public void Read(ref uint id_begin, SubTableMeta subTable, Stream input)
{
ids = new List <List <Id> >();
long subtable_ids_begin = input.Position;
uint id_count = subTable.max_id + 1;
uint block_64ids_count = (id_count - 1) >> 6;
ushort[] block_64ids_offsets = new ushort[block_64ids_count];
for (uint i = 0; i < block_64ids_count; ++i)
{
block_64ids_offsets[i] = input.ReadValueU16();
}
for (uint j = 0; j < id_count; j += 64)
{
List <Id> ids_in_block = new List <Id>();
if (j >= 64 && j % 64 == 0)
{
long block_64ids_offset = block_64ids_offsets[(j >> 6) - 1];
if (block_64ids_offset == 0)
{
ids.Add(ids_in_block);
continue;
}
input.Position = subtable_ids_begin + block_64ids_offset;
}
uint current_size_in_bits = 0;
uint k = 0;
while (k < Math.Min(id_count - j, 64))
{
Id new_id = new Id(id_begin + j + k);
new_id.Read(ref k, ref current_size_in_bits, input);
ids_in_block.Add(new_id);
}
// Adjust offsets from the start
uint delta = ((uint)(input.Position - start)) << 3;
foreach (Id new_id in ids_in_block)
{
new_id.lo += delta;
new_id.hi += delta;
}
ids.Add(ids_in_block);
}
id_begin += id_count;
}
public long Read(Stream input)
{
first_id = input.ReadValueU32();
offset_length = input.ReadValueU32();
long save = input.Position;
offset = offset_length >> 4;
length = offset_length & 15;
// read meta data for each subtable
input.Position = offset;
sub_table_metas = new SubTableMeta[length];
for (uint i = 0; i < length; ++i)
{
sub_table_metas[i] = new SubTableMeta();
sub_table_metas[i].Read(input);
}
// read ids and bit offset (lo and hi) for each subtable
sub_table_ids = new SubTableIds[length];
uint block_first_id = first_id;
long block_position = input.Position;
for (uint i = 0; i < length; ++i)
{
input.Position = block_position;
block_first_id += sub_table_metas[i].delta_from_prev_id;
sub_table_ids[i] = new SubTableIds((uint)block_position);
sub_table_ids[i].Read(ref block_first_id, sub_table_metas[i], input);
block_position += sub_table_metas[i].size;
}
input.Position = save;
return(block_position);
}