src/tim/prune/function/srtm/LookupSrtmFunction.java

   1 package tim.prune.function.srtm;
   2
   3 import java.util.ArrayList;
   4
   5 import javax.swing.JOptionPane;
   6
   7 import tim.prune.App;
   8 import tim.prune.DataSubscriber;
   9 import tim.prune.GenericFunction;
  10 import tim.prune.I18nManager;
  11 import tim.prune.UpdateMessageBroker;
  12 import tim.prune.data.Altitude;
  13 import tim.prune.data.DataPoint;
  14 import tim.prune.data.Field;
  15 import tim.prune.data.Track;
  16 import tim.prune.data.UnitSetLibrary;
  17 import tim.prune.gui.ProgressDialog;
  18 import tim.prune.undo.UndoLookupSrtm;
  19
  20 /**
  21  * Class to provide a lookup function for point altitudes using the Space
  22  * Shuttle's SRTM data files. HGT files are downloaded into memory via HTTP and
  23  * point altitudes can then be interpolated from the 3m grid data.
  24  */
  25 public class LookupSrtmFunction extends GenericFunction implements Runnable
  26 {
  27         /** Progress dialog */
  28         private ProgressDialog _progress = null;
  29         /** Track to process */
  30         private Track _track = null;
  31         /** Flag for whether this is a real track or a terrain one */
  32         private boolean _normalTrack = true;
  33         /** Flag to check whether this function is currently running or not */
  34         private boolean _running = false;
  35
  36         /** Altitude below which is considered void */
  37         private static final int VOID_VAL = -32768;
  38
  39         /**
  40          * Constructor
  41          * @param inApp  App object
  42          */
  43         public LookupSrtmFunction(App inApp) {
  44                 super(inApp);
  45         }
  46
  47         /** @return name key */
  48         public String getNameKey() {
  49                 return "function.lookupsrtm";
  50         }
  51
  52         /**
  53          * Begin the lookup using the normal track
  54          */
  55         public void begin() {
  56                 begin(_app.getTrackInfo().getTrack(), true);
  57         }
  58
  59         /**
  60          * Begin the lookup with an alternative track
  61          * @param inAlternativeTrack
  62          */
  63         public void begin(Track inAlternativeTrack) {
  64                 begin(inAlternativeTrack, false);
  65         }
  66
  67         /**
  68          * Begin the function with the given parameters
  69          * @param inTrack track to process
  70          * @param inNormalTrack true if this is a "normal" track, false for an artificially constructed one such as for terrain
  71          */
  72         private void begin(Track inTrack, boolean inNormalTrack)
  73         {
  74                 _running = true;
  75                 if (! SrtmDiskCache.ensureCacheIsUsable())
  76                 {
  77                         _app.showErrorMessage(getNameKey(), "error.cache.notthere");
  78                 }
  79                 if (_progress == null) {
  80                         _progress = new ProgressDialog(_parentFrame, getNameKey());
  81                 }
  82                 _progress.show();
  83                 _track = inTrack;
  84                 _normalTrack = inNormalTrack;
  85                 // start new thread for time-consuming part
  86                 new Thread(this).start();
  87         }
  88
  89         /**
  90          * Run method using separate thread
  91          */
  92         public void run()
  93         {
  94                 // Compile list of tiles to get
  95                 ArrayList<SrtmTile> tileList = new ArrayList<SrtmTile>();
  96                 boolean hasZeroAltitudePoints = false;
  97                 boolean hasNonZeroAltitudePoints = false;
  98                 // First, loop to see what kind of points we have
  99                 for (int i = 0; i < _track.getNumPoints(); i++)
 100                 {
 101                         if (_track.getPoint(i).hasAltitude())
 102                         {
 103                                 if (_track.getPoint(i).getAltitude().getValue() == 0) {
 104                                         hasZeroAltitudePoints = true;
 105                                 }
 106                                 else {
 107                                         hasNonZeroAltitudePoints = true;
 108                                 }
 109                         }
 110                 }
 111                 // Should we overwrite the zero altitude values?
