public RequestedTileInformation GetTileInformation(long x, long y, int zoom)
{
RequestedTileInformation ti = new RequestedTileInformation();
try
{
ti.mapFile = _mapFile;
ti.X = x;
ti.Y = y;
ti.Zoom = zoom;
ti.ZoomIntervalConfig = this.ZoomIntervalConfig;
if (zoom < ZoomIntervalConfig.BaseZoomLevel)
{
// calculate the XY numbers of the upper left and lower right sub-tiles
int zoomLevelDifference = ZoomIntervalConfig.BaseZoomLevel - zoom;
ti.FromBaseTileX = x << zoomLevelDifference;
ti.FromBaseTileY = y << zoomLevelDifference;
ti.ToBaseTileX = ti.FromBaseTileX + (1 << zoomLevelDifference) - 1;
ti.ToBaseTileY = ti.FromBaseTileY + (1 << zoomLevelDifference) - 1;
ti.UseSubTileBitmapMask = false;
}
else if (zoom > ZoomIntervalConfig.BaseZoomLevel)
{
// calculate the XY numbers of the parent base tile
int zoomLevelDifference = zoom - ZoomIntervalConfig.BaseZoomLevel;
ti.FromBaseTileX = x >> zoomLevelDifference;
ti.FromBaseTileY = y >> zoomLevelDifference;
ti.ToBaseTileX = ti.FromBaseTileX;
ti.ToBaseTileY = ti.FromBaseTileY;
ti.UseSubTileBitmapMask = true;
//calculate ti.SubTileBitmapMask
if (zoomLevelDifference == 1)
{
if (x % 2 == 0 && y % 2 == 0)
{
// upper left quadrant
ti.SubTileBitmapMask = 0xcc00;
}
else if (x % 2 == 1 && y % 2 == 0)
{
// upper right quadrant
ti.SubTileBitmapMask = 0x3300;
}
else if (x % 2 == 0 && y % 2 == 1)
{
// lower left quadrant
ti.SubTileBitmapMask = 0xcc;
}
else
{
// lower right quadrant
ti.SubTileBitmapMask = 0x33;
}
}
else
{
// calculate the XY numbers of the second level sub-tile
long subtileX = x >> (zoomLevelDifference - 2);
long subtileY = y >> (zoomLevelDifference - 2);
// calculate the XY numbers of the parent tile
long parentTileX = subtileX >> 1;
long parentTileY = subtileY >> 1;
// determine the correct bitmask for all 16 sub-tiles
if (parentTileX % 2 == 0 && parentTileY % 2 == 0)
{
if (subtileX % 2 == 0 && subtileY % 2 == 0)
{
// upper left sub-tile
ti.SubTileBitmapMask = 0x8000;
}
else if (subtileX % 2 == 1 && subtileY % 2 == 0)
{
// upper right sub-tile
ti.SubTileBitmapMask = 0x4000;
}
else if (subtileX % 2 == 0 && subtileY % 2 == 1)
{
// lower left sub-tile
ti.SubTileBitmapMask = 0x800;
}
else
{
// lower right sub-tile
ti.SubTileBitmapMask = 0x400;
}
}
else if (parentTileX % 2 == 1 && parentTileY % 2 == 0)
{
if (subtileX % 2 == 0 && subtileY % 2 == 0)
{
// upper left sub-tile
ti.SubTileBitmapMask = 0x2000;
}
else if (subtileX % 2 == 1 && subtileY % 2 == 0)
{
// upper right sub-tile
ti.SubTileBitmapMask = 0x1000;
}
else if (subtileX % 2 == 0 && subtileY % 2 == 1)
{
// lower left sub-tile
ti.SubTileBitmapMask = 0x200;
}
else
{
// lower right sub-tile
ti.SubTileBitmapMask = 0x100;
}
}
else if (parentTileX % 2 == 0 && parentTileY % 2 == 1)
{
if (subtileX % 2 == 0 && subtileY % 2 == 0)
{
// upper left sub-tile
ti.SubTileBitmapMask = 0x80;
}
else if (subtileX % 2 == 1 && subtileY % 2 == 0)
{
// upper right sub-tile
ti.SubTileBitmapMask = 0x40;
}
else if (subtileX % 2 == 0 && subtileY % 2 == 1)
{
// lower left sub-tile
