Expand description
Wire-level encoding metadata - for tile analysis and tooling.
These types describe the physical and logical encoding of streams inside an MLT tile. Normal tile consumers (parse -> iterate features) do not need this module; it is intended for tools that inspect or report encoding statistics.
Structs§
- Alp
- ALP parameters:
v = (base + offset) * 10^f / 10^e. Written as three header varints, the stream itself holding the unsigned offsets. - IntEncoding
- Morton
- Metadata for Morton decoding
- Stream
Meta - Metadata about an encoded stream
Enums§
- Bool
Logical - Logical encoding of a bool column’s data stream or a presence bitfield.
- Column
Type - Column data type, as stored in the tile.
- Dictionary
Type - Dictionary type used for a column, as stored in the tile
- FastP
ForKind - The
FastPForblock size and word order a wire version codes its integer streams with. - Float
Logical - Logical encoding of a float column’s data stream.
- IntLogical
- Logical encoding of a stream of integer values. Covers the id columns, the integer property columns, and the geometry length and offset streams.
- Length
Type - Length type used for a column, as stored in the tile
- Logical
Encoding - How should the stream be interpreted at the logical level (second pass of decoding)
- Logical
Technique - Logical encoding technique used for a column, as stored in the tile
- Offset
Type - Offset type used for a column, as stored in the tile
- Physical
Encoding - Physical encoding used for a column, as stored in the tile
- RleLayout
- Which RLE stream layout the encoder should produce.
- RleMeta
- Metadata for RLE decoding, one variant per
RleLayout. - Stat
Type - What to calculate with
Analyze::collect_statistic. - Stream
Type - How should the stream be interpreted at the physical level (first pass of decoding)
- Value
Kind - What kind of values a stream holds, which fixes the encodings it can name. Neither wire format stores it: v1 reads it from the column type, v2 from the stream’s context.
- Vertex
Logical - Logical encoding of a geometry vertex stream, whose values are interleaved coordinate pairs.
Traits§
- Analyze
- Trait for estimating various size/count metrics.