Application: gvSIG desktop

/**

 * gvSIG. Desktop Geographic Information System.

 *

 * Copyright (C) 2007-2013 gvSIG Association.

 *

 * 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 3

 * 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., 51 Franklin Street, Fifth Floor, Boston,

 * MA  02110-1301, USA.

 *

 * For any additional information, do not hesitate to contact us

 * at info AT gvsig.com, or visit our website www.gvsig.com.

 */

package org.gvsig.fmap.geom.operation.perpendicular;

import org.gvsig.fmap.geom.Geometry;

import org.gvsig.fmap.geom.Geometry.SUBTYPES;

import org.gvsig.fmap.geom.GeometryLocator;

import org.gvsig.fmap.geom.GeometryManager;

import org.gvsig.fmap.geom.exception.CreateGeometryException;

import org.gvsig.fmap.geom.operation.GeometryOperation;

import org.gvsig.fmap.geom.operation.GeometryOperationContext;

import org.gvsig.fmap.geom.operation.GeometryOperationException;

import org.gvsig.fmap.geom.operation.GeometryOperationNotSupportedException;

import org.gvsig.fmap.geom.primitive.Point;

/**

 * Gets a point that is located to a concrete distance (attribute distance)

 * of a line and is located in a perpendicular line that intersects with other 

 * point (attribute perpendicularPoint).

 * 

 * @author gvSIG Team

 * @version $Id$

 *

 */

public class PerpendicularPoint extends GeometryOperation{

    public static final String NAME = "perpendicularPoint";

    private static GeometryManager geomManager = GeometryLocator.getGeometryManager();

    public static final int CODE = geomManager.getGeometryOperationCode(NAME);

    public Object invoke(Geometry geom, GeometryOperationContext ctx)

        throws GeometryOperationException {

        Point perpendicularPoint = (Point)ctx.getAttribute(PerpendicularPointOperationContext.PERPENDICULAR_POINT); 

        double dist =

            ((Double) ctx

                .getAttribute(PerpendicularPointOperationContext.DISTANCE))

                .doubleValue();

        try {

            Point[] p = (Point[])geom.invokeOperation(Perpendicular.CODE, ctx);

            Point unit = (Point)geom.invokeOperation(UnitVector.CODE, ctx);

            return  geomManager.createPoint(perpendicularPoint.getX() + (unit.getX() * dist),

                perpendicularPoint.getY() + (unit.getY() * dist), SUBTYPES.GEOM2D);

        } catch (GeometryOperationNotSupportedException e) {

            throw new GeometryOperationException(e);

        } catch (CreateGeometryException e) {

            throw new GeometryOperationException(e);

        }

    }

    public int getOperationIndex() {      

        return CODE;

    }    

}