private void decodeWayNodesSingleDelta(List <Point> waySegment, double tileLatitude, double tileLongitude, ReadBuffer readBuffer)
{
// get the first way node latitude single-delta offset (VBE-S)
double wayNodeLatitude = tileLatitude + PointUtils.MicrodegreesToDegrees(readBuffer.ReadSignedInt());
// get the first way node longitude single-delta offset (VBE-S)
double wayNodeLongitude = tileLongitude + PointUtils.MicrodegreesToDegrees(readBuffer.ReadSignedInt());
// store the first way node
waySegment.Add(new Point(wayNodeLongitude, wayNodeLatitude));
for (int wayNodesIndex = 1; wayNodesIndex < waySegment.Capacity; ++wayNodesIndex)
{
// get the way node latitude offset (VBE-S)
wayNodeLatitude = wayNodeLatitude + PointUtils.MicrodegreesToDegrees(readBuffer.ReadSignedInt());
// get the way node longitude offset (VBE-S)
wayNodeLongitude = wayNodeLongitude + PointUtils.MicrodegreesToDegrees(readBuffer.ReadSignedInt());
// Decoding near international date line can return values slightly outside valid [-180°, 180°] due to calculation precision
if (wayNodeLongitude < PointUtils.LONGITUDE_MIN &&
(PointUtils.LONGITUDE_MIN - wayNodeLongitude) < 0.001)
{
wayNodeLongitude = PointUtils.LONGITUDE_MIN;
}
else if (wayNodeLongitude > PointUtils.LONGITUDE_MAX &&
(wayNodeLongitude - PointUtils.LONGITUDE_MAX) < 0.001)
{
wayNodeLongitude = PointUtils.LONGITUDE_MAX;
}
waySegment.Add(new Point(wayNodeLongitude, wayNodeLatitude));
}
}
private Point ReadOptionalLabelPosition(double tileLatitude, double tileLongitude, bool featureLabelPosition, ReadBuffer readBuffer)
{
if (featureLabelPosition)
{
// get the label position latitude offset (VBE-S)
double latitude = tileLatitude + PointUtils.MicrodegreesToDegrees(readBuffer.ReadSignedInt());
// get the label position longitude offset (VBE-S)
double longitude = tileLongitude + PointUtils.MicrodegreesToDegrees(readBuffer.ReadSignedInt());
return(new Point(longitude, latitude));
}
return(null);
}
private IList <PointOfInterest> ProcessPOIs(double tileLatitude, double tileLongitude, int numberOfPois, BoundingBox boundingBox, bool filterRequired, ReadBuffer readBuffer)
{
IList <PointOfInterest> pois = new List <PointOfInterest>();
Tag[] poiTags = this.mapFileHeader.MapFileInfo.PoiTags;
for (int elementCounter = numberOfPois; elementCounter != 0; --elementCounter)
{
if (this.mapFileHeader.MapFileInfo.DebugFile)
{
// get and check the POI signature
string signaturePoi = readBuffer.ReadUTF8EncodedString(SIGNATURE_LENGTH_POI);
if (!signaturePoi.StartsWith("***POIStart", StringComparison.Ordinal))
{
Logger.Log(LogLevel.Warning, "invalid POI signature: " + signaturePoi);
return(null);
}
}
// get the POI latitude offset (VBE-S)
double latitude = tileLatitude + PointUtils.MicrodegreesToDegrees(readBuffer.ReadSignedInt());
// get the POI longitude offset (VBE-S)
double longitude = tileLongitude + PointUtils.MicrodegreesToDegrees(readBuffer.ReadSignedInt());
// get the special byte which encodes multiple flags
sbyte specialByte = readBuffer.ReadByte();
// bit 1-4 represent the layer with
sbyte layer = (sbyte)((int)((uint)(specialByte & POI_LAYER_BITMASK) >> POI_LAYER_SHIFT));
// bit 5-8 represent the number of tag IDs
sbyte numberOfTags = (sbyte)(specialByte & POI_NUMBER_OF_TAGS_BITMASK);
IList <Tag> tags = new List <Tag>();
// get the tag IDs (VBE-U)
for (sbyte tagIndex = numberOfTags; tagIndex != 0; --tagIndex)
{
int tagId = readBuffer.ReadUnsignedInt();
if (tagId < 0 || tagId >= poiTags.Length)
{
Logger.Log(LogLevel.Warning, "invalid POI tag ID: " + tagId);
return(null);
}
tags.Add(poiTags[tagId]);
}
// get the feature bitmask (1 byte)
sbyte featureByte = readBuffer.ReadByte();
// bit 1-3 enable optional features
bool featureName = (featureByte & POI_FEATURE_NAME) != 0;
bool featureHouseNumber = (featureByte & POI_FEATURE_HOUSE_NUMBER) != 0;
bool featureElevation = (featureByte & POI_FEATURE_ELEVATION) != 0;
// check if the POI has a name
if (featureName)
{
tags.Add(new Tag(TAG_KEY_NAME, ExtractLocalized(readBuffer.ReadUTF8EncodedString())));
}
// check if the POI has a house number
if (featureHouseNumber)
{
tags.Add(new Tag(TAG_KEY_HOUSE_NUMBER, readBuffer.ReadUTF8EncodedString()));
}
// check if the POI has an elevation
if (featureElevation)
{
tags.Add(new Tag(TAG_KEY_ELE, Convert.ToString(readBuffer.ReadSignedInt())));
}
Point position = new Point(longitude, latitude);
// depending on the zoom level configuration the poi can lie outside
// the tile requested, we filter them out here
if (!filterRequired || boundingBox.Contains(position))
{
pois.Add(new PointOfInterest(layer, tags, position));
}
}
return(pois);
}