/*
 *    GeoTools - The Open Source Java GIS Toolkit
 *    http://geotools.org
 *
 *    (C) 2011, Open Source Geospatial Foundation (OSGeo)
 *    (C) 2008, Open Geospatial Consortium Inc.
 *    
 *    All Rights Reserved. http://www.opengis.org/legal/
 */
package org.opengis.style;

import org.opengis.annotation.Extension;
import org.opengis.annotation.XmlElement;
import org.opengis.filter.expression.Expression;


/**
 * Gives directions for how to draw lines on a map.
 *
 *
 * @source $URL: http://svn.osgeo.org/geotools/trunk/modules/library/opengis/src/main/java/org/opengis/style/LineSymbolizer.java $
 * @version <A HREF="http://www.opengeospatial.org/standards/symbol">Symbology Encoding Implementation Specification 1.1.0</A>
 * @author Open Geospatial Consortium
 * @author Johann Sorel (Geomatys)
 * @author Chris Dillard (SYS Technologies)
 * @since GeoAPI 2.2
 */
@XmlElement("LineSymbolizer")
public interface LineSymbolizer extends Symbolizer {

    /**
     * Returns the object containing all the information necessary to draw
     * styled lines.
     * @return Stroke object, contain information about how to draw lines
     */
    @XmlElement("Stroke")
    Stroke getStroke();

    /**
     * PerpendicularOffset allows to draw lines in parallel to the original geometry. For
     * complex line strings these parallel lines have to be constructed so that the distance
     * between original geometry and drawn line stays equal. This construction can result in
     * drawn lines that are actually smaller or longer than the original geometry.
     *
     * The distance is in uoms and is positive to the left-hand side of the line string. Negative
     * numbers mean right. The default offset is 0.

     * @return Expression
     */
    @XmlElement("PerpendicularOffset")
    Expression getPerpendicularOffset();
    
    /**
     * Calls the visit method of a StyleVisitor
     *
     * @param visitor the style visitor
     */
    @Extension
    Object accept(StyleVisitor visitor, Object extraData);

}