001// License: GPL. For details, see LICENSE file. 002package org.openstreetmap.josm.actions; 003 004import static org.openstreetmap.josm.gui.help.HelpUtil.ht; 005import static org.openstreetmap.josm.tools.I18n.tr; 006import static org.openstreetmap.josm.tools.I18n.trn; 007 008import java.awt.event.ActionEvent; 009import java.awt.event.KeyEvent; 010import java.util.ArrayList; 011import java.util.Arrays; 012import java.util.Collection; 013import java.util.Collections; 014import java.util.HashSet; 015import java.util.LinkedList; 016import java.util.List; 017import java.util.Set; 018 019import javax.swing.JOptionPane; 020import javax.swing.SwingUtilities; 021 022import org.openstreetmap.josm.Main; 023import org.openstreetmap.josm.command.ChangeCommand; 024import org.openstreetmap.josm.command.Command; 025import org.openstreetmap.josm.command.DeleteCommand; 026import org.openstreetmap.josm.command.SequenceCommand; 027import org.openstreetmap.josm.data.osm.DataSet; 028import org.openstreetmap.josm.data.osm.Node; 029import org.openstreetmap.josm.data.osm.OsmPrimitive; 030import org.openstreetmap.josm.data.osm.Way; 031import org.openstreetmap.josm.data.projection.Ellipsoid; 032import org.openstreetmap.josm.gui.HelpAwareOptionPane; 033import org.openstreetmap.josm.gui.HelpAwareOptionPane.ButtonSpec; 034import org.openstreetmap.josm.gui.MainApplication; 035import org.openstreetmap.josm.gui.Notification; 036import org.openstreetmap.josm.spi.preferences.Config; 037import org.openstreetmap.josm.tools.ImageProvider; 038import org.openstreetmap.josm.tools.Shortcut; 039 040/** 041 * Delete unnecessary nodes from a way 042 * @since 2575 043 */ 044public class SimplifyWayAction extends JosmAction { 045 046 /** 047 * Constructs a new {@code SimplifyWayAction}. 048 */ 049 public SimplifyWayAction() { 050 super(tr("Simplify Way"), "simplify", tr("Delete unnecessary nodes from a way."), 051 Shortcut.registerShortcut("tools:simplify", tr("Tool: {0}", tr("Simplify Way")), KeyEvent.VK_Y, Shortcut.SHIFT), true); 052 putValue("help", ht("/Action/SimplifyWay")); 053 } 054 055 protected boolean confirmWayWithNodesOutsideBoundingBox(List<? extends OsmPrimitive> primitives) { 056 return DeleteAction.checkAndConfirmOutlyingDelete(primitives, null); 057 } 058 059 protected void alertSelectAtLeastOneWay() { 060 SwingUtilities.invokeLater(() -> 061 new Notification( 062 tr("Please select at least one way to simplify.")) 063 .setIcon(JOptionPane.WARNING_MESSAGE) 064 .setDuration(Notification.TIME_SHORT) 065 .setHelpTopic(ht("/Action/SimplifyWay#SelectAWayToSimplify")) 066 .show() 067 ); 068 } 069 070 protected boolean confirmSimplifyManyWays(int numWays) { 071 ButtonSpec[] options = new ButtonSpec[] { 072 new ButtonSpec( 073 tr("Yes"), 074 new ImageProvider("ok"), 075 tr("Simplify all selected ways"), 076 null), 077 new ButtonSpec( 078 tr("Cancel"), 079 new ImageProvider("cancel"), 080 tr("Cancel operation"), 081 null) 082 }; 083 return 0 == HelpAwareOptionPane.showOptionDialog( 084 Main.parent, 085 tr("The selection contains {0} ways. Are you sure you want to simplify them all?", numWays), 086 tr("Simplify ways?"), 087 JOptionPane.WARNING_MESSAGE, 088 null, // no special icon 089 options, 090 options[0], 091 ht("/Action/SimplifyWay#ConfirmSimplifyAll") 092 ); 093 } 094 095 @Override 096 public void actionPerformed(ActionEvent e) { 097 DataSet ds = getLayerManager().getEditDataSet(); 098 ds.beginUpdate(); 099 try { 100 List<Way> ways = OsmPrimitive.getFilteredList(ds.getSelected(), Way.class); 101 