public static IEnumerable <OsmWay> DecodeWays(PrimitiveBlock data)
{
if (data == null || data.PrimitiveGroup == null)
{
yield break;
}
foreach (var way in data.PrimitiveGroup.SelectMany(x => x.Ways))
{
var ids = DecodeDeltaItems(way.Refs);
var tags = DecodeTags(way.Keys, way.Values, data.Strings);
yield return(new OsmWay
{
Id = way.Id,
NodeIds = ids,
Tags = tags
});
}
}
public PrimitiveBlock ReadData()
{
reader.BeginReadMessage(length);
var result = new PrimitiveBlock();
result.PrimitiveGroup = new List <PrimitiveGroup>();
while (reader.State == ProtobufReaderState.Field)
{
switch (reader.FieldNumber)
{
case 1:
result.Strings = ReadStringTable();
break;
case 2:
result.PrimitiveGroup.Add(ReadPrimitiveGroup());
break;
case 17:
result.Granularity = (int)reader.ReadInt64();
break;
case 19:
result.LatOffset = reader.ReadInt64();
break;
case 20:
result.LonOffset = reader.ReadInt64();
break;
case 18:
result.DateGranularity = (int)reader.ReadInt64();
break;
default:
reader.Skip();
break;
}
}
reader.EndReadMessage();
return(result);
}
public static IEnumerable <OsmNode> DecodeDenseNodes(PrimitiveBlock data)
{
if (data == null || data.PrimitiveGroup == null)
{
yield break;
}
foreach (var denseNodes in data.PrimitiveGroup.Select(group => group.DenseNodes)
.Where(denseNodes => denseNodes != null))
{
var ids = denseNodes.Ids;
var latitudes = denseNodes.Latitudes;
var longitudes = denseNodes.Longitudes;
long prevId = 0;
long prevLat = 0;
long prevLon = 0;
if (ids.Count != latitudes.Count || ids.Count != longitudes.Count)
{
throw new InvalidOperationException(
"Dense node should have equal couont of Ids, Longitudes and Latitudes");
}
for (var i = 0; i < ids.Count; i++)
{
prevId += ids[i];
prevLon += longitudes[i];
prevLat += latitudes[i];
var lon = 0.000000001 * (data.LonOffset + data.Granularity * prevLon);
var lat = 0.000000001 * (data.LatOffset + data.Granularity * prevLat);
var node = new OsmNode(prevId, lon, lat);
yield return(node);
}
}
}