Well-Known Binary (WKB) Format
WKB stands for Well-Known Binary, a format for representing geographical and geometrical data.
WKB uses 1-byte unsigned integers, 4-byte unsigned integers, and 8-byte double-precision numbers.
The first byte indicates the byte order. 00 for big endian, or 01 for little endian.
The next 4 bytes indicate the geometry type. Values from 1 to 7 indicate whether the type is Point, LineString, Polygon, MultiPoint, MultiLineString, MultiPolygon, or GeometryCollection respectively.
The 8-byte floats represent the co-ordinates.
Take the following example, a sequence of 21 bytes each represented by two hex digits:
000000000140000000000000004010000000000000
It's big endian
000000000140000000000000004010000000000000
It's a POINT
000000000140000000000000004010000000000000
The X co-ordinate is 2.0
000000000140000000000000004010000000000000
The Y-co-ordinate is 4.0
000000000140000000000000004010000000000000
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