WKBWriter
Writer for the Well-known binary format for representation of geometry.
Loader | Characteristic |
---|---|
File Extension | .wkb , |
File Type | Binary |
File Format | Well Known Binary |
Data Format | Geometry |
Supported APIs | encode , encodeSync |
Encoder Type | Synchronous |
Worker Thread Support | Yes |
Installation​
npm install @loaders.gl/wkt
npm install @loaders.gl/core
Usage​
import {WKBWriter} from '@loaders.gl/wkt';
import {encodeSync} from '@loaders.gl/core';
const geometry = {
type: "Polygon",
coordinates: [[[1, 2], [3, 4], [5, 6], [1, 2]]]
}
const arrayBuffer = encodeSync(geometry, WKBWriter, {wkt: {hasZ: false, hasM: false}})
Options​
hasZ
: Should betrue
if the GeoJSON input has Z values. These values are expected to be the third coordinate position.hasM
: Should betrue
if the GeoJSON input has M values. Thes are expected to be the third coordinate position if Z values do not exist, or fourth if Z values do exist.
Format Summary​
Well-known binary (WKB) is a binary geometry encoding to store geometries (it doesn't store attributes). It's used in databases such as PostGIS and as the internal storage format of Shapefiles. It's also being discussed as the internal storage format for a "GeoArrow" specification. WKB is defined starting on page 62 of the OGC Simple Features specification.
It's essentially a binary representation of WKT. For common geospatial types
including (Multi) Point
, Line
, and Polygon
, there's a 1:1 correspondence
between WKT/WKB and GeoJSON. WKT and WKB also support extended geometry types,
such as Curve
, Surface
, and TIN
, which don't have a correspondence to
GeoJSON.
- Coordinates can be 2-4 dimensions and are interleaved.
- Positions stored as double precision