001 //$HeadURL: svn+ssh://rbezema@svn.wald.intevation.org/deegree/base/branches/2.2_testing/src/org/deegree/graphics/sld/Halo.java $
002 /*---------------- FILE HEADER ------------------------------------------
003
004 This file is part of deegree.
005 Copyright (C) 2001-2008 by:
006 EXSE, Department of Geography, University of Bonn
007 http://www.giub.uni-bonn.de/deegree/
008 lat/lon GmbH
009 http://www.lat-lon.de
010
011 This library is free software; you can redistribute it and/or
012 modify it under the terms of the GNU Lesser General Public
013 License as published by the Free Software Foundation; either
014 version 2.1 of the License, or (at your option) any later version.
015
016 This library is distributed in the hope that it will be useful,
017 but WITHOUT ANY WARRANTY; without even the implied warranty of
018 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
019 Lesser General Public License for more details.
020
021 You should have received a copy of the GNU Lesser General Public
022 License along with this library; if not, write to the Free Software
023 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
024
025 Contact:
026
027 Andreas Poth
028 lat/lon GmbH
029 Aennchenstr. 19
030 53115 Bonn
031 Germany
032 E-Mail: poth@lat-lon.de
033
034 Prof. Dr. Klaus Greve
035 Department of Geography
036 University of Bonn
037 Meckenheimer Allee 166
038 53115 Bonn
039 Germany
040 E-Mail: greve@giub.uni-bonn.de
041
042
043 ---------------------------------------------------------------------------*/
044 package org.deegree.graphics.sld;
045
046 import org.deegree.framework.xml.Marshallable;
047 import org.deegree.model.feature.Feature;
048 import org.deegree.model.filterencoding.FilterEvaluationException;
049
050 /**
051 * Incarnation of a sld:Halo-element. A Halo is a type of Fill that is applied to the backgrounds of
052 * font glyphs. The use of halos greatly improves the readability of text labels.
053 * <p>
054 *
055 * @author <a href="mailto:poth@lat-lon.de">Andreas Poth </a>
056 * @author <a href="mailto:mschneider@lat-lon.de">Markus Schneider </a>
057 * @version $Revision: 9340 $ $Date: 2007-12-27 13:32:12 +0100 (Do, 27 Dez 2007) $
058 */
059
060 public class Halo implements Marshallable {
061
062 private Fill fill = null;
063
064 private ParameterValueType radius = null;
065
066 private Stroke stroke = null;
067
068 /**
069 * Create a new <tt>Halo</tt> -instance.
070 * <p>
071 *
072 * @param radius
073 * radius to be used for the halo, use null for a rectangle styled halo
074 * @param fill
075 * defines the fill style, use null for default style
076 * @param stroke
077 * defines the stroke style, use null for default style
078 */
079 Halo( ParameterValueType radius, Fill fill, Stroke stroke ) {
080 setRadius( radius );
081 setFill( fill );
082 setStroke( stroke );
083 }
084
085 /**
086 * A Fill allows area geometries to be filled. There are two types of fills: solid-color and
087 * repeated GraphicFill. In general, if a Fill element is omitted in its containing element, no
088 * fill will be rendered. The default is a solid 50%-gray (color "#808080") opaque fill.
089 * <p>
090 *
091 * @return the underlying <tt>Fill</tt> -object or null
092 *
093 */
094 public Fill getFill() {
095 return fill;
096 }
097
098 /**
099 * Sets the underlying <tt>Fill</tt> -instance.
100 * <p>
101 *
102 * @param fill
103 * defines the fill color and pattern
104 *
105 */
106 public void setFill( Fill fill ) {
107 this.fill = fill;
108 }
109
110 /**
111 * The Radius element gives the absolute size of a halo radius in pixels encoded as a
112 * floating-point number. The radius is taken from the outside edge of a font glyph to extend
113 * the area of coverage of the glyph (and the inside edge of holes in the glyphs). The halo of a
114 * text label is considered to be a single shape. The default radius is one pixel. Negative
115 * values are not allowed.
116 * <p>
117 *
118 * @return the radius definition as <tt>ParameterValueType</tt>, or null if it has not been
119 * specified
120 *
121 */
122 public ParameterValueType getRadius() {
123 return radius;
124 }
125
126 /**
127 * Sets the value for the radius of the halo.
128 * <p>
129 *
130 * @param radius
131 * radius to be used for the halo, use null for a rectangle styled halo
132 *
133 */
134 public void setRadius( ParameterValueType radius ) {
135 this.radius = radius;
136 }
137
138 /**
139 * The Radius element gives the absolute size of a halo radius in pixels encoded as a
140 * floating-point number. The radius is taken from the outside edge of a font glyph to extend
141 * the area of coverage of the glyph (and the inside edge of holes in the glyphs). The halo of a
142 * text label is considered to be a single shape. The default radius is one pixel. Negative
143 * values are not allowed.
144 * <p>
145 *
146 * @param feature
147 * specifies the <tt>Feature</tt> to be used for evaluation of the underlying
148 * 'sld:ParameterValueType'
149 * @return the radius value, or -1 if it has not been specified
150 * @throws FilterEvaluationException
151 * if the evaluation fails
152 */
153 public double getRadius( Feature feature )
154 throws FilterEvaluationException {
155 if ( radius == null ) {
156 return -1.0;
157 }
158
159 String stringValue = null;
160 double radiusVal;
161
162 try {
163 stringValue = radius.evaluate( feature );
164 radiusVal = Double.parseDouble( stringValue );
165 } catch ( NumberFormatException e ) {
166 throw new FilterEvaluationException( "Given value ('" + stringValue
167 + "') for radius of Halo does not denote a number." );
168 }
169
170 return radiusVal;
171 }
172
173 /**
174 * @see org.deegree.graphics.sld.Halo#getRadius(Feature)
175 * <p>
176 * @param radius
177 * radius to be set for the halo
178 */
179 public void setRadius( double radius ) {
180 ParameterValueType pvt = null;
181 if ( radius > 0 ) {
182 pvt = StyleFactory.createParameterValueType( "" + radius );
183 this.radius = pvt;
184 }
185 }
186
187 /**
188 * Returns the underlying <tt>Stroke</tt> -instance.
189 * <p>
190 *
191 * @return the underlying <tt>Stroke</tt> -object or null
192 *
193 */
194 public Stroke getStroke() {
195 return stroke;
196 }
197
198 /**
199 * Sets the underlying <tt>Stroke</tt> -instance.
200 * <p>
201 *
202 * @param stroke
203 * defines the stroke color and pattern
204 */
205 public void setStroke( Stroke stroke ) {
206 this.stroke = stroke;
207 }
208
209 /**
210 * exports the content of the Halo as XML formated String
211 *
212 * @return xml representation of the Halo
213 */
214 public String exportAsXML() {
215
216 StringBuffer sb = new StringBuffer( 1000 );
217 sb.append( "<Halo>" );
218 if ( radius != null ) {
219 sb.append( "<Radius>" );
220 sb.append( ( (Marshallable) radius ).exportAsXML() );
221 sb.append( "</Radius>" );
222 }
223 if ( fill != null ) {
224 sb.append( ( (Marshallable) fill ).exportAsXML() );
225 }
226 if ( stroke != null ) {
227 sb.append( ( (Marshallable) stroke ).exportAsXML() );
228 }
229 sb.append( "</Halo>" );
230
231 return sb.toString();
232 }
233
234 }