InverseFlattening(), CentralScale());
<a name="l00026"></a>00026 
<a name="l00027"></a>00027   <a class="code" href="Geod_8cpp.html#a5caf95d46b184d9ca1d3764b3781b3c9">Math::real</a> OSGB::computenorthoffset() <span class="keywordflow">throw</span>() {
<a name="l00028"></a>00028     <a class="code" href="Geod_8cpp.html#a5caf95d46b184d9ca1d3764b3781b3c9">real</a> x, y;
<a name="l00029"></a>00029     OSGBTM.Forward(<a class="code" href="Geod_8cpp.html#a5caf95d46b184d9ca1d3764b3781b3c9">real</a>(0), OriginLatitude(), <a class="code" href="Geod_8cpp.html#a5caf95d46b184d9ca1d3764b3781b3c9">real</a>(0), x, y);
<a name="l00030"></a>00030     <span class="keywordflow">return</span> FalseNorthing() - y;
<a name="l00031"></a>00031   }
<a name="l00032"></a>00032 
<a name="l00033"></a>00033   <span class="keyword">const</span> <a class="code" href="Geod_8cpp.html#a5caf95d46b184d9ca1d3764b3781b3c9">Math::real</a> OSGB::northoffset = computenorthoffset();
<a name="l00034"></a>00034 
<a name="l00035"></a><a class="code" href="classGeographicLib_1_1OSGB.html#a0a79e8f2babae1eb0305a0e728fea8c8">00035</a>   <span class="keywordtype">void</span> OSGB::GridReference(real x, real y, <span class="keywordtype">int</span> prec, std::string&amp; gridref) {
<a name="l00036"></a>00036     CheckCoords(x, y);
<a name="l00037"></a>00037     <span class="keywordflow">if</span> (!(prec &gt;= 0 || prec &lt;= maxprec))
<a name="l00038"></a>00038       <span class="keywordflow">throw</span> <a class="code" href="classGeographicLib_1_1GeographicErr.html" title="Exception handling for GeographicLib">GeographicErr</a>(<span class="stringliteral">&quot;OSGB precision &quot;</span> + str(prec) + <span class="stringliteral">&quot; not in [0, &quot;</span>
<a name="l00039"></a>00039                           + str(<span class="keywordtype">int</span>(maxprec)) + <span class="stringliteral">&quot;]&quot;</span>);
<a name="l00040"></a>00040     <span class="keywordtype">char</span> grid[2 + 2 * maxprec];
<a name="l00041"></a>00041     <span class="keywordtype">int</span>
<a name="l00042"></a>00042       xh = int(floor(x)) / tile,
<a name="l00043"></a>00043       yh = int(floor(y)) / tile;
<a name="l00044"></a>00044     real
<a name="l00045"></a>00045       xf = x - tile * xh,
<a name="l00046"></a>00046       yf = y - tile * yh;
<a name="l00047"></a>00047     xh += tileoffx;
<a name="l00048"></a>00048     yh += tileoffy;
<a name="l00049"></a>00049     <span class="keywordtype">int</span> z = 0;
<a name="l00050"></a>00050     grid[z++] = letters[(tilegrid - (yh / tilegrid) - 1)
<a name="l00051"></a>00051                         * tilegrid + (xh / tilegrid)];
<a name="l00052"></a>00052     grid[z++] = letters[(tilegrid - (yh % tilegrid) - 1)
<a name="l00053"></a>00053                         * tilegrid + (xh % tilegrid)];
<a name="l00054"></a>00054     real mult = pow(<a class="code" href="Geod_8cpp.html#a5caf95d46b184d9ca1d3764b3781b3c9">real</a>(base), max(tilelevel - prec, 0));
<a name="l00055"></a>00055     <span class="keywordtype">int</span>
<a name="l00056"></a>00056       ix = int(floor(xf / mult)),
<a name="l00057"></a>00057       iy = int(floor(yf / mult));
<a name="l00058"></a>00058     <span class="keywordflow">for</span> (<span class="keywordtype">int</span> c = min(prec, <span class="keywordtype">int</span>(tilelevel)); c--;) {
<a name="l00059"></a>00059       grid[z + c] = digits[ ix % base ];
<a name="l00060"></a>00060       ix /= base;
<a name="l00061"></a>00061       grid[z + c + prec] = digits[ iy % base ];
<a name="l00062"></a>00062       iy /= base;
<a name="l00063"></a>00063     }
<a name="l00064"></a>00064     <span class="keywordflow">if</span> (prec &gt; tilelevel) {
<a name="l00065"></a>00065       xf -= floor(xf / mult);
<a name="l00066"></a>00066       yf -= floor(yf / mult);
<a name="l00067"></a>00067       mult = pow(<a class="code" href="Geod_8cpp.html#a5caf95d46b184d9ca1d3764b3781b3c9">real</a>(base), prec - tilelevel);
<a name="l00068"></a>00068       ix = int(floor(xf * mult));
<a name="l00069"></a>00069       iy = int(floor(yf * mult));
<a name="l00070"></a>00070       <span class="keywordflow">for</span> (<span class="keywordtype">int</span> c = prec - tilelevel; c--;) {
