Application: gvSIG desktop » gvSIG tools: ToolBox

package es.unex.sextante.morphometry.realArea;

import es.unex.sextante.core.GeoAlgorithm;

import es.unex.sextante.core.AnalysisExtent;

import es.unex.sextante.core.Sextante;

import es.unex.sextante.dataObjects.IRasterLayer;

import es.unex.sextante.exceptions.GeoAlgorithmExecutionException;

import es.unex.sextante.exceptions.RepeatedParameterNameException;

public class RealAreaAlgorithm

         extends

            GeoAlgorithm {

   public static final String DEM      = "DEM";

   public static final String REALAREA = "REALAREA";

   IRasterLayer               m_RealArea;

   IRasterLayer               m_DEM    = null;

   private double             m_DX2;

   @Override

   public boolean processAlgorithm() throws GeoAlgorithmExecutionException {

      int x, y;

      int iNX, iNY;

      m_DEM = m_Parameters.getParameterValueAsRasterLayer(DEM);

      m_RealArea = getNewRasterLayer(REALAREA, Sextante.getText("Real_area"), IRasterLayer.RASTER_DATA_TYPE_FLOAT);

      final AnalysisExtent extent = m_RealArea.getWindowGridExtent();

      m_DEM.setWindowExtent(extent);

      iNX = m_DEM.getNX();

      iNY = m_DEM.getNY();

      m_DX2 = m_DEM.getWindowCellSize() * m_DEM.getWindowCellSize();

      for (y = 0; (y < iNY) && setProgress(y, iNY); y++) {

         for (x = 0; x < iNX; x++) {

            setRealArea(x, y);

         }

      }

      return !m_Task.isCanceled();

   }

   @Override

   public void defineCharacteristics() {

      setUserCanDefineAnalysisExtent(true);

      setGroup(Sextante.getText("Geomorphometry_and_terrain_analysis"));

      setName(Sextante.getText("Real_area"));

      try {

         m_Parameters.addInputRasterLayer(DEM, Sextante.getText("Elevation"), true);

         addOutputRasterLayer(REALAREA, Sextante.getText("Real_area"));

      }

      catch (final RepeatedParameterNameException e) {

         Sextante.addErrorToLog(e);

      }

   }

   private void setRealArea(final int x,

                            final int y) {

      final double dSlope = m_DEM.getSlope(x, y);

      double dArea;

      if (!m_DEM.isNoDataValue(dSlope)) {

         dArea = m_DX2 / Math.cos(dSlope);

         m_RealArea.setCellValue(x, y, dArea);

      }

      else {

         m_RealArea.setNoData(x, y);

      }

   }

}