Application: gvSIG desktop » gvSIG tools: ToolBox

package es.unex.sextante.vectorTools.voronoi;

import java.util.ArrayList;

import com.vividsolutions.jts.geom.Geometry;

import com.vividsolutions.jts.geom.GeometryFactory;

import com.vividsolutions.jts.triangulate.VoronoiDiagramBuilder;

import es.unex.sextante.additionalInfo.AdditionalInfoVectorLayer;

import es.unex.sextante.core.GeoAlgorithm;

import es.unex.sextante.core.Sextante;

import es.unex.sextante.dataObjects.IFeature;

import es.unex.sextante.dataObjects.IFeatureIterator;

import es.unex.sextante.dataObjects.IVectorLayer;

import es.unex.sextante.dataObjects.vectorFilters.BoundingBoxFilter;

import es.unex.sextante.exceptions.GeoAlgorithmExecutionException;

import es.unex.sextante.exceptions.RepeatedParameterNameException;

import es.unex.sextante.outputs.OutputVectorLayer;

public class VoronoiAlgorithm

         extends

            GeoAlgorithm {

   public static final String POINTS    = "POINTS";

   public static final String TRIANGLES = "TRIANGLES";

   private IVectorLayer       m_Points;

   private IVectorLayer       m_Voronoi;

   @Override

   public void defineCharacteristics() {

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

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

      setUserCanDefineAnalysisExtent(true);

      try {

         m_Parameters.addInputVectorLayer(POINTS, Sextante.getText("Points_layer"), AdditionalInfoVectorLayer.SHAPE_TYPE_POINT,

                  true);

         addOutputVectorLayer(TRIANGLES, Sextante.getText("Voronoi_polygons"), OutputVectorLayer.SHAPE_TYPE_POLYGON);

      }

      catch (final RepeatedParameterNameException e) {

         Sextante.addErrorToLog(e);

      }

   }

   @Override

   public boolean processAlgorithm() throws GeoAlgorithmExecutionException {

      int i;

      final int iShapeCount;

      m_Points = m_Parameters.getParameterValueAsVectorLayer(POINTS);

      if (!m_bIsAutoExtent) {

         m_Points.addFilter(new BoundingBoxFilter(m_AnalysisExtent));

      }

      final Class types[] = { Integer.class };

      final String sNames[] = { "ID" };

      m_Voronoi = getNewVectorLayer(TRIANGLES, Sextante.getText("Voronoi_polygons"), IVectorLayer.SHAPE_TYPE_POLYGON, types,

               sNames);

      i = 0;

      final ArrayList<Geometry> list = new ArrayList<Geometry>();

      iShapeCount = m_Points.getShapesCount();

      final IFeatureIterator iter = m_Points.iterator();

      while (iter.hasNext() && setProgress(i, iShapeCount)) {

         final IFeature feature = iter.next();

         list.add(feature.getGeometry());

         i++;

      }

      iter.close();

      m_Task.setDeterminate(false);

      final GeometryFactory gf = new GeometryFactory();

      final Geometry geomcol = gf.createGeometryCollection(list.toArray(new Geometry[0]));

      final VoronoiDiagramBuilder voronoi = new VoronoiDiagramBuilder();

      voronoi.setSites(geomcol);

      final Geometry polygons = voronoi.getDiagram(gf);

      final int iPolygons = polygons.getNumGeometries();

      for (int iPolygon = 0; iPolygon < iPolygons; iPolygon++) {

         final Geometry triangle = polygons.getGeometryN(iPolygon);

         final Object[] record = { new Integer(iPolygon) };

         m_Voronoi.addFeature(triangle, record);

      }

      return !m_Task.isCanceled();

   }

}