1 | /* Copyright 2013 Malcolm Herring
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2 | *
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3 | * This is free software: you can redistribute it and/or modify
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4 | * it under the terms of the GNU General Public License as published by
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5 | * the Free Software Foundation, version 3 of the License.
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6 | *
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7 | * For a copy of the GNU General Public License, see <http://www.gnu.org/licenses/>.
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8 | */
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9 |
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10 | package s57;
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11 |
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12 | import java.util.*;
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13 |
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14 | import s57.S57att;
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15 | import s57.S57att.*;
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16 | import s57.S57obj;
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17 | import s57.S57obj.*;
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18 | import s57.S57val;
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19 | import s57.S57val.*;
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20 |
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21 | public class S57map {
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22 |
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23 | public enum Nflag {
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24 | ANON, // Edge inner nodes
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25 | ISOL, // Node not part of Edge
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26 | CONN, // Edge first and last nodes
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27 | DPTH // Sounding nodes
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28 | }
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29 |
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30 | public class Snode { // All coordinates in map
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31 | public double lat; // Latitude
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32 | public double lon; // Longitude
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33 | public Nflag flg; // Role of node
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34 |
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35 | public Snode() {
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36 | flg = Nflag.ANON;
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37 | lat = 0;
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38 | lon = 0;
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39 | }
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40 | public Snode(double ilat, double ilon) {
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41 | flg = Nflag.ANON;
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42 | lat = ilat;
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43 | lon = ilon;
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44 | }
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45 | public Snode(double ilat, double ilon, Nflag iflg) {
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46 | lat = ilat;
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47 | lon = ilon;
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48 | flg = iflg;
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49 | }
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50 | }
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51 |
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52 | public class Dnode extends Snode { // All depth soundings
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53 | public double val; // Sounding value
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54 |
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55 | public Dnode() {
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56 | flg = Nflag.DPTH;
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57 | lat = 0;
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58 | lon = 0;
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59 | val = 0;
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60 | }
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61 | public Dnode(double ilat, double ilon, double ival) {
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62 | flg = Nflag.DPTH;
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63 | lat = ilat;
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64 | lon = ilon;
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65 | val = ival;
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66 | }
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67 | }
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68 |
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69 | public class Edge { // A polyline segment
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70 | public long first; // First CONN node
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71 | public long last; // Last CONN node
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72 | public ArrayList<Long> nodes; // Inner ANON nodes
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73 |
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74 | public Edge() {
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75 | first = 0;
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76 | last = 0;
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77 | nodes = new ArrayList<Long>();
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78 | }
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79 | }
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80 |
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81 | public class Side { // An edge as used in a line or area feature
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82 | Edge edge; // Side is formed by this Edge...
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83 | boolean forward; // ... in this direction
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84 |
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85 | public Side(Edge iedge, boolean ifwd) {
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86 | edge = iedge;
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87 | forward = ifwd;
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88 | }
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89 | }
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90 |
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91 | public class Bound { // A single closed area
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92 | public boolean outer; // Role
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93 | ArrayList<Side> sides; // Sides that make up this area
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94 |
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95 | public Bound() {
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96 | outer = true;
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97 | sides = new ArrayList<Side>();
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98 | }
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99 | public Bound(Side iside, boolean irole) {
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100 | outer = irole;
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101 | sides = new ArrayList<Side>();
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102 | sides.add(iside);
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103 | }
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104 | }
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105 |
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106 | public class Area extends ArrayList<Bound> { // The collection of bounds for an area.