ti.SubTileBitmapMask = 0x8;
}
else
{
// lower right sub-tile
ti.SubTileBitmapMask = 0x4;
}
}
else
{
if (subtileX % 2 == 0 && subtileY % 2 == 0)
{
// upper left sub-tile
ti.SubTileBitmapMask = 0x20;
}
else if (subtileX % 2 == 1 && subtileY % 2 == 0)
{
// upper right sub-tile
ti.SubTileBitmapMask = 0x10;
}
else if (subtileX % 2 == 0 && subtileY % 2 == 1)
{
// lower left sub-tile
ti.SubTileBitmapMask = 0x2;
}
else
{
// lower right sub-tile
ti.SubTileBitmapMask = 0x1;
}
}
}
}
else
{
// use the tile XY numbers of the requested tile
ti.FromBaseTileX = x;
ti.FromBaseTileY = y;
ti.ToBaseTileX = ti.FromBaseTileX;
ti.ToBaseTileY = ti.FromBaseTileY;
ti.UseSubTileBitmapMask = false;
}
ti.FromBlockX = Math.Max(ti.FromBaseTileX - MinX, 0);
ti.FromBlockY = Math.Max(ti.FromBaseTileY - MinY, 0);
ti.ToBlockX = Math.Min(ti.ToBaseTileX - MinX, MaxX);
ti.ToBlockY = Math.Min(ti.ToBaseTileY - MinY, MaxY);
ti.POIs = new List <POI>();
ti.Ways = new List <Way>();
for (long row = ti.FromBlockY; row <= ti.ToBlockY; row++)
{
for (long column = ti.FromBlockX; column <= ti.ToBlockX; column++)
{
// calculate the actual block number of the needed block in the file
long blockNumber = (row * (MaxX - MinX + 1)) + column;
if (blockNumber >= _tileAbsOffsets.Length || _tileAbsOffsets[blockNumber] == 0 || _tileAbsOffsets[blockNumber] >= ZoomIntervalConfig.SubFileSize)
{
continue;
}
long blockSize;
if (blockNumber < _tileAbsOffsets.Length - 1)
{
blockSize = _tileAbsOffsets[blockNumber + 1] - _tileAbsOffsets[blockNumber];
}
else
{
blockSize = ZoomIntervalConfig.SubFileSize - _tileAbsOffsets[blockNumber] + 1;
}
if (blockSize < 1)
{
continue;
}
ti.TileDataBuffer = new byte[blockSize];
_mapFile.ReadBuffer(ti.TileDataBuffer, _tileAbsOffsets[blockNumber] + ZoomIntervalConfig.AbsStartPositionSubFile, (int)blockSize);
using (ti.TileDataBufferStream = new System.IO.MemoryStream(ti.TileDataBuffer))
{
// calculate the top-left coordinates of the underlying tile
ti.TileLatitudeDeg = MapFile.GetLatitude(MinY + row, ZoomIntervalConfig.BaseZoomLevel);
ti.TileLongitudeDeg = MapFile.GetLongitude(MinX + column, ZoomIntervalConfig.BaseZoomLevel);
ti.TileLatitude = (int)(ti.TileLatitudeDeg * 1000000);
ti.TileLongitude = (int)(ti.TileLongitudeDeg * 1000000);
if (_mapFile.Header.DebugInformationPresent)
{
ti.TileDataBufferStream.Position = 32;
}
//get the zoom table
int rows = ZoomIntervalConfig.MaxZoomLevel - ZoomIntervalConfig.MinZoomLevel + 1;
ti.ZoomTable = new int[rows, 2];
int cumulatedNumberOfPois = 0;
int cumulatedNumberOfWays = 0;
for (int r = 0; r < rows; r++)
{
cumulatedNumberOfPois += (int)MapFile.ReadVBEUint(ti.TileDataBufferStream);
cumulatedNumberOfWays += (int)MapFile.ReadVBEUint(ti.TileDataBufferStream);
ti.ZoomTable[r, 0] = cumulatedNumberOfPois;
ti.ZoomTable[r, 1] = cumulatedNumberOfWays;
}
ti.ZoomTableRow = zoom - ZoomIntervalConfig.MinZoomLevel;
ti.PoisOnQueryZoomLevel = ti.ZoomTable[ti.ZoomTableRow, 0];
ti.WaysOnQueryZoomLevel = ti.ZoomTable[ti.ZoomTableRow, 1];