<a name="l00071"></a>00071         grid[z + c + tilelevel] = digits[ ix % base ];
<a name="l00072"></a>00072         ix /= base;
<a name="l00073"></a>00073         grid[z + c + tilelevel + prec] = digits[ iy % base ];
<a name="l00074"></a>00074         iy /= base;
<a name="l00075"></a>00075       }
<a name="l00076"></a>00076     }
<a name="l00077"></a>00077     <span class="keywordtype">int</span> mlen = z + 2 * prec;
<a name="l00078"></a>00078     gridref.resize(mlen);
<a name="l00079"></a>00079     copy(grid, grid + mlen, gridref.begin());
<a name="l00080"></a>00080   }
<a name="l00081"></a>00081 
<a name="l00082"></a><a class="code" href="classGeographicLib_1_1OSGB.html#a3693cfef49442747750e8393c81014aa">00082</a>   <span class="keywordtype">void</span> <a class="code" href="classGeographicLib_1_1OSGB.html#a0a79e8f2babae1eb0305a0e728fea8c8">OSGB::GridReference</a>(<span class="keyword">const</span> std::string&amp; gridref,
<a name="l00083"></a>00083                            real&amp; x, real&amp; y, <span class="keywordtype">int</span>&amp; prec,
<a name="l00084"></a>00084                            <span class="keywordtype">bool</span> centerp) {
<a name="l00085"></a>00085     <span class="keywordtype">int</span>
<a name="l00086"></a>00086       len = int(gridref.size()),
<a name="l00087"></a>00087       p = 0;
<a name="l00088"></a>00088     <span class="keywordtype">char</span> grid[2 + 2 * maxprec];
<a name="l00089"></a>00089     <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = 0; i &lt; len; ++i) {
<a name="l00090"></a>00090       <span class="keywordflow">if</span> (!isspace(gridref[i])) {
<a name="l00091"></a>00091         <span class="keywordflow">if</span> (p &gt;= 2 + 2 * maxprec)
<a name="l00092"></a>00092           <span class="keywordflow">throw</span> <a class="code" href="classGeographicLib_1_1GeographicErr.html" title="Exception handling for GeographicLib">GeographicErr</a>(<span class="stringliteral">&quot;OSGB string &quot;</span> + gridref + <span class="stringliteral">&quot; too long&quot;</span>);
<a name="l00093"></a>00093         grid[p++] = gridref[i];
<a name="l00094"></a>00094       }
<a name="l00095"></a>00095     }
<a name="l00096"></a>00096     len = p;
<a name="l00097"></a>00097     p = 0;
<a name="l00098"></a>00098     <span class="keywordflow">if</span> (len &lt; 2)
<a name="l00099"></a>00099       <span class="keywordflow">throw</span> <a class="code" href="classGeographicLib_1_1GeographicErr.html" title="Exception handling for GeographicLib">GeographicErr</a>(<span class="stringliteral">&quot;OSGB string &quot;</span> + gridref + <span class="stringliteral">&quot; too short&quot;</span>);
<a name="l00100"></a>00100     <span class="keywordflow">if</span> (len % 2)
<a name="l00101"></a>00101       <span class="keywordflow">throw</span> <a class="code" href="classGeographicLib_1_1GeographicErr.html" title="Exception handling for GeographicLib">GeographicErr</a>(<span class="stringliteral">&quot;OSGB string &quot;</span> + gridref +
<a name="l00102"></a>00102                           <span class="stringliteral">&quot; has odd number of characters&quot;</span>);
<a name="l00103"></a>00103     <span class="keywordtype">int</span>
<a name="l00104"></a>00104       xh = 0,
<a name="l00105"></a>00105       yh = 0;
<a name="l00106"></a>00106     <span class="keywordflow">while</span> (p &lt; 2) {
<a name="l00107"></a>00107       <span class="keywordtype">int</span> i = lookup(letters, grid[p++]);
<a name="l00108"></a>00108       <span class="keywordflow">if</span> (i &lt; 0)
<a name="l00109"></a>00109         <span class="keywordflow">throw</span> <a class="code" href="classGeographicLib_1_1GeographicErr.html" title="Exception handling for GeographicLib">GeographicErr</a>(<span class="stringliteral">&quot;Illegal prefix character &quot;</span> + gridref);
<a name="l00110"></a>00110       yh = yh * tilegrid + tilegrid - (i / tilegrid) - 1;
<a name="l00111"></a>00111       xh = xh * tilegrid + (i % tilegrid);
<a name="l00112"></a>00112     }
<a name="l00113"></a>00113     xh -= tileoffx;
