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Provides a single jar containing all JAI-tools modules which you can use instead of including individual modules in your project. Note: It does not include the Jiffle scripting language or Jiffle image operator.

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package jaitools.media.jai.contour;

import jaitools.jts.Utils;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

import com.vividsolutions.jts.geom.Coordinate;
import com.vividsolutions.jts.geom.LineString;
import com.vividsolutions.jts.operation.linemerge.LineMerger;

/**
 * A container for the segments collected by ContourOpImage. 
 * It will return them as merged lines eventually applying simplification procedures 
 * 
 * @author Andrea Aime - GeoSolutions
 */
class Segments {
    static final int MAX_SIZE = 16348; // this amounts to 130KB storage
    boolean simplify;
    double[] ordinates;
    int idx = 0;
    List result = new ArrayList();
    
    public Segments(boolean simplify) {
        this.simplify = simplify;
    }
    
    /**
     * Adds a segment to the mix
     * @param x1
     * @param y1
     * @param x2
     * @param y2
     */
    public void add(double x1, double y1, double x2, double y2) {
        if(ordinates == null) {
            ordinates = new double[512];
        } else if((idx + 4) > ordinates.length) {
            // reallocate
            double[] temp = new double[ordinates.length * 2];
            System.arraycopy(ordinates, 0, temp, 0, ordinates.length);
            ordinates = temp;
        }
        ordinates[idx++] = x1;
        ordinates[idx++] = y1;
        ordinates[idx++] = x2;
        ordinates[idx++] = y2;
        
        if(idx >= MAX_SIZE) {
            merge();
        }
    }
    
    /**
     * Returns the merged and eventually simplified segments
     * @return
     */
    public List getMergedSegments() {
        if(idx > 0) {
            merge();
            // release the part of the storage we don't need anymore
            ordinates = null;
        }
        return result;
    }

    /**
     * Merges and eventually simplifies all of the segments collected so far with the 
     * linestring collected so far
     */
    void merge() {
        // merge all the segments
        LineMerger merger = new LineMerger();
        for (int i = 0; i < idx;) {
            Coordinate p1 = new Coordinate(ordinates[i++], ordinates[i++]);
            Coordinate p2 = new Coordinate(ordinates[i++], ordinates[i++]);
            if(!p1.equals2D(p2)) {
                merger.add(Utils.getGeometryFactory().createLineString(new Coordinate[] {p1, p2}));
            }
        }
        // reset the counter, we offloaded all segments
        idx = 0;
        // add to the mix all lines that have not been merged so far
        // (we know linear rings are already complete so we skip them)
        for (LineString ls : result) {
            merger.add(ls);
        }
        // eventually simplify and add back the merged line strings
        Collection mergedLines = merger.getMergedLineStrings();
        result.clear();
        if(simplify) {
            for (LineString merged : mergedLines) {
                if(simplify) {
                    merged = Utils.removeCollinearVertices(merged);
                }
                result.add(merged);
            }
        } else {
            result.addAll(mergedLines);
        }
    }
}