Application: gvSIG desktop » gvSIG geoprocess

/*

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

 *

 * Copyright (C) 2010 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.

 *

 */

package org.gvsig.geoprocess.core;

import org.cresques.cts.IProjection;

import org.gvsig.andami.PluginServices;

import org.gvsig.andami.ui.mdiManager.IWindow;

import org.gvsig.app.project.documents.view.gui.AbstractViewPanel;

import org.gvsig.fmap.mapcontext.MapContext;

/**

 * Map utilities

 * @author <a href="mailto:nachobrodin@gmail.com">Nacho Brodin</a>

 */

public class MapTools {

        public static final double EARTH_RADIUS = 6378137d;

        /**

         * For computing with geodetic coordinates:

         * returns the angular measure (in radians)

         * for a distance over the earth along a

         * meridiam.

         * Because this consideration is an approximation,

         * we consideer the eart like an sphere (not an

         * ellipsoid)

         * @param dist distance in meters

         * @return arc of meridian whose length is the specified

         * distance

         */

        public static double toSexaAngularMeasure(double dist) {

                /*

                 *  dist = 6378km(terrestrial radius) -> 2PI

                 *  passed distance -> incognite

                 */

                return Math.toDegrees((2 * Math.PI * dist) / EARTH_RADIUS);

        }

        /**

         * Converts a distance entered by user in the GUI in the same distance

         * in internal units (measure units)

         *

         * */

        public static double getInInternalUnits(double userEntryDistance,

                                                                                                        IProjection proj,

                                                                                                        int distanceUnits,

                                                                                                        int mapUnits) {

                double[] trans2Meter = MapContext.getDistanceTrans2Meter();

                double distInInternalUnits = (userEntryDistance/trans2Meter[mapUnits]) *

                                                                trans2Meter[distanceUnits];

                if( (proj != null) && !(proj.isProjected())) 

                        distInInternalUnits = toSexaAngularMeasure(distInInternalUnits);

                return distInInternalUnits;

        }

        /**

         * <p>Gets the measurement unit used by this view port for the map.</p>

         *

         * @return Returns the current map measure unit

         */

        public static int getMapUnits() {

                IWindow w = PluginServices.getMDIManager().getActiveWindow();

                if(!(w instanceof AbstractViewPanel)) {

                        IWindow[] wList = PluginServices.getMDIManager().getAllWindows();

                        for (int i = 0; i < wList.length; i++) {

                                if(wList[i] instanceof AbstractViewPanel)

                                        w = (IWindow)wList[i];

                        }

                }

                if(w != null && w instanceof AbstractViewPanel) {

                        IProjection proj = ((AbstractViewPanel)w).getMapControl().getViewPort().getProjection();

                        if(proj.isProjected())

                                return ((AbstractViewPanel)w).getMapControl().getViewPort().getMapUnits();

                } 

                return 1;

        }

        /**

         * <p>Returns the measurement unit of this view port used for measuring distances and displaying information.</p>

         *

         * @return the measurement unit of this view used for measuring distances and displaying information

         */

        public static int getDistanceUnits() {

                IWindow w = PluginServices.getMDIManager().getActiveWindow();

                if(!(w instanceof AbstractViewPanel)) {

                        IWindow[] wList = PluginServices.getMDIManager().getAllWindows();

                        for (int i = 0; i < wList.length; i++) {

                                if(wList[i] instanceof AbstractViewPanel)

                                        w = (IWindow)wList[i];

                        }

                }

                if(w != null && w instanceof AbstractViewPanel)

                        return ((AbstractViewPanel)w).getMapControl().getViewPort().getDistanceUnits();

                else 

                        return 1;

        }

}