com.vividsolutions.jtstest.function.LineHandlingFunctions Maven / Gradle / Ivy

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/*
 * The JTS Topology Suite is a collection of Java classes that
 * implement the fundamental operations required to validate a given
 * geo-spatial data set to a known topological specification.
 *
 * Copyright (C) 2001 Vivid Solutions
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * For more information, contact:
 *
 *     Vivid Solutions
 *     Suite #1A
 *     2328 Government Street
 *     Victoria BC  V8T 5G5
 *     Canada
 *
 *     (250)385-6040
 *     www.vividsolutions.com
 */
package com.vividsolutions.jtstest.function;

import java.util.*;
import com.vividsolutions.jts.algorithm.*;
import com.vividsolutions.jts.geom.*;
import com.vividsolutions.jts.geom.util.*;
import com.vividsolutions.jts.densify.*;
import com.vividsolutions.jts.dissolve.LineDissolver;
import com.vividsolutions.jts.operation.polygonize.*;
import com.vividsolutions.jts.operation.linemerge.*;

public class LineHandlingFunctions {
	
  public static Geometry mergeLines(Geometry g)
  {
    LineMerger merger = new LineMerger();
    merger.add(g);
    Collection lines = merger.getMergedLineStrings();
    return g.getFactory().buildGeometry(lines);
  }
  
  public static Geometry sequenceLines(Geometry g)
  {
    return LineSequencer.sequence(g);
  }
  
  public static Geometry extractLines(Geometry g)
  {
    List lines = LinearComponentExtracter.getLines(g);
    return g.getFactory().buildGeometry(lines);
  }
  public static Geometry extractSegments(Geometry g)
  {
    List lines = LinearComponentExtracter.getLines(g);
    List segments = new ArrayList();
    for (Iterator it = lines.iterator(); it.hasNext(); ) {
      LineString line = (LineString) it.next();
      for (int i = 1; i < line.getNumPoints(); i++) {
        LineString seg = g.getFactory().createLineString(
            new Coordinate[] { line.getCoordinateN(i-1), line.getCoordinateN(i) }       
          );
        segments.add(seg);
      }
    }
    return g.getFactory().buildGeometry(segments);
  }
  public static Geometry extractChains(Geometry g, int maxChainSize)
  {
    List lines = LinearComponentExtracter.getLines(g);
    List chains = new ArrayList();
    for (Iterator it = lines.iterator(); it.hasNext(); ) {
      LineString line = (LineString) it.next();
      for (int i = 0; i < line.getNumPoints() - 1; i += maxChainSize) {
        LineString chain = extractChain(line, i, maxChainSize);
        chains.add(chain);
      }
    }
    return g.getFactory().buildGeometry(chains);
  }
  
  private static LineString extractChain(LineString line, int index, int maxChainSize)
  {
    int size = maxChainSize + 1;
    if (index + size > line.getNumPoints()) 
      size = line.getNumPoints() - index;
    Coordinate[] pts = new Coordinate[size];
    for (int i = 0; i < size; i++) {
      pts[i] = line.getCoordinateN(index + i);
    }
    return line.getFactory().createLineString(pts);
  }
  
  public static Geometry dissolve(Geometry geom)
  {
    return LineDissolver.dissolve(geom);
  }

}