<a name="l00114"></a>00114     yh -= tileoffy;
<a name="l00115"></a>00115 
<a name="l00116"></a>00116     <span class="keywordtype">int</span> prec1 = (len - p)/2;
<a name="l00117"></a>00117     real
<a name="l00118"></a>00118       unit = tile,
<a name="l00119"></a>00119       x1 = unit * xh,
<a name="l00120"></a>00120       y1 = unit * yh;
<a name="l00121"></a>00121     <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = 0; i &lt; prec1; ++i) {
<a name="l00122"></a>00122       unit /= base;
<a name="l00123"></a>00123       <span class="keywordtype">int</span>
<a name="l00124"></a>00124         ix = lookup(digits, grid[p + i]),
<a name="l00125"></a>00125         iy = lookup(digits, grid[p + i + prec1]);
<a name="l00126"></a>00126       <span class="keywordflow">if</span> (ix &lt; 0 || iy &lt; 0)
<a name="l00127"></a>00127         <span class="keywordflow">throw</span> <a class="code" href="classGeographicLib_1_1GeographicErr.html" title="Exception handling for GeographicLib">GeographicErr</a>(<span class="stringliteral">&quot;Encountered a non-digit in &quot;</span> + gridref);
<a name="l00128"></a>00128       x1 += unit * ix;
<a name="l00129"></a>00129       y1 += unit * iy;
<a name="l00130"></a>00130     }
<a name="l00131"></a>00131     <span class="keywordflow">if</span> (centerp) {
<a name="l00132"></a>00132       x1 += unit/2;
<a name="l00133"></a>00133       y1 += unit/2;
<a name="l00134"></a>00134     }
<a name="l00135"></a>00135     x = x1;
<a name="l00136"></a>00136     y = y1;
<a name="l00137"></a>00137     prec = prec1;
<a name="l00138"></a>00138   }
<a name="l00139"></a>00139 
<a name="l00140"></a>00140   <span class="keywordtype">void</span> OSGB::CheckCoords(<a class="code" href="Geod_8cpp.html#a5caf95d46b184d9ca1d3764b3781b3c9">real</a> x, <a class="code" href="Geod_8cpp.html#a5caf95d46b184d9ca1d3764b3781b3c9">real</a> y) {
<a name="l00141"></a>00141     <span class="comment">// Limits are all multiples of 100km and are all closed on the lower end</span>
<a name="l00142"></a>00142     <span class="comment">// and open on the upper end -- and this is reflected in the error</span>
<a name="l00143"></a>00143     <span class="comment">// messages.</span>
<a name="l00144"></a>00144     <span class="keywordflow">if</span> (! (x &gt;= minx &amp;&amp; x &lt; maxx) )
<a name="l00145"></a>00145       <span class="keywordflow">throw</span> <a class="code" href="classGeographicLib_1_1GeographicErr.html" title="Exception handling for GeographicLib">GeographicErr</a>(<span class="stringliteral">&quot;Easting &quot;</span> + str(<span class="keywordtype">int</span>(floor(x/1000)))
<a name="l00146"></a>00146                           + <span class="stringliteral">&quot;km not in OSGB range [&quot;</span>
<a name="l00147"></a>00147                           + str(minx/1000) + <span class="stringliteral">&quot;km, &quot;</span>
<a name="l00148"></a>00148                           + str(maxx/1000) + <span class="stringliteral">&quot;km)&quot;</span>);
<a name="l00149"></a>00149     <span class="keywordflow">if</span> (! (y &gt;= miny &amp;&amp; y &lt; maxy) )
<a name="l00150"></a>00150       <span class="keywordflow">throw</span> <a class="code" href="classGeographicLib_1_1GeographicErr.html" title="Exception handling for GeographicLib">GeographicErr</a>(<span class="stringliteral">&quot;Northing &quot;</span> + str(<span class="keywordtype">int</span>(floor(y/1000)))
<a name="l00151"></a>00151                           + <span class="stringliteral">&quot;km not in OSGB range [&quot;</span>
<a name="l00152"></a>00152                           + str(miny/1000) + <span class="stringliteral">&quot;km, &quot;</span>
<a name="l00153"></a>00153                           + str(maxy/1000) + <span class="stringliteral">&quot;km)&quot;</span>);
<a name="l00154"></a>00154   }
<a name="l00155"></a>00155 } <span class="comment">// namespace GeographicLib</span>
</pre></div></div>
</div>
<hr class="footer"/><address class="footer"><small>Generated on Tue Feb 22 2011 for GeographicLib by&nbsp;
<a href="http://www.doxygen.org/index.html">
<img class="footer" src="doxygen.png" alt="doxygen"/></a> 1.7.1 </small></address>
</body>
</html>