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107 | public Area() {
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108 | super();
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109 | }
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110 | }
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111 |
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112 | public class AttItem {
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113 | public Conv conv;
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114 | public Object val;
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115 |
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116 | AttItem(Conv iconv, Object ival) {
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117 | conv = iconv;
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118 | val = ival;
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119 | }
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120 | }
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121 |
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122 | public class AttMap extends EnumMap<Att, AttItem> {
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123 | public AttMap() {
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124 | super(Att.class);
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125 | }
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126 | }
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127 |
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128 | public class ObjTab extends HashMap<Integer, AttMap> {
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129 | public ObjTab() {
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130 | super();
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131 | }
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132 | }
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133 |
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134 | public class ObjMap extends EnumMap<Obj, ObjTab> {
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135 | public ObjMap() {
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136 | super(Obj.class);
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137 | }
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138 | }
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139 |
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140 | public class NodeTab extends HashMap<Long, Snode> {
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141 | public NodeTab() {
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142 | super();
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143 | }
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144 | }
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145 |
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146 | public class EdgeTab extends HashMap<Long, Edge> {
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147 | public EdgeTab() {
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148 | super();
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149 | }
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150 | }
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151 |
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152 | public class AreaTab extends HashMap<Long, Area> {
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153 | public AreaTab() {
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154 | super();
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155 | }
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156 | }
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157 |
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158 | public class FtrMap extends EnumMap<Obj, ArrayList<Feature>> {
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159 | public FtrMap() {
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160 | super(Obj.class);
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161 | }
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162 | }
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163 |
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164 | public class FtrTab extends HashMap<Long, Feature> {
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165 | public FtrTab() {
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166 | super();
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167 | }
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168 | }
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169 |
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170 | public enum Fflag {
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171 | UNKN, POINT, LINE, AREA
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172 | }
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173 |
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174 | public class Feature {
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175 | public Fflag flag;
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176 | public long refs;
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177 | public Obj type;
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178 | public AttMap atts;
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179 | public ObjMap objs;
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180 | public double area;
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181 | public double length;
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182 | public Snode centre;
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183 |
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184 | Feature() {
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185 | flag = Fflag.UNKN;
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186 | refs = 0;
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187 | type = Obj.UNKOBJ;
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188 | atts = new AttMap();
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189 | objs = new ObjMap();
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190 | area = 0;
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191 | length = 0;
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192 | centre = new Snode();
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193 | }
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194 | }
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195 |
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196 | public NodeTab nodes;
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197 | public EdgeTab edges;
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198 | public AreaTab areas;
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199 |
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200 | public FtrMap features;
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201 | public FtrTab index;
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202 |
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203 | private Feature feature;
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204 | private Edge edge;
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205 | private ArrayList<Long> outers;
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206 | private ArrayList<Long> inners;
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207 |
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208 | public class EdgeIterator {
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209 | Edge edge;
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210 | boolean forward;
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211 | ListIterator<Long> it;
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212 |
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213 | public EdgeIterator(Edge iedge, boolean dir) {
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214 | edge = iedge;
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215 | forward = dir;
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216 | it = null;
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217 | }
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218 |
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219 | public boolean hasNext() {
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220 | return (edge != null);
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221 | }
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222 |
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223 | public Snode next() {
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224 | long ref = 0;
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225 | if (forward) {
