CRS
CRS =
object
Defined in: geo/projection/crs.ts:33
Experimental
Describes a planar coordinate reference system (CRS) together with the square, power-of-two
quad tile grid laid over it, so a map can render tiles that were pre-projected in that CRS.
Register one with addProjection and select it with the style's projection.type
or map.setProjection({type: name}).
Every tile source of the map is taken to be cut in tileMatrixSet, and the tiles are used as they are,
without reprojecting their content. The map positions that grid on screen and maps lng/lat to and from it
through projection. CRS units are taken as meters wherever the map converts meters: altitudes, elevations,
and the camera distance.
Properties
definition?
optionaldefinition?:string
Defined in: geo/projection/crs.ts:63
The CRS as a string the workers' projection handler accepts, such as WKT or a PROJ string.
GeoJSON sources need it: their data is parsed and tiled in the workers, where projection cannot go,
so a handler set there builds the same converter from this string, see the custom CRS guide.
Without it, GeoJSON sources warn and draw in the wrong place.
name
name:
string
Defined in: geo/projection/crs.ts:39
Name used in projection.type, e.g. 'EPSG:2193' or 'custom:floor-plan'. It must contain a colon: names
without one, like 'mercator', 'globe', 'vertical-perspective' and the pre-registered 'identity', are
reserved for built-in projections.
projection
projection:
object
Defined in: geo/projection/crs.ts:49
Converts between lng/lat (degrees) and CRS coordinates (e.g. meters easting/northing): forward([lng, lat])
returns [x, y] and inverse([x, y]) returns [lng, lat]. This is the shape of a proj4 converter such as
proj4('EPSG:4326', 'EPSG:2193'), which deck.gl's custom projection view takes as well.
Where inverse has no answer, null, a value that is not finite, one that forward does not take back to the
position, or an error, as proj4 gives past the edge of world projections, the map uses the edge of the answers on the
line to the center of the tile matrix set. It assumes they form one stretch from the center outwards, so a world
projection's tile matrix set should be centered on its world.
forward()
forward(
position:number[]):number[]
Parameters
| Parameter | Type |
|---|---|
position |
number[] |
Returns
number[]
inverse()
inverse(
position:number[]):number[]
Parameters
| Parameter | Type |
|---|---|
position |
number[] |
Returns
number[]
tileMatrixSet
tileMatrixSet:
TileMatrixSet
Defined in: geo/projection/crs.ts:56
The quad tile matrix set over the CRS plane.