Class Projection

Classdesc

Projection definition class. One of these is created for each projection supported in the application and stored in the ol.proj namespace. You can use these in applications, but this is not required, as API params and options use ol.ProjectionLike which means the simple string code will suffice.

You can use ol.proj.get to retrieve the object for a particular projection.

The library includes definitions for EPSG:4326 and EPSG:3857, together with the following aliases:

EPSG:4326: CRS:84, urn:ogc:def:crs:EPSG:6.6:4326, urn:ogc:def:crs:OGC:1.3:CRS84, urn:ogc:def:crs:OGC:2:84, http://www.opengis.net/gml/srs/epsg.xml#4326, urn:x-ogc:def:crs:EPSG:4326
EPSG:3857: EPSG:102100, EPSG:102113, EPSG:900913, urn:ogc:def:crs:EPSG:6.18:3:3857, http://www.opengis.net/gml/srs/epsg.xml#3857

If you use proj4js, aliases can be added using proj4.defs(); see documentation. To set an alternative namespace for proj4, use ol.proj.setProj4.

Param: options

Projection options.

Struct

Api

stable

Index

Constructors

constructor

Methods

getCode getExtent getMetersPerUnit getPointResolution getUnits getWorldExtent isGlobal setExtent setGetPointResolution setGlobal setWorldExtent

Constructors

constructor

new Projection(options): Projection
Parameters
- options: ProjectionOptions
  Projection options.
Returns Projection
Classdesc
Projection definition class. One of these is created for each projection supported in the application and stored in the ol.proj namespace. You can use these in applications, but this is not required, as API params and options use ol.ProjectionLike which means the simple string code will suffice.

You can use ol.proj.get to retrieve the object for a particular projection.

The library includes definitions for EPSG:4326 and EPSG:3857, together with the following aliases:
- EPSG:4326: CRS:84, urn:ogc:def:crs:EPSG:6.6:4326, urn:ogc:def:crs:OGC:1.3:CRS84, urn:ogc:def:crs:OGC:2:84, http://www.opengis.net/gml/srs/epsg.xml#4326, urn:x-ogc:def:crs:EPSG:4326
- EPSG:3857: EPSG:102100, EPSG:102113, EPSG:900913, urn:ogc:def:crs:EPSG:6.18:3:3857, http://www.opengis.net/gml/srs/epsg.xml#3857
If you use proj4js, aliases can be added using proj4.defs(); see documentation. To set an alternative namespace for proj4, use ol.proj.setProj4.

Struct
Api
stable
- Defined in openlayers/ol.d.cts:7276

Methods

getCode

getCode(): string
Get the code for this projection, e.g. 'EPSG:4326'.

Returns string
Code.

Api
stable
- Defined in openlayers/ol.d.cts:7283

getExtent

getExtent(): Extent
Get the validity extent for this projection.

Returns Extent
Extent.

Api
stable
- Defined in openlayers/ol.d.cts:7290

getMetersPerUnit

getMetersPerUnit(): number
Get the amount of meters per unit of this projection. If the projection is not configured with metersPerUnit or a units identifier, the return is undefined.

Returns number
Meters.

Api
stable
- Defined in openlayers/ol.d.cts:7306

getPointResolution

getPointResolution(resolution, point): number
Get the resolution of the point in degrees or distance units. For projections with degrees as the unit this will simply return the provided resolution. The default for other projections is to estimate the point resolution by transforming the 'point' pixel to EPSG:4326, measuring its width and height on the normal sphere, and taking the average of the width and height. An alternative implementation may be given when constructing a projection. For many local projections, such a custom function will return the resolution unchanged.
Parameters
- resolution: number
  Resolution in projection units.
- point: Coordinate
  Point.
Returns number
Point resolution in projection units.

Api
- Defined in openlayers/ol.d.cts:7366

getUnits

getUnits(): ol.proj.Units
Get the units of this projection.

Returns ol.proj.Units
Units.

Api
stable
- Defined in openlayers/ol.d.cts:7297

getWorldExtent

getWorldExtent(): Extent
Get the world extent for this projection.

Returns Extent
Extent.

Api
- Defined in openlayers/ol.d.cts:7313

isGlobal

isGlobal(): boolean
Is this projection a global projection which spans the whole world?

Returns boolean
Whether the projection is global.

Api
stable
- Defined in openlayers/ol.d.cts:7320

setExtent

setExtent(extent): void
Set the validity extent for this projection.
Parameters
- extent: Extent
  Extent.
Returns void
Api
stable
- Defined in openlayers/ol.d.cts:7334

setGetPointResolution

setGetPointResolution(func): void
Set the getPointResolution function for this projection.
Parameters
- func: ((resolution, coords) => number)
  Function
  - - (resolution, coords): number
    - Parameters
      resolution: number
      coords: Coordinate
      Returns number
Returns void
Api
- Defined in openlayers/ol.d.cts:7349

setGlobal

setGlobal(global): void
Set if the projection is a global projection which spans the whole world
Parameters
- global: boolean
  Whether the projection is global.
Returns void
Api
stable
- Defined in openlayers/ol.d.cts:7327

setWorldExtent

setWorldExtent(worldExtent): void
Set the world extent for this projection.
Parameters
- worldExtent: Extent
  World extent [minlon, minlat, maxlon, maxlat].
Returns void
Api
- Defined in openlayers/ol.d.cts:7342

Class Projection

Classdesc

Param: options

Struct

Api

Index

Constructors

Methods

Constructors

constructor

Parameters

options: ProjectionOptions

Returns Projection

Classdesc

Struct

Api

Methods

getCode

Returns string

Api

getExtent

Returns Extent

Api

getMetersPerUnit

Returns number

Api

getPointResolution

Parameters

resolution: number

point: Coordinate

Returns number

Api

getUnits

Returns ol.proj.Units

Api

getWorldExtent

Returns Extent

Api

isGlobal

Returns boolean

Api

setExtent

Parameters

extent: Extent

Returns void

Api

setGetPointResolution

Parameters

func: ((resolution, coords) => number)

Parameters

resolution: number

coords: Coordinate

Returns number

Returns void

Api

setGlobal

Parameters

global: boolean

Returns void

Api

setWorldExtent

Parameters

worldExtent: Extent

Returns void

Api

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