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226 | if (it == null) {
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227 | ref = edge.first;
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228 | it = edge.nodes.listIterator();
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229 | } else {
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230 | if (it.hasNext()) {
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231 | ref = it.next();
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232 | } else {
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233 | ref = edge.last;
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234 | edge = null;
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235 | }
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236 | }
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237 | } else {
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238 | if (it == null) {
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239 | ref = edge.last;
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240 | it = edge.nodes.listIterator(edge.nodes.size());
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241 | } else {
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242 | if (it.hasPrevious()) {
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243 | ref = it.previous();
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244 | } else {
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245 | ref = edge.first;
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246 | edge = null;
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247 | }
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248 | }
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249 | }
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250 | return nodes.get(ref);
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251 | }
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252 | }
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253 |
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254 | public class BoundIterator {
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255 | Bound bound;
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256 | Side side;
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257 | ListIterator<Side> sit;
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258 | EdgeIterator eit;
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259 |
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260 | public BoundIterator(Bound ibound) {
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261 | bound = ibound;
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262 | sit = bound.sides.listIterator();
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263 | if (sit.hasNext()) {
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264 | side = sit.next();
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265 | eit = new EdgeIterator(side.edge, side.forward);
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266 | } else {
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267 | side = null;
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268 | }
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269 | }
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270 |
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271 | public boolean hasNext() {
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272 | return (side != null) && ((sit.hasNext()) || (eit.hasNext()));
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273 | }
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274 |
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275 | public Snode next() {
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276 | Snode node = null;
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277 | if (side != null) {
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278 | if (eit.hasNext()) {
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279 | node = eit.next();
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280 | } else {
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281 | if (sit.hasNext()) {
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282 | side = sit.next();
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283 | eit = new EdgeIterator(side.edge, side.forward);
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284 | node = eit.next();
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285 | } else {
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286 | side = null;
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287 | }
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288 | }
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289 | }
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290 | return node;
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291 | }
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292 | }
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293 |
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294 | public S57map() {
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295 | nodes = new NodeTab();
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296 | edges = new EdgeTab();
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297 | areas = new AreaTab();
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298 | feature = new Feature();
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299 | features = new FtrMap();
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300 | index = new FtrTab();
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301 | }
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302 |
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303 | public void addNode(long id, double lat, double lon) {
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304 | nodes.put(id, new Snode(Math.toRadians(lat), Math.toRadians(lon)));
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305 | feature = new Feature();
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306 | feature.refs = id;
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307 | feature.flag = Fflag.POINT;
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308 | edge = null;
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309 | }
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310 |
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311 | public void newNode(long id, double lat, double lon, Nflag flag) {
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312 | nodes.put(id, new Snode(Math.toRadians(lat), Math.toRadians(lon), flag));
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313 | if (flag == Nflag.ANON) {
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314 | edge.nodes.add(id);
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315 | }
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316 | }
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317 |
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318 | public void newNode(long id, double lat, double lon, double depth) {
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319 | nodes.put(id, new Dnode(Math.toRadians(lat), Math.toRadians(lon), depth));
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320 | }
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321 |
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322 | public void newEdge(long id) {
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323 | edge = new Edge();
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324 | edges.put(id, edge);
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325 | }
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326 |
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327 | public void addConn(long id, int topi) {
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328 | if (topi == 1) {
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329 | edge.first = id;
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330 | } else {
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331 | edge.last = id;
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332 | }
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333 | }
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334 |
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335 | public void addEdge(long id) {
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336 | feature = new Feature();
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337 | feature.refs = id;
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338 | feature.flag = Fflag.LINE;
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339 | edge = new Edge();
