Decode has the protobuf library decode the data into a tile.

DecodeGzipped first ungzips the data before having the protobuf library decode the data into a tile.

Encode protobuf encodes the tile into a byte buffer.

EncodeGzipped gzips the data after encoding the tile via protocol buffers.

Features are described in section 4.2 of the specification.

Layers are described in section 4.1 of the specification.

Variant type encoding The use of values is described in section 4.1 of the specification.

GeomType is described in section 4.3.4 of the specification.