 112                 boolean overwriteZeros = hasZeroAltitudePoints && !hasNonZeroAltitudePoints;
 113                 // If non-zero values present as well, ask user whether to overwrite the zeros or not
 114                 if (hasNonZeroAltitudePoints && hasZeroAltitudePoints && JOptionPane.showConfirmDialog(_parentFrame,
 115                         I18nManager.getText("dialog.lookupsrtm.overwritezeros"), I18nManager.getText(getNameKey()),
 116                         JOptionPane.YES_NO_OPTION) == JOptionPane.YES_OPTION)
 117                 {
 118                         overwriteZeros = true;
 119                 }
 120
 121                 // Now loop again to extract the required tiles
 122                 for (int i = 0; i < _track.getNumPoints(); i++)
 123                 {
 124                         // Consider points which don't have altitudes or have zero values
 125                         if (needsAltitude(_track.getPoint(i), overwriteZeros))
 126                         {
 127                                 SrtmTile tile = new SrtmTile(_track.getPoint(i));
 128                                 boolean alreadyGot = false;
 129                                 for (int t = 0; t < tileList.size(); t++)
 130                                 {
 131                                         if (tileList.get(t).equals(tile)) {
 132                                                 alreadyGot = true;
 133                                         }
 134                                 }
 135                                 if (!alreadyGot) {tileList.add(tile);}
 136                         }
 137                 }
 138                 lookupValues(tileList, overwriteZeros);
 139                 // Finished
 140                 _running = false;
 141         }
 142
 143         /**
 144          * true if we need to set the altitude of this point
 145          */
 146         private boolean needsAltitude(DataPoint point, boolean overwriteZeros)
 147         {
 148                 if (!point.hasAltitude())
 149                 {
 150                         return true;
 151                 }
 152                 if (overwriteZeros && point.getAltitude().getValue() == 0)
 153                 {
 154                         return true;
 155                 }
 156                 return false;
 157         }
 158
 159         /**
 160          * Lookup the values from SRTM data
 161          * @param inTileList list of tiles to get
 162          * @param inOverwriteZeros true to overwrite zero altitude values
 163          */
 164         private void lookupValues(ArrayList<SrtmTile> inTileList, boolean inOverwriteZeros)
 165         {
 166                 UndoLookupSrtm undo = new UndoLookupSrtm(_app.getTrackInfo());
 167                 int numAltitudesFound = 0;
 168                 // Update progress bar
 169                 if (_progress != null)
 170                 {
 171                         _progress.setMaximum(inTileList.size());
 172                         _progress.setValue(0);
 173                 }
 174                 String errorMessage = "";
 175                 for (int t=0; t<inTileList.size() && !_progress.isCancelled(); t++)
 176                 {
 177                         SrtmTile tile = inTileList.get(t);
 178                         SrtmSource srtmSource = tile.findBestCachedSource();
 179
 180                         if (srtmSource == null)
 181                         {
 182                                 errorMessage += "Tile "+tile.getTileName()+" not in cache!\n";
 183                                 continue;
 184                         }
 185
 186                         // Set progress
 187                         _progress.setValue(t);
 188
 189                         int[] heights;
 190                         try {
 191                                 heights = srtmSource.getTileHeights(tile);
 192                         }
 193                         catch (SrtmSourceException e)
 194                         {
 195                                 errorMessage += e.getMessage();
 196                                 e.printStackTrace();
 197                                 continue;
 198                         }
 199                         int rowSize = srtmSource.getRowSize(tile);
 200                         if (rowSize <= 0)
 201                         {
 202                                 errorMessage += "Tile "+tile.getTileName()+" is corrupted";
 203                         }
 204
 205                         // Loop over all points in track, try to apply altitude from array
 206                         for (int p = 0; p < _track.getNumPoints(); p++)
 207                         {
 208                                 DataPoint point = _track.getPoint(p);
 209                                 if (needsAltitude(point, inOverwriteZeros))
 210                                 {
 211                                         if (new SrtmTile(point).equals(tile))
 212                                         {
 213                                                 double x = (point.getLongitude().getDouble() - tile.getLongitude()) * (rowSize - 1);
 214                                                 double y = rowSize - (point.getLatitude().getDouble() - tile.getLatitude()) * (rowSize - 1);
 215                                                 int idx1 = ((int)y)*rowSize + (int)x;
 216                                                 try
 217                                                 {
 218                                                         int[] fouralts = {heights[idx1], heights[idx1+1], heights[idx1-rowSize], heights[idx1-rowSize+1]};
 219                                                         int numVoids = (fouralts[0]==VOID_VAL?1:0) + (fouralts[1]==VOID_VAL?1:0)
 220                                                                 + (fouralts[2]==VOID_VAL?1:0) + (fouralts[3]==VOID_VAL?1:0);
 221                                                         // if (numVoids > 0) System.out.println(numVoids + " voids found");
 222                                                         double altitude = 0.0;
 223                                                         switch (numVoids)
 224                                                         {
 225                                                         case 0: altitude = bilinearInterpolate(fouralts, x, y); break;