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340 | }
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341 |
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342 | public void addToEdge(long node) {
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343 | if (edge.first == 0) {
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344 | edge.first = node;
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345 | } else {
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346 | if (edge.last != 0) {
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347 | edge.nodes.add(edge.last);
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348 | }
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349 | edge.last = node;
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350 | }
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351 | }
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352 |
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353 | public void addArea(long id) {
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354 | feature = new Feature();
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355 | feature.refs = id;
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356 | feature.flag = Fflag.AREA;
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357 | outers = new ArrayList<Long>();
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358 | inners = new ArrayList<Long>();
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359 | edge = null;
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360 | }
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361 |
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362 | public void addToArea(long id, boolean outer) {
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363 | if (outer) {
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364 | outers.add(id);
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365 | } else {
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366 | inners.add(id);
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367 | }
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368 | }
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369 |
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370 | public void addTag(String key, String val) {
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371 | String subkeys[] = key.split(":");
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372 | if ((subkeys.length > 1) && subkeys[0].equals("seamark")) {
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373 | Obj obj = S57obj.enumType(subkeys[1]);
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374 | if ((subkeys.length > 2) && (obj != Obj.UNKOBJ)) {
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375 | int idx = 0;
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376 | Att att = Att.UNKATT;
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377 | try {
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378 | idx = Integer.parseInt(subkeys[2]);
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379 | if (subkeys.length == 4) {
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380 | att = s57.S57att.enumAttribute(subkeys[3], obj);
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381 | }
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382 | } catch (Exception e) {
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383 | att = S57att.enumAttribute(subkeys[2], obj);
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384 | }
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385 | ObjTab items = feature.objs.get(obj);
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386 | if (items == null) {
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387 | items = new ObjTab();
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388 | feature.objs.put(obj, items);
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389 | }
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390 | AttMap atts = items.get(idx);
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391 | if (atts == null) {
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392 | atts = new AttMap();
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393 | items.put(idx, atts);
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394 | }
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395 | AttVal<?> attval = S57val.convertValue(val, att);
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396 | if (attval.val != null)
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397 | atts.put(att, new AttItem(attval.conv, attval.val));
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398 | } else {
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399 | if (subkeys[1].equals("type")) {
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400 | feature.type = S57obj.enumType(val);
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401 | if (feature.objs.get(feature.type) == null) {
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402 | feature.objs.put(feature.type, new ObjTab());
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403 | }
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404 | } else {
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405 | Att att = S57att.enumAttribute(subkeys[1], Obj.UNKOBJ);
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406 | if (att != Att.UNKATT) {
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407 | AttVal<?> attval = S57val.convertValue(val, att);
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408 | if (attval.val != null)
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409 | feature.atts.put(att, new AttItem(attval.conv, attval.val));
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410 | }
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411 | }
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412 | }
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413 | }
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414 | }
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415 |
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416 | public void tagsDone(long id) {
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417 | switch (feature.flag) {
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418 | case POINT:
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419 | Snode node = nodes.get(id);
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420 | if (node.flg != Nflag.CONN) {
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421 | node.flg = Nflag.ISOL;
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422 | }
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423 | feature.length = 0;
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424 | feature.area = 0;
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425 | break;
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426 | case LINE:
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427 | edges.put(id, edge);
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428 | nodes.get(edge.first).flg = Nflag.CONN;
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429 | nodes.get(edge.last).flg = Nflag.CONN;
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430 | Bound ebound = (new Bound(new Side(edge, true), true));
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431 | feature.length = calcLength(ebound);
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432 | if (edge.first == edge.last) {
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433 | feature.flag = Fflag.AREA;
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434 | Area area = new Area();
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435 | area.add(ebound);
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436 | feature.area = calcArea(ebound);
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437 | areas.put(id, area);
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438 | } else {
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439 | feature.area = 0;
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440 | }
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441 | break;
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442 | case AREA:
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443 | Bound bound = null;
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444 | Area area = new Area();
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445 | ArrayList<Long> role = outers;
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446 | while (role != null) {
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447 | while (!role.isEmpty()) {
