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 ImageProvider.get("ok"), 075 tr("Simplify all selected ways"), 076 null 077 ), 078 new ButtonSpec( 079 tr("Cancel"), 080 ImageProvider.get("cancel"), 081 tr("Cancel operation"), 082 null 083 ) 084 }; 085 return 0 == HelpAwareOptionPane.showOptionDialog( 086 Main.parent, 087 tr( 088 "The selection contains {0} ways. Are you sure you want to simplify them all?", 089 numWays 090 ), 091 tr("Simplify ways?"), 092 JOptionPane.WARNING_MESSAGE, 093 null, // no special icon 094 options, 095 options[0], 096 ht("/Action/SimplifyWay#ConfirmSimplifyAll") 097 ); 098 } 099 100 @Override 101 public void actionPerformed(ActionEvent e) { 102 DataSet ds = getLayerManager().getEditDataSet(); 103 ds.beginUpdate(); 104 try { 105 List<Way> ways = OsmPrimitive.getFilteredList(ds.getSelected(), Way.class); 106 ways.removeIf(OsmPrimitive::isIncomplete); 107 if (ways.isEmpty()) { 108 alertSelectAtLeastOneWay(); 109 return; 110 } else if (!confirmWayWithNodesOutsideBoundingBox(ways) || (ways.size() > 10 && !confirmSimplifyManyWays(ways.size()))) { 111 return; 112 } 113 114 Collection<Command> allCommands = new LinkedList<>(); 115 for (Way way: ways) { 116 SequenceCommand simplifyCommand = simplifyWay(way); 117 if (simplifyCommand == null) { 118 continue; 119 } 120 allCommands.add(simplifyCommand); 121 } 122 if (allCommands.isEmpty()) return; 123 SequenceCommand rootCommand = new SequenceCommand( 124 trn("Simplify {0} way", "Simplify {0} ways", allCommands.size(), allCommands.size()), 125 allCommands 126 ); 127 MainApplication.undoRedo.add(rootCommand); 128 } finally { 129 ds.endUpdate(); 130 } 131 } 132 133 /** 134 * Replies true if <code>node</code> is a required node which can't be removed 135 * in order to simplify the way. 136 * 137 * @param way the way to be simplified 138 * @param node the node to check 139 * @return true if <code>node</code> is a required node which can't be removed 140 * in order to simplify the way. 141 */ 142 protected static boolean isRequiredNode(Way way, Node node) { 143 boolean isRequired = node.isTagged(); 144 if (!isRequired) { 145 int frequency = Collections.frequency(way.getNodes(), node); 146 if ((way.getNode(0) == node) && (way.getNode(way.getNodesCount()-1) == node)) { 147 frequency = frequency - 1; // closed way closing node counted only once 148 } 149 isRequired = frequency > 1; 150 } 151 if (!isRequired) { 152 List<OsmPrimitive> parents = new LinkedList<>(); 153 parents.addAll(node.getReferrers()); 154 parents.remove(way); 155 isRequired = !parents.isEmpty(); 156 } 157 return isRequired; 158 } 159 160 /** 161 * Simplifies a way with default threshold (read from preferences). 162 * 163 * @param w the way to simplify 164 * @return The sequence of commands to run 165 * @since 6411 166 */ 167 public final SequenceCommand simplifyWay(Way w) { 168 return simplifyWay(w, Config.getPref().getDouble("simplify-way.max-error", 3.0)); 169 } 170 171 /** 172 * Simplifies a way with a given threshold. 173 * 174 * @param w the way to simplify 175 * @param threshold the max error threshold 176 * @return The sequence of commands to run 177 * @since 6411 178 */ 179 public static SequenceCommand simplifyWay(Way w, double threshold) { 180 int lower = 0; 181 int i = 0; 182 List<Node> newNodes = new ArrayList<>(w.getNodesCount()); 183 while (i < w.getNodesCount()) { 184 if (isRequiredNode(w, w.getNode(i))) { 185 // copy a required node to the list of new nodes. Simplify not possible 186 newNodes.add(w.getNode(i)); 187 i++; 188 lower++; 189 continue; 190 } 191 i++; 192 // find the longest sequence of not required nodes ... 193 while (i < w.getNodesCount() && !isRequiredNode(w, w.getNode(i))) { 194 i++; 195 } 196 // ... and simplify them 197 buildSimplifiedNodeList(w.getNodes(), lower, Math.min(w.getNodesCount()-1, i), threshold, newNodes); 198 lower = i; 199 i++; 200 } 201 202 // Closed way, check if the first node could also be simplified ... 