 226                                                         case 1: altitude = bilinearInterpolate(fixVoid(fouralts), x, y); break;
 227                                                         case 2:
 228                                                         case 3: altitude = averageNonVoid(fouralts); break;
 229                                                         default: altitude = VOID_VAL;
 230                                                         }
 231                                                         // Special case for terrain tracks, don't interpolate voids yet
 232                                                         if (!_normalTrack && numVoids > 0) {
 233                                                                 altitude = VOID_VAL;
 234                                                         }
 235                                                         if (altitude != VOID_VAL)
 236                                                         {
 237                                                                 point.setFieldValue(Field.ALTITUDE, ""+altitude, false);
 238                                                                 // depending on settings, this value may have been added as feet, we need to force metres
 239                                                                 point.getAltitude().reset(new Altitude((int)altitude, UnitSetLibrary.UNITS_METRES));
 240                                                                 numAltitudesFound++;
 241                                                         }
 242                                                 }
 243                                                 catch (ArrayIndexOutOfBoundsException obe) {
 244                                                         errorMessage += "Point not in tile? lat=" + point.getLatitude().getDouble() + ", x=" + x + ", y=" + y + ", idx=" + idx1+"\n";
 245                                                 }
 246                                         }
 247                                 }
 248                         }
 249                 }
 250
 251                 _progress.dispose();
 252                 if (_progress.isCancelled()) {
 253                         return;
 254                 }
 255
 256                 if (! errorMessage.equals("")) {
 257                         _app.showErrorMessageNoLookup(getNameKey(), errorMessage);
 258                         return;
 259                 }
 260                 if (numAltitudesFound > 0)
 261                 {
 262                         // Inform app including undo information
 263                         _track.requestRescale();
 264                         UpdateMessageBroker.informSubscribers(DataSubscriber.DATA_ADDED_OR_REMOVED);
 265                         // Don't update app if we're doing another track
 266                         if (_normalTrack)
 267                         {
 268                                 _app.completeFunction(undo,
 269                                         I18nManager.getTextWithNumber("confirm.lookupsrtm", numAltitudesFound));
 270                         }
 271                 }
 272                 else if (inTileList.size() > 0) {
 273                         _app.showErrorMessage(getNameKey(), "error.lookupsrtm.nonefound");
 274                 }
 275                 else {
 276                         _app.showErrorMessage(getNameKey(), "error.lookupsrtm.nonerequired");
 277                 }
 278         }
 279
 280         /**
 281          * Perform a bilinear interpolation on the given altitude array
 282          * @param inAltitudes array of four altitude values on corners of square (bl, br, tl, tr)
 283          * @param inX x coordinate
 284          * @param inY y coordinate
 285          * @return interpolated altitude
 286          */
 287         private static double bilinearInterpolate(int[] inAltitudes, double inX, double inY)
 288         {
 289                 double alpha = inX - (int) inX;
 290                 double beta  = 1 - (inY - (int) inY);
 291                 double alt = (1-alpha)*(1-beta)*inAltitudes[0] + alpha*(1-beta)*inAltitudes[1]
 292                         + (1-alpha)*beta*inAltitudes[2] + alpha*beta*inAltitudes[3];
 293                 return alt;
 294         }
 295
 296         /**
 297          * Fix a single void in the given array by replacing it with the average of the others
 298          * @param inAltitudes array of altitudes containing one void
 299          * @return fixed array without voids
 300          */
 301         private static int[] fixVoid(int[] inAltitudes)
 302         {
 303                 int[] fixed = new int[inAltitudes.length];
 304                 for (int i = 0; i < inAltitudes.length; i++)
 305                 {
 306                         if (inAltitudes[i] == VOID_VAL) {
 307                                 fixed[i] = (int) Math.round(averageNonVoid(inAltitudes));
 308                         }
 309                         else {
 310                                 fixed[i] = inAltitudes[i];
 311                         }
 312                 }
 313                 return fixed;
 314         }
 315
 316         /**
 317          * Calculate the average of the non-void altitudes in the given array
 318          * @param inAltitudes array of altitudes with one or more voids
 319          * @return average of non-void altitudes
 320          */
 321         private static final double averageNonVoid(int[] inAltitudes)
 322         {
 323                 double totalAltitude = 0.0;
 324                 int numAlts = 0;
 325                 for (int i = 0; i < inAltitudes.length; i++)
 326                 {
 327                         if (inAltitudes[i] != VOID_VAL)
 328                         {
 329                                 totalAltitude += inAltitudes[i];
 330                                 numAlts++;
 331                         }
 332                 }
 333                 if (numAlts < 1) {return VOID_VAL;}
 334                 return totalAltitude / numAlts;
 335         }
 336
 337         /**
 338          * @return true if a thread is currently running
 339          */
 340         public boolean isRunning()
 341         {
 342                 return _running;
 343         }
 344 }