static WknMultiPolygon ParseMultiPolygon(byte[] wkb, ref int pos)
{
if (wkb[pos] != 1)
{
throw new Exception("Sorry, only Little Endian format is supported");
}
var type = BitConverter.ToUInt32(wkb, pos + 1);
if (type != (uint)WknGeometryType.WknMultiPolygon)
{
throw new Exception("Invalid object type");
}
var nbPolygons = BitConverter.ToUInt32(wkb, pos + 5);
pos += 9;
var polygons = new WknPolygon[nbPolygons];
for (var r = 0; r < nbPolygons; ++r)
{
polygons[r] = ParsePolygon(wkb, ref pos);
}
return(new WknMultiPolygon(polygons));
}
static void AppendPolygon(BinaryWriter wrt, WknPolygon polygon)
{
wrt.Write(LittleEndian);
wrt.Write((uint)WknGeometryType.WknPolygon);
wrt.Write((uint)polygon.Rings.Length);
for (var i = 0; i < polygon.Rings.Length; ++i)
{
var ring = polygon.Rings[i];
wrt.Write((uint)ring.Points.Length);
for (var j = 0; j < ring.Points.Length; ++j)
{
wrt.Write(ring.Points[j].X);
wrt.Write(ring.Points[j].Y);
}
}
}
