geo/tcElevationDifference.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 /**
  21  * @file tcElevationDifference.cpp
  22  * @brief Elevation map including void highlighting.
  23  */
  24
  25 #include "tcElevationDifference.h"
  26 #include "tcSrtmModel.h"
  27 #include "tcGeoImageData.h"
  28 #include "tcChannelConfigWidget.h"
  29
  30 #include <QVBoxLayout>
  31 #include <QLabel>
  32
  33 /*
  34  * Constructors + destructor
  35  */
  36
  37 /// Primary constructor.
  38 tcElevationDifference::tcElevationDifference(const tcGeoImageData* refImagery, tcChannel* reference, tcSrtmModel* dem, tcGeoImageData* imagery)
  39 : tcChannelDem(dem, imagery,
  40                tr("Elevation difference"),
  41                tr("Difference in elevation between primary and secondary DEM."))
  42 , m_referenceChannel(reference)
  43 , m_refTransform(imagery->texToGeo() * refImagery->geoToTex())
  44 , m_configWidget(0)
  45 , m_stdDeviation(-1.0f)
  46 {
  47 }
  48
  49 /// Destructor.
  50 tcElevationDifference::~tcElevationDifference()
  51 {
  52   delete m_configWidget;
  53 }
  54
  55 /*
  56  * Main image interface
  57  */
  58
  59 tcChannelConfigWidget* tcElevationDifference::configWidget()
  60 {
  61   if (0 == m_configWidget)
  62   {
  63     m_configWidget = new tcChannelConfigWidget();
  64     m_configWidget->setWindowTitle(tr("%1 Configuration").arg(name()));
  65
  66     QVBoxLayout* layout = new QVBoxLayout(m_configWidget);
  67
  68     QLabel* standardDeviation = new QLabel(tr("Standard deviation: %1 m").arg(m_stdDeviation), m_configWidget);
  69       layout->addWidget(standardDeviation);
  70       connect(this, SIGNAL(stdDeviationChanged(const QString&)), standardDeviation, SLOT(setText(const QString&)));
  71   }
  72   return m_configWidget;
  73 }
  74
  75 /*
  76  * Interface for derived class to implement
  77  */
  78
  79 void tcElevationDifference::roundPortion(double* x1, double* y1, double* x2, double* y2)
  80 {
  81 }
  82
  83 tcAbstractPixelData* tcElevationDifference::loadPortion(double x1, double y1, double x2, double y2, bool changed)
  84 {
  85   maths::Vector<2,double> xy1 = m_refTransform * maths::Vector<2,double>(x1,y1);
  86   maths::Vector<2,double> xy2 = m_refTransform * maths::Vector<2,double>(x2,y2);
  87   Reference<tcAbstractPixelData> channelData = m_referenceChannel->loadPortion(xy1[0], xy1[1], xy2[0], xy2[1], changed);
  88   int width = channelData->width();
  89   int height = channelData->height();
  90
  91   // Create a new pixel buffer
  92   tcPixelData<float>* data = new tcPixelData<float>(width, height);
  93   startProcessing("Diffing elevation data");
  94   int index = 0;
  95   double sum = 0.0;
  96   for (int j = 0; j < height; ++j)
  97   {
  98     progress((float)j/(height-1));
  99     for (int i = 0; i < width; ++i)
 100     {
 101       // Transform coordinates
 102       maths::Vector<2,float> coord(x1 + (x2-x1)*i / (width  - 1),
 103                                    y1 + (y2-y1)*j / (height - 1));
 104       tcGeo geoCoord = geoAt(coord);
 105
 106       // Get some elevation data
 107       bool accurate;
 108       float altitude1 = dem()[0].altitudeAt(geoCoord, true, &accurate);
 109       float altitude2 = dem()[1].altitudeAt(geoCoord, true, &accurate);
 110       float diff = altitude2 - altitude1;
 111       diff *= diff;
 112       sum += diff;
 113       data->buffer()[index] = diff/(500.0f*500.0f);
 114       ++index;
 115     }
 116   }
 117   m_stdDeviation = sqrt(sum/(width*height));
 118   emit stdDeviationChanged(tr("Standard deviation: %1 m").arg(m_stdDeviation));
 119   endProcessing();
 120   return data;
 121 }