ways.removeIf(OsmPrimitive::isIncomplete); 102 if (ways.isEmpty()) { 103 alertSelectAtLeastOneWay(); 104 return; 105 } else if (!confirmWayWithNodesOutsideBoundingBox(ways) || (ways.size() > 10 && !confirmSimplifyManyWays(ways.size()))) { 106 return; 107 } 108 109 Collection<Command> allCommands = new LinkedList<>(); 110 for (Way way: ways) { 111 SequenceCommand simplifyCommand = simplifyWay(way); 112 if (simplifyCommand == null) { 113 continue; 114 } 115 allCommands.add(simplifyCommand); 116 } 117 if (allCommands.isEmpty()) return; 118 SequenceCommand rootCommand = new SequenceCommand( 119 trn("Simplify {0} way", "Simplify {0} ways", allCommands.size(), allCommands.size()), 120 allCommands 121 ); 122 MainApplication.undoRedo.add(rootCommand); 123 } finally { 124 ds.endUpdate(); 125 } 126 } 127 128 /** 129 * Replies true if <code>node</code> is a required node which can't be removed 130 * in order to simplify the way. 131 * 132 * @param way the way to be simplified 133 * @param node the node to check 134 * @return true if <code>node</code> is a required node which can't be removed 135 * in order to simplify the way. 136 */ 137 protected static boolean isRequiredNode(Way way, Node node) { 138 boolean isRequired = node.isTagged(); 139 if (!isRequired) { 140 int frequency = Collections.frequency(way.getNodes(), node); 141 if ((way.getNode(0) == node) && (way.getNode(way.getNodesCount()-1) == node)) { 142 frequency = frequency - 1; // closed way closing node counted only once 143 } 144 isRequired = frequency > 1; 145 } 146 if (!isRequired) { 147 List<OsmPrimitive> parents = new LinkedList<>(); 148 parents.addAll(node.getReferrers()); 149 parents.remove(way); 150 isRequired = !parents.isEmpty(); 151 } 152 return isRequired; 153 } 154 155 /** 156 * Simplifies a way with default threshold (read from preferences). 157 * 158 * @param w the way to simplify 159 * @return The sequence of commands to run 160 * @since 6411 161 */ 162 public final SequenceCommand simplifyWay(Way w) { 163 return simplifyWay(w, Config.getPref().getDouble("simplify-way.max-error", 3.0)); 164 } 165 166 /** 167 * Simplifies a way with a given threshold. 168 * 169 * @param w the way to simplify 170 * @param threshold the max error threshold 171 * @return The sequence of commands to run 172 * @since 6411 173 */ 174 public static SequenceCommand simplifyWay(Way w, double threshold) { 175 int lower = 0; 176 int i = 0; 177 List<Node> newNodes = new ArrayList<>(w.getNodesCount()); 178 while (i < w.getNodesCount()) { 179 if (isRequiredNode(w, w.getNode(i))) { 180 // copy a required node to the list of new nodes. Simplify not possible 181 newNodes.add(w.getNode(i)); 182 i++; 183 lower++; 184 continue; 185 } 186 i++; 187 // find the longest sequence of not required nodes ... 188 while (i < w.getNodesCount() && !isRequiredNode(w, w.getNode(i))) { 189 i++; 190 } 191 // ... and simplify them 192 buildSimplifiedNodeList(w.getNodes(), lower, Math.min(w.getNodesCount()-1, i), threshold, newNodes); 193 lower = i; 194 i++; 195 } 196 197 // Closed way, check if the first node could also be simplified ... 