ti.FirstWayOffset = MapFile.ReadVBEUint(ti.TileDataBufferStream);
ti.FirstWayOffset += ti.TileDataBufferStream.Position;
//get POIs
for (int p = 0; p < ti.PoisOnQueryZoomLevel; p++)
{
POI poi = new POI();
if (_mapFile.Header.DebugInformationPresent)
{
ti.TileDataBufferStream.Position += 32;
}
//lat/lon
poi.Latitude = ti.TileLatitude + MapFile.ReadVBESint(ti.TileDataBufferStream);
poi.Longitude = ti.TileLongitude + MapFile.ReadVBESint(ti.TileDataBufferStream);
//layer and tag ids
poi.TagIDs = new List <int>();
byte b = (byte)ti.TileDataBufferStream.ReadByte();
poi.Layer = b >> 4;
int tagCount = (b & 0x0F);
for (int t = 0; t < tagCount; t++)
{
poi.TagIDs.Add((int)MapFile.ReadVBEUint(ti.TileDataBufferStream));
}
//flags
b = (byte)ti.TileDataBufferStream.ReadByte();
if ((b & 0x80) == 0x80)
{
poi.Name = MapFile.ReadUTF8EncodedString(ti.TileDataBufferStream);
}
else
{
poi.Name = null;
}
if ((b & 0x40) == 0x40)
{
poi.HouseNumber = MapFile.ReadUTF8EncodedString(ti.TileDataBufferStream);
}
else
{
poi.HouseNumber = null;
}
if ((b & 0x20) == 0x20)
{
poi.Elevation = MapFile.ReadVBESint(ti.TileDataBufferStream);
}
else
{
poi.Elevation = null;
}
ti.POIs.Add(poi);
}
ti.TileDataBufferStream.Position = ti.FirstWayOffset;
//get ways
for (int w = 0; w < ti.WaysOnQueryZoomLevel; w++)
{
Way way = new Way();
if (_mapFile.Header.DebugInformationPresent)
{
ti.TileDataBufferStream.Position += 32;
}
int wayDataSize = (int)MapFile.ReadVBEUint(ti.TileDataBufferStream);
int subTileBitmap = MapFile.ReadUInt16(ti.TileDataBufferStream);
if (ti.UseSubTileBitmapMask)
{
// check if the way is inside the requested tile
if ((ti.SubTileBitmapMask & subTileBitmap) == 0)
{
// skip the rest of the way and continue with the next way
ti.TileDataBufferStream.Position += (wayDataSize - 2);
continue;
}
}
//layer and tags
way.TagIDs = new List <int>();
byte b = (byte)ti.TileDataBufferStream.ReadByte();
way.Layer = b >> 4;
int tagCount = (b & 0x0F);
for (int t = 0; t < tagCount; t++)
{
way.TagIDs.Add((int)MapFile.ReadVBEUint(ti.TileDataBufferStream));
}
//feature bytes
b = (byte)ti.TileDataBufferStream.ReadByte();
if ((b & 0x80) == 0x80)
{
way.Name = MapFile.ReadUTF8EncodedString(ti.TileDataBufferStream);
}
else
{
way.Name = null;
}
if ((b & 0x40) == 0x40)
{
way.HouseNumber = MapFile.ReadUTF8EncodedString(ti.TileDataBufferStream);
}
else
{
way.HouseNumber = null;
}
if ((b & 0x20) == 0x20)
{
way.Reference = MapFile.ReadUTF8EncodedString(ti.TileDataBufferStream);
}
else
{
way.Reference = null;
}
if ((b & 0x10) == 0x10)
{
way.LabelLatitude = ti.TileLatitude + MapFile.ReadVBESint(ti.TileDataBufferStream);
way.LabelLongitude = ti.TileLongitude + MapFile.ReadVBESint(ti.TileDataBufferStream);
}
else
{
way.LabelLatitude = null;
way.LabelLongitude = null;
}
int numberOfBlocks;
if ((b & 0x08) == 0x08)
{
numberOfBlocks = (int)MapFile.ReadVBEUint(ti.TileDataBufferStream);
}
else
{
numberOfBlocks = 1;
}
bool doubleEncoding = ((b & 0x04) == 0x04);
way.WayDataBlocks = new List <Way.WayData>();
for (int wb = 0; wb < numberOfBlocks; wb++)
{
