arctohgt/arcToHgt.cpp

   1 /***************************************************************************
   2  *   This file is part of Tecorrec.                                        *
   3  *   Copyright 2008 James Hogan <james@albanarts.com>                      *
   4  *                                                                         *
   5  *   Tecorrec is free software: you can redistribute it and/or modify      *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation, either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   Tecorrec is distributed in the hope that it will be useful,           *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with Tecorrec.  If not, write to the Free Software Foundation,  *
  17  *   Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.   *
  18  ***************************************************************************/
  19
  20 #include <QString>
  21 #include <QByteArray>
  22 #include <QFile>
  23 #include <QRegExp>
  24 #include <QtDebug>
  25
  26 #include <cmath>
  27
  28 double readDouble(QFile& file)
  29 {
  30   QByteArray line = file.readLine();
  31   static QRegExp intLine("^\\s*\\w+\\s+([-+]?\\d+(\\.\\d+)?)\\s*$");
  32   if (intLine.exactMatch(line))
  33   {
  34     return intLine.cap(1).toDouble();
  35   }
  36   else
  37   {
  38     return -1;
  39   }
  40 }
  41
  42 int readInt(QFile& file)
  43 {
  44   QByteArray line = file.readLine();
  45   static QRegExp intLine("^\\s*\\w+\\s+([-+]?\\d+)\\s*$");
  46   if (intLine.exactMatch(line))
  47   {
  48     return intLine.cap(1).toInt();
  49   }
  50   else
  51   {
  52     return -1;
  53   }
  54 }
  55
  56 int arcToHgt(const QString filename)
  57 {
  58   qDebug() << "Reading" << filename;
  59
  60   // first open arcinfo file
  61   QFile af(filename);
  62   af.open(QIODevice::ReadOnly);
  63
  64   // and read the header info
  65   int ncols = readInt(af);
  66   int nrows = readInt(af);
  67   double xllcorner = readDouble(af);
  68   double yllcorner = readDouble(af);
  69   double cellsize = readDouble(af);
  70   int nodata_value = readInt(af);
  71
  72   // find corresponding HGT tiles
  73   int lonMin = (int)floor(xllcorner);
  74   int lonMax = (int)floor(xllcorner + cellsize*(ncols-1));
  75   int latMin = (int)floor(yllcorner);
  76   int latMax = (int)floor(yllcorner + cellsize*(nrows-1));
  77   int tilesX = 1+lonMax-lonMin;
  78   int tilesY = 1+latMax-latMin;
  79   QFile* srtm = new QFile[tilesX*tilesY];
  80   for (int lon = lonMin; lon <= lonMax; ++lon)
  81   {
  82     for (int lat = latMin; lat <= latMax; ++lat)
  83     {
  84       QString filename = QString("%3%4%5%6.hgt")
  85                                     .arg(lat >= 0 ? 'N' : 'S')
  86                                     .arg(abs(lat), 2, 10, QLatin1Char('0'))
  87                                     .arg(lon >= 0 ? 'E' : 'W')
  88                                     .arg(abs(lon), 3, 10, QLatin1Char('0'));
  89       int index = tilesX*(lat-latMin) + lon-lonMin;
  90       srtm[index].setFileName(filename);
  91       srtm[index].open(QIODevice::WriteOnly);
  92       // if it doesn't exist, initialize with void
  93       if (srtm[index].atEnd())
  94       {
  95         QDataStream stream(&srtm[index]);
  96         stream.setByteOrder(QDataStream::BigEndian);
  97         uint16_t sample = 0x8000;
  98         for (int i = 0; i < 1201*1201; ++i)
  99         {
 100           stream << sample;
 101         }
 102       }
 103     }
 104   }
 105
 106   // overwrite directly with new values
 107
 108   QTextStream in(&af);
 109   // go through the rows
 110   for (int row = 0; row < nrows; ++row)
 111   {
 112     int y = (int)floor(0.5 + yllcorner/cellsize - latMin/cellsize + nrows-1-row);
 113     int latDiv = y/1200;
 114     int latMod = y%1200;
 115     for (int col = 0; col < ncols; ++col)
 116     {
 117       int x = (int)floor(0.5 + xllcorner/cellsize - lonMin/cellsize + col);
 118       int lonDiv = x/1200;
 119       int lonMod = x%1200;
 120
 121       int value;
 122       in >> value;
 123       uint16_t sample = value;
 124
 125       bool inX = (lonDiv >= 0 && lonDiv < tilesX);
 126       bool inY = (latDiv >= 0 && latDiv < tilesY);
 127       bool inXm1 = (lonDiv > 0 && lonDiv <= tilesX);
 128       bool inYm1 = (latDiv > 0 && latDiv <= tilesY);
 129 #define FILEPOS(X,Y) (((1201-(Y))*1201 + (X))*2)
 130       if (inX && inY)
 131       {
 132         int index = latDiv*tilesX + lonDiv;
 133         QDataStream stream(&srtm[index]);
 134         stream.setByteOrder(QDataStream::BigEndian);
 135         srtm[index].seek(FILEPOS(lonMod, latMod));
 136         stream << sample;
 137       }
 138       bool edgeX = (lonMod == 0);
 139       bool edgeY = (latMod == 0);
 140       if (edgeX && inXm1 && inY)
 141       {
 142         int index = latDiv*tilesX + lonDiv-1;
 143         QDataStream stream(&srtm[index]);
 144         stream.setByteOrder(QDataStream::BigEndian);
 145         srtm[index].seek(FILEPOS(1200, latMod));
 146         stream << sample;
 147       }
 148       if (edgeY && inX && inYm1)
 149       {
 150         int index = (latDiv-1)*tilesX + lonDiv;
 151         QDataStream stream(&srtm[index]);
 152         stream.setByteOrder(QDataStream::BigEndian);
 153         srtm[index].seek(FILEPOS(lonMod, 1200));
 154         stream << sample;
 155       }
 156       if (edgeX && edgeY && inXm1 && inYm1)
 157       {
 158         int index = (latDiv-1)*tilesX + lonDiv-1;
 159         QDataStream stream(&srtm[index]);
 160         stream.setByteOrder(QDataStream::BigEndian);
 161         srtm[index].seek(FILEPOS(1200, 1200));
 162         stream << sample;
 163       }
 164     }
 165   }
 166
 167   delete [] srtm;
 168 }
 169
 170 int main(int argc, char** argv)
 171 {
 172   qDebug() << "Welcome to arcToHgt";
 173   int error = 0;
 174   // Convert the file in each argument to HGT, overwriting any existing data
 175   for (int i = 1; i < argc; ++i)
 176   {
 177     error |= arcToHgt(argv[i]);
 178   }
 179   return error;
 180 }