001// License: GPL. For details, see LICENSE file. 002package org.openstreetmap.josm.actions.mapmode; 003 004import java.util.ArrayList; 005import java.util.Collection; 006import java.util.Collections; 007import java.util.HashMap; 008import java.util.HashSet; 009import java.util.List; 010import java.util.Map; 011import java.util.Set; 012 013import org.openstreetmap.josm.Main; 014import org.openstreetmap.josm.actions.CombineWayAction; 015import org.openstreetmap.josm.command.AddCommand; 016import org.openstreetmap.josm.command.Command; 017import org.openstreetmap.josm.command.SequenceCommand; 018import org.openstreetmap.josm.data.coor.EastNorth; 019import org.openstreetmap.josm.data.osm.Node; 020import org.openstreetmap.josm.data.osm.Way; 021import org.openstreetmap.josm.tools.Geometry; 022 023/** 024 * Helper for ParallelWayAction 025 * 026 * @author Ole Jørgen Brønner (olejorgenb) 027 */ 028public class ParallelWays { 029 private final List<Way> ways; 030 private final List<Node> sortedNodes; 031 032 private final int nodeCount; 033 034 private final EastNorth[] pts; 035 private final EastNorth[] normals; 036 037 // Need a reference way to determine the direction of the offset when we manage multiple ways 038 public ParallelWays(Collection<Way> sourceWays, boolean copyTags, int refWayIndex) { 039 // Possible/sensible to use PrimetiveDeepCopy here? 040 041 // Make a deep copy of the ways, keeping the copied ways connected 042 // TODO: This assumes the first/last nodes of the ways are the only possible shared nodes. 043 Map<Node, Node> splitNodeMap = new HashMap<>(sourceWays.size()); 044 for (Way w : sourceWays) { 045 if (!splitNodeMap.containsKey(w.firstNode())) { 046 splitNodeMap.put(w.firstNode(), copyNode(w.firstNode(), copyTags)); 047 } 048 if (!splitNodeMap.containsKey(w.lastNode())) { 049 splitNodeMap.put(w.lastNode(), copyNode(w.lastNode(), copyTags)); 050 } 051 } 052 ways = new ArrayList<>(sourceWays.size()); 053 for (Way w : sourceWays) { 054 Way wCopy = new Way(); 055 wCopy.addNode(splitNodeMap.get(w.firstNode())); 056 for (int i = 1; i < w.getNodesCount() - 1; i++) { 057 wCopy.addNode(copyNode(w.getNode(i), copyTags)); 058 } 059 wCopy.addNode(splitNodeMap.get(w.lastNode())); 060 if (copyTags) { 061 wCopy.setKeys(w.getKeys()); 062 } 063 ways.add(wCopy); 064 } 065 066 // Find a linear ordering of the nodes. Fail if there isn't one. 067 CombineWayAction.NodeGraph nodeGraph = CombineWayAction.NodeGraph.createUndirectedGraphFromNodeWays(ways); 068 List<Node> sortedNodesPath = nodeGraph.buildSpanningPath(); 069 if (sortedNodesPath == null) 070 throw new IllegalArgumentException("Ways must have spanning path"); // Create a dedicated exception? 071 072 // Fix #8631 - Remove duplicated nodes from graph to be robust with self-intersecting ways 073 Set<Node> removedNodes = new HashSet<>(); 074 sortedNodes = new ArrayList<>(); 075 for (int i = 0; i < sortedNodesPath.size(); i++) { 076 Node n = sortedNodesPath.get(i); 077 if (i < sortedNodesPath.size()-1 && sortedNodesPath.get(i+1).getCoor().equals(n.getCoor())) { 078 removedNodes.add(n); 079 for (Way w : ways) { 080 w.removeNode(n); 081 } 082 continue; 083 } 084 if (!removedNodes.contains(n)) { 085 sortedNodes.add(n); 086 } 087 } 088 089 // Ugly method of ensuring that the offset isn't inverted. I'm sure there is a better and more elegant way 090 Way refWay = ways.get(refWayIndex); 091 boolean refWayReversed = true; 092 for (int i = 0; i < sortedNodes.size() - 1; i++) { 093 if (sortedNodes.get(i) == refWay.firstNode() && sortedNodes.get(i + 1) == refWay.getNode(1)) { 094 refWayReversed = false; 095 break; 096 } 097 } 098 if (refWayReversed) { 099 Collections.reverse(sortedNodes); // need to keep the orientation of the reference way. 100 } 101 102 // Initialize the required parameters. (segment normals, etc.) 103 nodeCount = sortedNodes.size(); 104 pts = new EastNorth[nodeCount]; 105 normals = new EastNorth[nodeCount - 1]; 106 int i = 0; 107 for (Node n : sortedNodes) { 108 EastNorth t = n.getEastNorth(); 109 pts[i] = t; 110 i++; 111 } 112 for (i = 0; i < nodeCount - 1; i++) { 113 double dx = pts[i + 1].getX() - pts[i].getX(); 114 double dy = pts[i + 1].getY() - pts[i].getY(); 115 double len = Math.sqrt(dx * dx + dy * dy); 116 normals[i] = new EastNorth(-dy / len, dx / len); 117 } 118 } 119 120 public boolean isClosedPath() { 121 return sortedNodes.get(0) == sortedNodes.get(sortedNodes.size() - 1); 122 } 123 124 /** 125 * Offsets the way(s) d units. Positive d means to the left (relative to the reference way) 126 * @param d offset 127 */ 128 public void changeOffset(double d) { 129 // This is the core algorithm: 130 /* 1. Calculate a parallel line, offset by 'd', to each segment in the path 131 * 2. Find the intersection of lines belonging to neighboring segments. These become the new node positions 132 * 3. Do some special casing for closed paths 133 * 134 * Simple and probably not even close to optimal performance wise 135 */ 136 137 EastNorth[] ppts = new EastNorth[nodeCount]; 138 139 EastNorth prevA = pts[0].add(normals[0].scale(d)); 140 EastNorth prevB = pts[1].add(normals[0].scale(d)); 141 for (int i = 1; i < nodeCount - 1; i++) { 142 EastNorth a = pts[i].add(normals[i].scale(d)); 143 EastNorth b = pts[i + 1].add(normals[i].scale(d)); 144 if (Geometry.segmentsParallel(a, b, prevA, prevB)) { 145 ppts[i] = a; 146 } else { 147 ppts[i] = Geometry.getLineLineIntersection(a, b, prevA, prevB); 148 } 149 prevA = a; 150 prevB = b; 151 } 152 if (isClosedPath()) { 153 EastNorth a = pts[0].add(normals[0].scale(d)); 154 EastNorth b = pts[1].add(normals[0].scale(d)); 155 if (Geometry.segmentsParallel(a, b, prevA, prevB)) { 156 ppts[0] = a; 157 } else { 158 ppts[0] = Geometry.getLineLineIntersection(a, b, prevA, prevB); 159 } 160 ppts[nodeCount - 1] = ppts[0]; 161 } else { 162 ppts[0] = pts[0].add(normals[0].scale(d)); 163 ppts[nodeCount - 1] = pts[nodeCount - 1].add(normals[nodeCount - 2].scale(d)); 164 } 165 166 for (int i = 0; i < nodeCount; i++) { 167 sortedNodes.get(i).setEastNorth(ppts[i]); 168 } 169 } 170 171 public void commit() { 172 SequenceCommand undoCommand = new SequenceCommand("Make parallel way(s)", makeAddWayAndNodesCommandList()); 173 Main.main.undoRedo.add(undoCommand); 174 } 175 176 private List<Command> makeAddWayAndNodesCommandList() { 177 List<Command> commands = new ArrayList<>(sortedNodes.size() + ways.size()); 178 for (int i = 0; i < sortedNodes.size() - (isClosedPath() ? 1 : 0); i++) { 179 commands.add(new AddCommand(sortedNodes.get(i))); 180 } 181 for (Way w : ways) { 182 commands.add(new AddCommand(w)); 183 } 184 return commands; 185 } 186 187 private static Node copyNode(Node source, boolean copyTags) { 188 if (copyTags) 189 return new Node(source, true); 190 else { 191 Node n = new Node(); 192 n.setCoor(source.getCoor()); 193 return n; 194 } 195 } 196 197 public final List<Way> getWays() { 198 return ways; 199 } 200}