Application: gvSIG desktop » gvSIG tools: ToolBox

package es.unex.sextante.gridAnalysis.cva;

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 CVAAlgorithm

         extends

            GeoAlgorithm {

   public static final String A1    = "A1";

   public static final String A2    = "A2";

   public static final String B1    = "B1";

   public static final String B2    = "B2";

   public static final String ANGLE = "ANGLE";

   public static final String DIST  = "DIST";

   @Override

   public void defineCharacteristics() {

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

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

      setUserCanDefineAnalysisExtent(true);

      try {

         m_Parameters.addInputRasterLayer(A1, Sextante.getText("Layer_1__init"), true);

         m_Parameters.addInputRasterLayer(A2, Sextante.getText("Layer_2__init"), true);

         m_Parameters.addInputRasterLayer(B1, Sextante.getText("Layer_1__final"), true);

         m_Parameters.addInputRasterLayer(B2, Sextante.getText("Layer_2__final"), true);

         addOutputRasterLayer(ANGLE, Sextante.getText("Angle"));

         addOutputRasterLayer(DIST, Sextante.getText("Modulus"));

      }

      catch (final RepeatedParameterNameException e) {

         Sextante.addErrorToLog(e);

      }

   }

   @Override

   public boolean processAlgorithm() throws GeoAlgorithmExecutionException {

      int x, y;

      double dAngle, dDist;

      double a1, a2, b1, b2;

      int iNX, iNY;

      IRasterLayer layerA1, layerA2, layerB1, layerB2;

      IRasterLayer Angle, Distance;

      layerA1 = m_Parameters.getParameterValueAsRasterLayer(A1);

      layerA2 = m_Parameters.getParameterValueAsRasterLayer(A2);

      layerB1 = m_Parameters.getParameterValueAsRasterLayer(B1);

      layerB2 = m_Parameters.getParameterValueAsRasterLayer(B2);

      Distance = getNewRasterLayer(DIST, Sextante.getText("Modulus"), IRasterLayer.RASTER_DATA_TYPE_DOUBLE);

      Angle = getNewRasterLayer(ANGLE, Sextante.getText("Angle"), IRasterLayer.RASTER_DATA_TYPE_DOUBLE);

      final AnalysisExtent extent = Distance.getWindowGridExtent();

      layerA1.setWindowExtent(extent);

      layerA2.setWindowExtent(extent);

      layerB1.setWindowExtent(extent);

      layerB2.setWindowExtent(extent);

      iNX = extent.getNX();

      iNY = extent.getNY();

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

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

            a1 = layerA1.getCellValueAsDouble(x, y);

            a2 = layerA2.getCellValueAsDouble(x, y);

            b1 = layerB1.getCellValueAsDouble(x, y);

            b2 = layerB2.getCellValueAsDouble(x, y);

            if (layerA1.isNoDataValue(a1) || layerA2.isNoDataValue(a2) || layerB1.isNoDataValue(b1) || layerB2.isNoDataValue(b2)) {

               Distance.setNoData(x, y);

               Angle.setNoData(x, y);

            }

            else {

               dDist = Math.sqrt((a1 - a2) * (a1 - a2) + (b1 - b2) * (b1 - b2));

               dAngle = Math.atan((a1 - a2) / (b1 - b2));

               Distance.setCellValue(x, y, dDist);

               Angle.setCellValue(x, y, dAngle);

            }

         }

      }

      return !m_Task.isCanceled();

   }

}