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448 | Edge edge = edges.get(role.remove(0));
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449 | long node1 = edge.first;
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450 | long node2 = edge.last;
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451 | bound = new Bound(new Side(edge, true), (role == outers));
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452 | if (node1 != node2) {
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453 | for (ListIterator<Long> it = role.listIterator(0); it.hasNext();) {
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454 | Edge nedge = edges.get(it.next());
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455 | if (nedge.first == node2) {
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456 | bound.sides.add(new Side(nedge, true));
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457 | it.remove();
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458 | if (nedge.last == node2)
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459 | break;
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460 | } else if (nedge.last == node2) {
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461 | bound.sides.add(new Side(nedge, false));
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462 | it.remove();
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463 | if (nedge.first == node2)
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464 | break;
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465 | }
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466 | }
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467 | }
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468 | area.add(bound);
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469 | }
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470 | if (role == outers) {
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471 | feature.length = calcLength(bound);
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472 | feature.area = calcArea(bound);
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473 | role = inners;
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474 | } else {
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475 | role = null;
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476 | }
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477 | }
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478 | areas.put(id, area);
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479 | break;
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480 | case UNKN:
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481 | default:
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482 | break;
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483 | }
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484 | if ((feature.type != Obj.UNKOBJ) && !((edge != null) && (edge.last == 0))) {
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485 | index.put(id, feature);
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486 | if (features.get(feature.type) == null) {
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487 | features.put(feature.type, new ArrayList<Feature>());
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488 | }
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489 | feature.centre = findCentroid(feature);
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490 | features.get(feature.type).add(feature);
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491 | }
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492 | }
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493 |
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494 | double signedArea(Bound bound) {
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495 | Snode node;
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496 | double lat, lon, llon, llat;
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497 | lat = lon = llon = llat = 0;
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498 | double sigma = 0;
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499 | BoundIterator it = new BoundIterator(bound);
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500 | while (it.hasNext()) {
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501 | llon = lon;
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502 | llat = lat;
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503 | node = it.next();
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504 | lat = node.lat;
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505 | lon = node.lon;
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506 | sigma += (lon * Math.sin(llat)) - (llon * Math.sin(lat));
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507 | }
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508 | return sigma / 2.0;
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509 | }
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510 |
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511 | public boolean handOfArea(Bound bound) {
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512 | return (signedArea(bound) < 0);
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513 | }
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514 |
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515 | public double calcArea(Bound bound) {
|
---|
516 | return Math.abs(signedArea(bound)) * 3444 * 3444;
|
---|
517 | }
|
---|
518 |
|
---|
519 | public double calcLength(Bound bound) {
|
---|
520 | Snode node;
|
---|
521 | double lat, lon, llon, llat;
|
---|
522 | lat = lon = llon = llat = 0;
|
---|
523 | double sigma = 0;
|
---|
524 | BoundIterator it = new BoundIterator(bound);
|
---|
525 | if (it.hasNext()) {
|
---|
526 | node = it.next();
|
---|
527 | lat = node.lat;
|
---|
528 | lon = node.lon;
|
---|
529 | while (it.hasNext()) {
|
---|
530 | llon = lon;
|
---|
531 | llat = lat;
|
---|
532 | node = it.next();
|
---|
533 | lat = node.lat;
|
---|
534 | lon = node.lon;
|
---|
535 | sigma += Math.acos(Math.sin(lat) * Math.sin(llat) + Math.cos(lat) * Math.cos(llat) * Math.cos(llon - lon));
|
---|
536 | }
|
---|
537 | }
|
---|
538 | return sigma * 3444;
|
---|
539 | }
|
---|
540 |
|
---|
541 | public Snode findCentroid(Feature feature) {
|
---|
542 | double lat, lon, slat, slon, llat, llon;
|
---|
543 | llat = llon = lat = lon = slat = slon = 0;
|
---|
544 | double sarc = 0;
|
---|
545 | boolean first = true;
|
---|
546 | switch (feature.flag) {
|
---|
547 | case POINT:
|
---|
548 | return nodes.get(feature.refs);
|
---|
549 | case LINE:
|
---|
550 | Edge edge = edges.get(feature.refs);
|
---|
551 | EdgeIterator eit = new EdgeIterator(edge, true);
|
---|
552 | while (eit.hasNext()) {
|
---|
553 | Snode node = eit.next();
|
---|
554 | lat = node.lat;
|
---|
555 | lon = node.lon;
|
---|
556 | if (first) {
|
---|
557 | first = false;
|
---|
558 | } else {
|
---|
559 | sarc += (Math.acos(Math.cos(lon - llon) * Math.cos(lat - llat)));
|
---|
560 | }
|
---|
561 | llat = lat;
|
---|
562 | llon = lon;
|
---|
563 | }
|
---|
564 | double harc = sarc / 2;
|
---|
565 | sarc = 0;
|
---|
566 | first = true;
|
---|
567 | eit = new EdgeIterator(edge, true);
|
---|
568 | while (eit.hasNext()) {
|
---|
569 | Snode node = eit.next();
|
---|
570 | lat = node.lat;
|
---|
571 | lon = node.lon;
|
---|
572 | if (first) {
|
---|
573 | first = false;
|
---|
574 | } else {
|
---|
575 | sarc = (Math.acos(Math.cos(lon - llon) * Math.cos(lat - llat)));
|
---|
576 | if (sarc > harc)
|
---|
577 | break;
|
---|
578 | }
|
---|
579 | harc -= sarc;
|
---|
580 | llat = lat;
|
---|
581 | llon = lon;
|
---|
582 | }
|
---|
583 | return new Snode(llat + ((lat - llat) * harc / sarc), llon + ((lon - llon) * harc / sarc));
|
---|
584 | case AREA:
|
---|
585 | Bound bound = areas.get(feature.refs).get(0);
|
---|
586 | BoundIterator bit = new BoundIterator(bound);
|
---|
587 | while (bit.hasNext()) {
|
---|
588 | Snode node = bit.next();
|
---|
589 | lat = node.lat;
|
---|
590 | lon = node.lon;
|
---|
591 | if (first) {
|
---|
592 | first = false;
|
---|
593 | } else {
|
---|
594 | double arc = (Math.acos(Math.cos(lon - llon) * Math.cos(lat - llat)));
|
---|
595 | slat += ((lat + llat) / 2 * arc);
|
---|
596 | slon += ((lon + llon) / 2 * arc);
|
---|
597 | sarc += arc;
|
---|
598 | }
|
---|
599 | llon = lon;
|
---|
600 | llat = lat;
|
---|
601 | }
|
---|
602 | return new Snode((sarc > 0.0 ? slat / sarc : 0.0), (sarc > 0.0 ? slon / sarc : 0.0));
|
---|
603 | default:
|
---|
604 | }
|
---|
605 | return null;
|
---|
606 | }
|
---|
607 |
|
---|
608 | }
|
---|