//read: way data
Way.WayData wd = new Way.WayData();
int numberOfWayCoordBlocks = (int)MapFile.ReadVBEUint(ti.TileDataBufferStream);
wd.DataBlock = new List <Way.WayCoordinateBlock>();
for (int wcd = 0; wcd < numberOfWayCoordBlocks; wcd++)
{
//read way coordinate block
Way.WayCoordinateBlock coordBlock = new Way.WayCoordinateBlock();
coordBlock.CoordBlock = new List <Way.WayCoordinate>();
int nodesCount = (int)MapFile.ReadVBEUint(ti.TileDataBufferStream);
//Way.WayCoordinate diffwc = wc;
if (doubleEncoding)
{
// get the first way node latitude single-delta offset (VBE-S)
int wayNodeLatitude = ti.TileLatitude + MapFile.ReadVBESint(ti.TileDataBufferStream);
// get the first way node longitude single-delta offset (VBE-S)
int wayNodeLongitude = ti.TileLongitude + MapFile.ReadVBESint(ti.TileDataBufferStream);
// store the first way node
Way.WayCoordinate wc = new Way.WayCoordinate();
wc.Latitude = wayNodeLatitude;
wc.Longitude = wayNodeLongitude;
coordBlock.CoordBlock.Add(wc);
int previousSingleDeltaLatitude = 0;
int previousSingleDeltaLongitude = 0;
for (int n = 1; n < nodesCount; n++)
{
// get the way node latitude double-delta offset (VBE-S)
int doubleDeltaLatitude = MapFile.ReadVBESint(ti.TileDataBufferStream);
// get the way node longitude double-delta offset (VBE-S)
int doubleDeltaLongitude = MapFile.ReadVBESint(ti.TileDataBufferStream);
int singleDeltaLatitude = doubleDeltaLatitude + previousSingleDeltaLatitude;
int singleDeltaLongitude = doubleDeltaLongitude + previousSingleDeltaLongitude;
wayNodeLatitude = wayNodeLatitude + singleDeltaLatitude;
wayNodeLongitude = wayNodeLongitude + singleDeltaLongitude;
Way.WayCoordinate wcNext = new Way.WayCoordinate();
wcNext.Latitude = wayNodeLatitude;
wcNext.Longitude = wayNodeLongitude;
coordBlock.CoordBlock.Add(wcNext);
previousSingleDeltaLatitude = singleDeltaLatitude;
previousSingleDeltaLongitude = singleDeltaLongitude;
}
}
else
{
// get the first way node latitude single-delta offset (VBE-S)
int wayNodeLatitude = ti.TileLatitude + MapFile.ReadVBESint(ti.TileDataBufferStream);
// get the first way node longitude single-delta offset (VBE-S)
int wayNodeLongitude = ti.TileLongitude + MapFile.ReadVBESint(ti.TileDataBufferStream);
// store the first way node
Way.WayCoordinate wc = new Way.WayCoordinate();
wc.Latitude = wayNodeLatitude;
wc.Longitude = wayNodeLongitude;
coordBlock.CoordBlock.Add(wc);
for (int n = 1; n < nodesCount; n++)
{
// get the way node latitude offset (VBE-S)
wayNodeLatitude = wayNodeLatitude + MapFile.ReadVBESint(ti.TileDataBufferStream);
// get the way node longitude offset (VBE-S)
wayNodeLongitude = wayNodeLongitude + MapFile.ReadVBESint(ti.TileDataBufferStream);
Way.WayCoordinate wcNext = new Way.WayCoordinate();
wcNext.Latitude = wayNodeLatitude;
wcNext.Longitude = wayNodeLongitude;
coordBlock.CoordBlock.Add(wcNext);
}
}
wd.DataBlock.Add(coordBlock);
}
way.WayDataBlocks.Add(wd);
}
ti.Ways.Add(way);
}
}
}
}
ti.TileDataBuffer = null; //memory can be released
}
catch
{
ti = null;
}
return(ti);
}