203 if (newNodes.size() > 3 && newNodes.get(0) == newNodes.get(newNodes.size() - 1) && !isRequiredNode(w, newNodes.get(0))) { 204 final List<Node> l1 = Arrays.asList(newNodes.get(newNodes.size() - 2), newNodes.get(0), newNodes.get(1)); 205 final List<Node> l2 = new ArrayList<>(3); 206 buildSimplifiedNodeList(l1, 0, 2, threshold, l2); 207 if (!l2.contains(newNodes.get(0))) { 208 newNodes.remove(0); 209 newNodes.set(newNodes.size() - 1, newNodes.get(0)); // close the way 210 } 211 } 212 213 if (newNodes.size() == w.getNodesCount()) return null; 214 215 Set<Node> delNodes = new HashSet<>(); 216 delNodes.addAll(w.getNodes()); 217 delNodes.removeAll(newNodes); 218 219 if (delNodes.isEmpty()) return null; 220 221 Collection<Command> cmds = new LinkedList<>(); 222 Way newWay = new Way(w); 223 newWay.setNodes(newNodes); 224 cmds.add(new ChangeCommand(w, newWay)); 225 cmds.add(new DeleteCommand(w.getDataSet(), delNodes)); 226 w.getDataSet().clearSelection(delNodes); 227 return new SequenceCommand( 228 trn("Simplify Way (remove {0} node)", "Simplify Way (remove {0} nodes)", delNodes.size(), delNodes.size()), cmds); 229 } 230 231 /** 232 * Builds the simplified list of nodes for a way segment given by a lower index <code>from</code> 233 * and an upper index <code>to</code> 234 * 235 * @param wnew the way to simplify 236 * @param from the lower index 237 * @param to the upper index 238 * @param threshold the max error threshold 239 * @param simplifiedNodes list that will contain resulting nodes 240 */ 241 protected static void buildSimplifiedNodeList(List<Node> wnew, int from, int to, double threshold, List<Node> simplifiedNodes) { 242 243 Node fromN = wnew.get(from); 244 Node toN = wnew.get(to); 245 246 // Get max xte 247 int imax = -1; 248 double xtemax = 0; 249 for (int i = from + 1; i < to; i++) { 250 Node n = wnew.get(i); 251 // CHECKSTYLE.OFF: SingleSpaceSeparator 252 double xte = Math.abs(Ellipsoid.WGS84.a 253 * xtd(fromN.lat() * Math.PI / 180, fromN.lon() * Math.PI / 180, toN.lat() * Math.PI / 180, 254 toN.lon() * Math.PI / 180, n.lat() * Math.PI / 180, n.lon() * Math.PI / 180)); 255 // CHECKSTYLE.ON: SingleSpaceSeparator 256 if (xte > xtemax) { 257 xtemax = xte; 258 imax = i; 259 } 260 } 261 262 if (imax != -1 && xtemax >= threshold) { 263 // Segment cannot be simplified - try shorter segments 264 buildSimplifiedNodeList(wnew, from, imax, threshold, simplifiedNodes); 265 buildSimplifiedNodeList(wnew, imax, to, threshold, simplifiedNodes); 266 } else { 267 // Simplify segment 268 if (simplifiedNodes.isEmpty() || simplifiedNodes.get(simplifiedNodes.size()-1) != fromN) { 269 simplifiedNodes.add(fromN); 270 } 271 if (fromN != toN) { 272 simplifiedNodes.add(toN); 273 } 274 } 275 } 276 277 /* From Aviaton Formulary v1.3 278 * http://williams.best.vwh.net/avform.htm 279 */ 280 private static double dist(double lat1, double lon1, double lat2, double lon2) { 281 return 2 * Math.asin(Math.sqrt(Math.pow(Math.sin((lat1 - lat2) / 2), 2) + Math.cos(lat1) * Math.cos(lat2) 282 * Math.pow(Math.sin((lon1 - lon2) / 2), 2))); 283 } 284 285 private static double course(double lat1, double lon1, double lat2, double lon2) { 286 return Math.atan2(Math.sin(lon1 - lon2) * Math.cos(lat2), Math.cos(lat1) * Math.sin(lat2) - Math.sin(lat1) 287 * Math.cos(lat2) * Math.cos(lon1 - lon2)) 288 % (2 * Math.PI); 289 } 290 291 private static double xtd(double lat1, double lon1, double lat2, double lon2, double lat3, double lon3) { 292 double distAD = dist(lat1, lon1, lat3, lon3); 293 double crsAD = course(lat1, lon1, lat3, lon3); 294 double crsAB = course(lat1, lon1, lat2, lon2); 295 return Math.asin(Math.sin(distAD) * Math.sin(crsAD - crsAB)); 296 } 297 298 @Override 299 protected void updateEnabledState() { 300 updateEnabledStateOnCurrentSelection(); 301 } 302 303 @Override 304 protected void updateEnabledState(Collection<? extends OsmPrimitive> selection) { 305 updateEnabledStateOnModifiableSelection(selection); 306 } 307}