198 if (newNodes.size() > 3 && newNodes.get(0) == newNodes.get(newNodes.size() - 1) && !isRequiredNode(w, newNodes.get(0))) { 199 final List<Node> l1 = Arrays.asList(newNodes.get(newNodes.size() - 2), newNodes.get(0), newNodes.get(1)); 200 final List<Node> l2 = new ArrayList<>(3); 201 buildSimplifiedNodeList(l1, 0, 2, threshold, l2); 202 if (!l2.contains(newNodes.get(0))) { 203 newNodes.remove(0); 204 newNodes.set(newNodes.size() - 1, newNodes.get(0)); // close the way 205 } 206 } 207 208 if (newNodes.size() == w.getNodesCount()) return null; 209 210 Set<Node> delNodes = new HashSet<>(); 211 delNodes.addAll(w.getNodes()); 212 delNodes.removeAll(newNodes); 213 214 if (delNodes.isEmpty()) return null; 215 216 Collection<Command> cmds = new LinkedList<>(); 217 Way newWay = new Way(w); 218 newWay.setNodes(newNodes); 219 cmds.add(new ChangeCommand(w, newWay)); 220 cmds.add(new DeleteCommand(w.getDataSet(), delNodes)); 221 w.getDataSet().clearSelection(delNodes); 222 return new SequenceCommand( 223 trn("Simplify Way (remove {0} node)", "Simplify Way (remove {0} nodes)", delNodes.size(), delNodes.size()), cmds); 224 } 225 226 /** 227 * Builds the simplified list of nodes for a way segment given by a lower index <code>from</code> 228 * and an upper index <code>to</code> 229 * 230 * @param wnew the way to simplify 231 * @param from the lower index 232 * @param to the upper index 233 * @param threshold the max error threshold 234 * @param simplifiedNodes list that will contain resulting nodes 235 */ 236 protected static void buildSimplifiedNodeList(List<Node> wnew, int from, int to, double threshold, List<Node> simplifiedNodes) { 237 238 Node fromN = wnew.get(from); 239 Node toN = wnew.get(to); 240 241 // Get max xte 242 int imax = -1; 243 double xtemax = 0; 244 for (int i = from + 1; i < to; i++) { 245 Node n = wnew.get(i); 246 // CHECKSTYLE.OFF: SingleSpaceSeparator 247 double xte = Math.abs(Ellipsoid.WGS84.a 248 * xtd(fromN.lat() * Math.PI / 180, fromN.lon() * Math.PI / 180, toN.lat() * Math.PI / 180, 249 toN.lon() * Math.PI / 180, n.lat() * Math.PI / 180, n.lon() * Math.PI / 180)); 250 // CHECKSTYLE.ON: SingleSpaceSeparator 251 if (xte > xtemax) { 252 xtemax = xte; 253 imax = i; 254 } 255 } 256 257 if (imax != -1 && xtemax >= threshold) { 258 // Segment cannot be simplified - try shorter segments 259 buildSimplifiedNodeList(wnew, from, imax, threshold, simplifiedNodes); 260 buildSimplifiedNodeList(wnew, imax, to, threshold, simplifiedNodes); 261 } else { 262 // Simplify segment 263 if (simplifiedNodes.isEmpty() || simplifiedNodes.get(simplifiedNodes.size()-1) != fromN) { 264 simplifiedNodes.add(fromN); 265 } 266 if (fromN != toN) { 267 simplifiedNodes.add(toN); 268 } 269 } 270 } 271 272 /* From Aviaton Formulary v1.3 273 * http://williams.best.vwh.net/avform.htm 274 */ 275 private static double dist(double lat1, double lon1, double lat2, double lon2) { 276 return 2 * Math.asin(Math.sqrt(Math.pow(Math.sin((lat1 - lat2) / 2), 2) + Math.cos(lat1) * Math.cos(lat2) 277 * Math.pow(Math.sin((lon1 - lon2) / 2), 2))); 278 } 279 280 private static double course(double lat1, double lon1, double lat2, double lon2) { 281 return Math.atan2(Math.sin(lon1 - lon2) * Math.cos(lat2), Math.cos(lat1) * Math.sin(lat2) - Math.sin(lat1) 282 * Math.cos(lat2) * Math.cos(lon1 - lon2)) 283 % (2 * Math.PI); 284 } 285 286 private static double xtd(double lat1, double lon1, double lat2, double lon2, double lat3, double lon3) { 287 double distAD = dist(lat1, lon1, lat3, lon3); 288 double crsAD = course(lat1, lon1, lat3, lon3); 289 double crsAB = course(lat1, lon1, lat2, lon2); 290 return Math.asin(Math.sin(distAD) * Math.sin(crsAD - crsAB)); 291 } 292 293 @Override 294 protected void updateEnabledState() { 295 updateEnabledStateOnCurrentSelection(); 296 } 297 298 @Override 299 protected void updateEnabledState(Collection<? extends OsmPrimitive> selection) { 300 updateEnabledStateOnModifiableSelection(selection); 301 } 302}