private void processBlocks(
IMapDatabaseCallback mapDatabaseCallback,
QueryParameters queryParameters,
SubFileParameter subFileParameter)
throws IOException {
boolean queryIsWater = true;
// boolean queryReadWaterInfo = false;
// read and process all blocks from top to bottom and from left to right
for (long row = queryParameters.fromBlockY; row <= queryParameters.toBlockY; ++row) {
for (long column = queryParameters.fromBlockX; column <= queryParameters.toBlockX; ++column) {
// calculate the actual block number of the needed block in the
// file
long blockNumber = row * subFileParameter.blocksWidth + column;
// get the current index entry
long currentBlockIndexEntry =
sDatabaseIndexCache.getIndexEntry(subFileParameter, blockNumber);
// check if the current query would still return a water tile
if (queryIsWater) {
// check the water flag of the current block in its index
// entry
queryIsWater &= (currentBlockIndexEntry & BITMASK_INDEX_WATER) != 0;
// queryReadWaterInfo = true;
}
// get and check the current block pointer
long currentBlockPointer = currentBlockIndexEntry & BITMASK_INDEX_OFFSET;
if (currentBlockPointer < 1 || currentBlockPointer > subFileParameter.subFileSize) {
LOG.warning("invalid current block pointer: " + currentBlockPointer);
LOG.warning("subFileSize: " + subFileParameter.subFileSize);
return;
}
long nextBlockPointer;
// check if the current block is the last block in the file
if (blockNumber + 1 == subFileParameter.numberOfBlocks) {
// set the next block pointer to the end of the file
nextBlockPointer = subFileParameter.subFileSize;
} else {
// get and check the next block pointer
nextBlockPointer =
sDatabaseIndexCache.getIndexEntry(subFileParameter, blockNumber + 1)
& BITMASK_INDEX_OFFSET;
if (nextBlockPointer < 1 || nextBlockPointer > subFileParameter.subFileSize) {
LOG.warning("invalid next block pointer: " + nextBlockPointer);
LOG.warning("sub-file size: " + subFileParameter.subFileSize);
return;
}
}
// calculate the size of the current block
int currentBlockSize = (int) (nextBlockPointer - currentBlockPointer);
if (currentBlockSize < 0) {
LOG.warning("current block size must not be negative: " + currentBlockSize);
return;
} else if (currentBlockSize == 0) {
// the current block is empty, continue with the next block
continue;
} else if (currentBlockSize > ReadBuffer.MAXIMUM_BUFFER_SIZE) {
// the current block is too large, continue with the next
// block
LOG.warning("current block size too large: " + currentBlockSize);
continue;
} else if (currentBlockPointer + currentBlockSize > mFileSize) {
LOG.warning("current block largher than file size: " + currentBlockSize);
return;
}
// seek to the current block in the map file
mInputFile.seek(subFileParameter.startAddress + currentBlockPointer);
// read the current block into the buffer
if (!mReadBuffer.readFromFile(currentBlockSize)) {
// skip the current block
LOG.warning("reading current block has failed: " + currentBlockSize);
return;
}
// calculate the top-left coordinates of the underlying tile
double tileLatitudeDeg =
MercatorProjection.tileYToLatitude(
subFileParameter.boundaryTileTop + row, subFileParameter.baseZoomLevel);
double tileLongitudeDeg =
MercatorProjection.tileXToLongitude(
subFileParameter.boundaryTileLeft + column, subFileParameter.baseZoomLevel);
mTileLatitude = (int) (tileLatitudeDeg * 1000000);
mTileLongitude = (int) (tileLongitudeDeg * 1000000);
try {
processBlock(queryParameters, subFileParameter, mapDatabaseCallback);
} catch (ArrayIndexOutOfBoundsException e) {
LOG.log(Level.SEVERE, null, e);
}
}
}
// the query is finished, was the water flag set for all blocks?
// if (queryIsWater && queryReadWaterInfo) {
// Tag[] tags = new Tag[1];
// tags[0] = TAG_NATURAL_WATER;
//
// System.arraycopy(WATER_TILE_COORDINATES, 0, mWayNodes,
// mWayNodePosition, 8);
// mWayNodePosition += 8;
// mapDatabaseCallback.renderWaterBackground(tags, wayDataContainer);
// }
}
