public static Offset <Feature> CreateFeature(FlatBufferBuilder builder,
ulong fid = 0,
VectorOffset ring_countsOffset = default(VectorOffset),
VectorOffset ring_lengthsOffset = default(VectorOffset),
VectorOffset lengthsOffset = default(VectorOffset),
VectorOffset coordsOffset = default(VectorOffset),
VectorOffset propertiesOffset = default(VectorOffset))
{
builder.StartObject(6);
Feature.AddFid(builder, fid);
Feature.AddProperties(builder, propertiesOffset);
Feature.AddCoords(builder, coordsOffset);
Feature.AddLengths(builder, lengthsOffset);
Feature.AddRingLengths(builder, ring_lengthsOffset);
Feature.AddRingCounts(builder, ring_countsOffset);
return(Feature.EndFeature(builder));
}
public static byte[] ToByteBuffer(IFeature feature, GeometryType geometryType, byte dimensions, IList <ColumnMeta> columns)
{
var builder = new FlatBufferBuilder(4096);
var go = GeometryConversions.BuildGeometry(builder, feature.Geometry, geometryType, dimensions);
var memoryStream = new MemoryStream();
if (feature.Attributes != null && feature.Attributes.Count > 0 && columns != null)
{
var writer = new BinaryWriter(memoryStream, Encoding.UTF8);
for (ushort i = 0; i < columns.Count(); i++)
{
var column = columns[i];
var type = column.Type;
var name = column.Name;
if (!feature.Attributes.Exists(name))
{
continue;
}
var value = feature.Attributes[name];
if (value is null)
{
continue;
}
writer.Write(i);
switch (type)
{
case ColumnType.Bool:
writer.Write((bool)value);
break;
case ColumnType.Int:
writer.Write((int)value);
break;
case ColumnType.Long:
writer.Write((long)value);
break;
case ColumnType.Double:
writer.Write((double)value);
break;
case ColumnType.String:
var bytes = Encoding.UTF8.GetBytes((string)value);
writer.Write(bytes.Length);
writer.Write(bytes);
break;
default:
throw new ApplicationException("Unknown type " + value.GetType().FullName);
}
}
}
VectorOffset?propertiesOffset = null;
if (memoryStream.Position > 0)
{
propertiesOffset = Feature.CreatePropertiesVector(builder, memoryStream.ToArray());
}
Feature.StartFeature(builder);
Feature.AddCoords(builder, go.coordsOffset.Value);
if (go.lengthsOffset.HasValue)
{
Feature.AddLengths(builder, go.lengthsOffset.Value);
}
if (go.ringLengthsOffset.HasValue)
{
Feature.AddRingLengths(builder, go.ringLengthsOffset.Value);
}
if (go.ringCountsOffset.HasValue)
{
Feature.AddRingCounts(builder, go.ringCountsOffset.Value);
}
if (propertiesOffset.HasValue)
{
Feature.AddProperties(builder, propertiesOffset.Value);
}
var featureOffset = Feature.EndFeature(builder);
builder.FinishSizePrefixed(featureOffset.Value);
return(builder.DataBuffer.ToSizedArray());
}
