001 //$HeadURL: svn+ssh://rbezema@svn.wald.intevation.org/deegree/base/tags/2.1/src/org/deegree/graphics/displayelements/LabelDisplayElement.java $
002 /*---------------- FILE HEADER ------------------------------------------
003
004 This file is part of deegree.
005 Copyright (C) 2001-2007 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.displayelements;
045
046 import java.awt.Graphics;
047 import java.awt.Graphics2D;
048 import java.io.Serializable;
049 import java.util.ArrayList;
050 import java.util.Iterator;
051
052 import org.deegree.graphics.sld.ParameterValueType;
053 import org.deegree.graphics.sld.TextSymbolizer;
054 import org.deegree.graphics.transformation.GeoTransform;
055 import org.deegree.model.feature.Feature;
056 import org.deegree.model.spatialschema.Geometry;
057
058 /**
059 * <tt>DisplayElement</tt> that encapsulates a <tt>GM_Object</tt> (geometry), a
060 * <tt>ParameterValueType</tt> (caption) and a <tt>TextSymbolizer</tt> (style).
061 * <p>
062 * The graphical (say: screen) representations of this <tt>DisplayElement</tt> are <tt>Label</tt>-instances.
063 * These are generated either when the <tt>paint</tt>-method is called or assigned externally
064 * using the <tt>setLabels</tt>- or <tt>addLabels</tt>-methods.
065 * </p>
066 *
067 * @author <a href="mailto:poth@lat-lon.de">Andreas Poth</a>
068 * @author <a href="mailto:mschneider@lat-lon.de">Markus Schneider</a>
069 * @version $Revision: 6768 $ $Date: 2007-05-03 11:32:51 +0200 (Do, 03 Mai 2007) $
070 */
071
072 public class LabelDisplayElement extends GeometryDisplayElement implements DisplayElement, Serializable {
073
074 /** Use serialVersionUID for interoperability. */
075 private final static long serialVersionUID = -7870967255670858503L;
076
077 private ParameterValueType label = null;
078
079 // null means that the labels have to be created inside the paint-method
080 // (and have not been set externally)
081 private ArrayList<Label> labels = null;
082
083 /**
084 * Creates a new LabelDisplayElement object.
085 * <p>
086 *
087 * @param feature
088 * associated <tt>Feature</tt>
089 * @param geometry
090 * associated <tt>GM_Object</tt>
091 * @param symbolizer
092 * associated <tt>TextSymbolizer</tt>
093 */
094 public LabelDisplayElement( Feature feature, Geometry geometry, TextSymbolizer symbolizer ) {
095 super( feature, geometry, symbolizer );
096 setLabel( symbolizer.getLabel() );
097 }
098
099 /**
100 * Sets the caption of the label.
101 *
102 * @param label
103 */
104 public void setLabel( ParameterValueType label ) {
105 this.label = label;
106 }
107
108 /**
109 * Returns the caption of the label as <tt>ParameterValueType<tt>.
110 * @return label
111 */
112 public ParameterValueType getLabel() {
113 return label;
114 }
115
116 /**
117 * Renders the <tt>DisplayElement</tt> to the submitted graphic context. If the <tt>Label</tt>-represenations
118 * have been assigned externally, these labels are used, else <tt>Label</tt>-instances are
119 * created automatically using the <tt>LabelFactory</tt>.
120 * <p>
121 *
122 * @param g
123 * <tt>Graphics</tt> context to be used
124 * @param projection
125 * <tt>GeoTransform</tt> to be used
126 */
127 public void paint( Graphics g, GeoTransform projection, double scale ) {
128
129 ( (ScaledFeature) feature ).setScale( scale );
130 if ( label == null )
131 return;
132 Graphics2D g2D = (Graphics2D) g;
133 if ( labels == null ) {
134 try {
135 setLabels( LabelFactory.createLabels( this, projection, g2D ) );
136 } catch ( Exception e ) {
137 e.printStackTrace();
138 }
139 }
140 // paint all labels
141 Iterator it = labels.iterator();
142 while ( it.hasNext() ) {
143 Label lab = (Label) it.next();
144 lab.paint( g2D );
145 }
146
147 // mark the labels as unset (for the next paint-call)
148 labels = null;
149 }
150
151 /**
152 * Returns whether the <tt>DisplayElement</tt> should be painted at the current scale or not.
153 *
154 * @param scale
155 * @return applies scale constraint
156 */
157 public boolean doesScaleConstraintApply( double scale ) {
158 return ( symbolizer.getMinScaleDenominator() <= scale ) && ( symbolizer.getMaxScaleDenominator() > scale );
159 }
160
161 /**
162 * Removes all <tt>Label<tt> representations for this
163 * <tt>LabelDisplayElement</tt>.
164 */
165 public void clearLabels() {
166 labels = null;
167 }
168
169 /**
170 * Adds a <tt>Label</tt> representation that is to be considered when the
171 * <tt>LabelDisplayElement</tt> is painted to the view.
172 *
173 * @param label
174 */
175 public void addLabel( Label label ) {
176 if ( labels == null ) {
177 labels = new ArrayList<Label>( 100 );
178 }
179 labels.add( label );
180 }
181
182 /**
183 * Adds <tt>Label</tt> representations that are to be considered when the
184 * <tt>LabelDisplayElement</tt> is painted to the view.
185 *
186 * @param labels
187 */
188 public void addLabels( Label[] labels ) {
189 if ( this.labels == null ) {
190 this.labels = new ArrayList<Label>( 100 );
191 }
192 for ( int i = 0; i < labels.length; i++ ) {
193 this.labels.add( labels[i] );
194 }
195 }
196
197 /**
198 * Sets the <tt>Label</tt> representations that are to be considered when the
199 * <tt>LabelDisplayElement</tt> is painted to the view.
200 *
201 * @param labels
202 */
203 public void setLabels( Label[] labels ) {
204 this.labels = new ArrayList<Label>( 100 );
205 for ( int i = 0; i < labels.length; i++ ) {
206 this.labels.add( labels[i] );
207 }
208 }
209 }