/*
 *    GeoTools - OpenSource mapping toolkit
 *    http://geotools.org
 *    (C) 2002-2006, GeoTools Project Managment Committee (PMC)
 *
 *    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;
 *    version 2.1 of the License.
 *
 *    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.
 */
package org.geotools.styling;

import org.opengis.filter.expression.Expression;
import org.geotools.event.GTComponent;


/**
 * An AnchorPoint identifies the location inside a textlabel to use as an
 * "anchor" for positioning it relative to a point geometry.
 *
 * @author Ian Turton
 * @source $URL: http://svn.geotools.org/geotools/tags/2.4.1/modules/library/api/src/main/java/org/geotools/styling/AnchorPoint.java $
 * @version $Id: AnchorPoint.java 25459 2007-05-08 05:19:25Z jgarnett $
 */
public interface AnchorPoint extends GTComponent {
    //TODO: add AnchorPoint to GeoAPI
    /**
     * get the x coordinate of the anchor point
     *
     * @return the expression which represents the X coordinate
     */
    Expression getAnchorPointX();

    /**
     * set the X coordinate for the anchor point
     *
     * @param x an expression which represents the X coordinate
     */
    void setAnchorPointX(Expression x);

    /**
     * get the y coordinate of the anchor point
     *
     * @return the expression which represents the Y coordinate
     */
    Expression getAnchorPointY();

    /**
     * set the Y coordinate for the anchor point
     *
     * @param y an expression which represents the Y coordinate
     */
    void setAnchorPointY(Expression y);

    /**
     * calls the visit method of a StyleVisitor
     *
     * @param visitor the style visitor
     */
    void accept(StyleVisitor visitor);
}
