Application: gvSIG desktop

/* gvSIG. Sistema de Informaci?n Geogr?fica de la Generalitat Valenciana

 *

 * Copyright (C) 2005 IVER T.I. and Generalitat Valenciana.

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 2

 * of the License, or (at your option) any later version.

 *

 * This program 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 General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,USA.

 *

 * For more information, contact:

 *

 *  Generalitat Valenciana

 *   Conselleria d'Infraestructures i Transport

 *   Av. Blasco Ib??ez, 50

 *   46010 VALENCIA

 *   SPAIN

 *

 *      +34 963862235

 *   gvsig@gva.es

 *      www.gvsig.gva.es

 *

 *    or

 *

 *   IVER T.I. S.A

 *   Salamanca 50

 *   46005 Valencia

 *   Spain

 *

 *   +34 963163400

 *   dac@iver.es

 */

package org.gvsig.symbology.fmap.labeling.placements;

import java.awt.Rectangle;

import java.awt.geom.PathIterator;

import java.awt.geom.Point2D;

import java.util.ArrayList;

import java.util.Vector;

import java.util.logging.Level;

import java.util.logging.Logger;

import com.iver.cit.gvsig.fmap.core.FShape;

import com.iver.cit.gvsig.fmap.core.v02.FConverter;

import com.iver.cit.gvsig.fmap.rendering.styling.labeling.IPlacementConstraints;

import com.iver.cit.gvsig.fmap.rendering.styling.labeling.LabelClass;

import com.iver.cit.gvsig.fmap.rendering.styling.labeling.LabelLocationMetrics;

import com.iver.utiles.swing.threads.Cancellable;

import com.vividsolutions.jts.geom.Geometry;

import com.vividsolutions.jts.geom.Point;

public class PolygonPlacementParallel implements ILabelPlacement{

        public ArrayList<LabelLocationMetrics> guess(LabelClass lc, FShape shp,

                        IPlacementConstraints placementConstraints,

                        double cartographicSymbolSize, Cancellable cancel) {

                if (cancel.isCanceled()) return CannotPlaceLabel.NO_PLACES;

                Geometry geo = FConverter.java2d_to_jts(shp);

                double theta = 0;

                if (geo == null) {

                        return CannotPlaceLabel.NO_PLACES;

                }

                Point pJTS = geo.getCentroid();

                if (pJTS == null) {

                        Logger.getAnonymousLogger().log(Level.SEVERE, "no centroid could be found");

                        return CannotPlaceLabel.NO_PLACES;

                }

                Point2D startingPoint = new Point2D.Double(pJTS.getX(), pJTS.getY());

                // calculated with the Linear Regression technique

                PathIterator pi = shp.getPathIterator(null);

                Rectangle geomBounds = shp.getBounds();

                double sumx = 0, sumy = 0, sumxx = 0, sumyy = 0, sumxy = 0;

                double Sxx, Sxy, b, a;

                double[] coords = new double[6];

                int count = 0;

                // add points to the regression process

                Vector<Point2D> v = new Vector<Point2D>();

                while (!pi.isDone()) {

                        pi.currentSegment(coords);

                        Point2D p;

                        if (geomBounds.width > geomBounds.height)

                                p = new Point2D.Double(coords[0], coords[1]);

                        else

                                p = new Point2D.Double(coords[1], coords[0]);

                        v.addElement(p);

                        count++;

                        sumx += p.getX();

                        sumy += p.getY();

                        sumxx += p.getX()*p.getX();

                        sumyy += p.getY()*p.getY();

                        sumxy += p.getX()*p.getY();

                        pi.next();

                }

                // start regression

                double n = (double) count;

                Sxx = sumxx-sumx*sumx/n;

                Sxy = sumxy-sumx*sumy/n;

                b = Sxy/Sxx;

                a = (sumy-b*sumx)/n;

                boolean isVertical = false;

                if (geomBounds.width < geomBounds.height) {

                        if (b == 0) {

                                // force vertical (to avoid divide by zero)

                                isVertical = true;

                        } else {

                                // swap axes

                                double bAux = 1/b;

                                a = - a / b;

                                b = bAux;

                        }

                }

                if (isVertical){

                        theta = AbstractLinePlacement.HALF_PI;

                } else {

                        double p1x = 0;

                        double  p1y =geomBounds.height-a;

                        double  p2x = geomBounds.width;

                        double  p2y = geomBounds.height-

                        (a+geomBounds.width*b);

                        theta = -Math.atan(((p2y - p1y) / (p2x - p1x)) );

                }

                ArrayList<LabelLocationMetrics> guessed = new ArrayList<LabelLocationMetrics>();

                Rectangle labelBounds = lc.getBounds();

                double cosTheta = Math.cos(theta);

                double sinTheta = Math.sin(theta);

                double halfHeight = labelBounds.getHeight()*0.5;

                double halfWidth= labelBounds.getWidth()*0.5;

                double offsetX = - halfHeight * sinTheta + halfWidth*cosTheta;

                double offsetY = halfHeight * cosTheta + halfWidth*sinTheta;

                startingPoint.setLocation(startingPoint.getX() - offsetX,

                                startingPoint.getY() - offsetY);

                guessed.add(new LabelLocationMetrics(startingPoint, theta, true));

                return guessed;

        }

        public boolean isSuitableFor(IPlacementConstraints placementConstraints,

                        int shapeType) {

                if (shapeType == FShape.POLYGON) {

                        return placementConstraints.isParallel();

                }

                return false;

        }

}