The Coordinate Reference Systems Library was developed at the National Geospatial-Intelligence Agency (NGA) in collaboration with BIT Systems. The government has "unlimited rights" and is releasing this software to increase the impact of government investments by providing developers with the opportunity to take things in new directions. The software use, modification, and distribution rights are stipulated within the MIT license.
If you'd like to contribute to this project, please make a pull request. We'll review the pull request and discuss the changes. All pull request contributions to this project will be released under the MIT license.
Software source code previously released under an open source license and then modified by NGA staff is considered a "joint work" (see 17 USC § 101); it is partially copyrighted, partially public domain, and as a whole is protected by the copyrights of the non-government authors and must be released according to the terms of the original open source license.
Coordinate Reference Systems is an iOS library implementation of OGC's 'Geographic information — Well-known text representation of coordinate reference systems' (18-010r7) specification.
For projection conversions between coordinates, see Projections.
View the latest Appledoc
@import CoordinateReferenceSystems;
// NSString *wkt = ...
CRSObject *crs = [CRSReader read:wkt];
CRSType type = crs.type;
CRSCategoryType category = crs.categoryType;
NSString *text = [CRSWriter write:crs];
NSString *prettyText = [CRSWriter writePretty:crs];
switch(category){
case CRS_CATEGORY_CRS:
{
CRSCoordinateReferenceSystem *coordRefSys = (CRSCoordinateReferenceSystem *) crs;
switch (type) {
case CRS_TYPE_BOUND:
{
CRSBoundCoordinateReferenceSystem *bound = (CRSBoundCoordinateReferenceSystem *) coordRefSys;
// ...
break;
}
case CRS_TYPE_COMPOUND:
{
CRSCompoundCoordinateReferenceSystem *compound = (CRSCompoundCoordinateReferenceSystem *) coordRefSys;
// ...
break;
}
case CRS_TYPE_DERIVED:
{
CRSDerivedCoordinateReferenceSystem *derived = (CRSDerivedCoordinateReferenceSystem *) coordRefSys;
// ...
break;
}
case CRS_TYPE_ENGINEERING:
{
CRSEngineeringCoordinateReferenceSystem *engineering = (CRSEngineeringCoordinateReferenceSystem *) coordRefSys;
// ...
break;
}
case CRS_TYPE_GEODETIC:
case CRS_TYPE_GEOGRAPHIC:
{
CRSGeoCoordinateReferenceSystem *geo = (CRSGeoCoordinateReferenceSystem *) coordRefSys;
// ...
break;
}
case CRS_TYPE_PARAMETRIC:
{
CRSParametricCoordinateReferenceSystem *parametric = (CRSParametricCoordinateReferenceSystem *) coordRefSys;
// ...
break;
}
case CRS_TYPE_PROJECTED:
{
CRSProjectedCoordinateReferenceSystem *projected = (CRSProjectedCoordinateReferenceSystem *) coordRefSys;
// ...
break;
}
case CRS_TYPE_TEMPORAL:
{
CRSTemporalCoordinateReferenceSystem *temporal = (CRSTemporalCoordinateReferenceSystem *) coordRefSys;
// ...
break;
}
case CRS_TYPE_VERTICAL:
{
CRSVerticalCoordinateReferenceSystem *vertical = (CRSVerticalCoordinateReferenceSystem *) coordRefSys;
// ...
break;
}
default:
break;
}
// ...
break;
}
case CRS_CATEGORY_METADATA:
{
CRSCoordinateMetadata *metadata = (CRSCoordinateMetadata *) crs;
// ...
break;
}
case CRS_CATEGORY_OPERATION:
{
CRSOperation *operation = (CRSOperation *) crs;
switch (type) {
case CRS_TYPE_CONCATENATED_OPERATION:
{
CRSConcatenatedOperation *concatenatedOperation = (CRSConcatenatedOperation *) operation;
// ...
break;
}
case CRS_TYPE_COORDINATE_OPERATION:
{
CRSCoordinateOperation *coordinateOperation = (CRSCoordinateOperation *) operation;
// ...
break;
}
case CRS_TYPE_POINT_MOTION_OPERATION:
{
CRSPointMotionOperation *pointMotionOperation = (CRSPointMotionOperation *) operation;
// ...
break;
}
default:
break;
}
// ...
break;
}
}
// NSString *wkt = ...
CRSObject *crs = [CRSReader read:wkt];
CRSProjParams *projParamsFromCRS = [CRSProjParser paramsFromCRS:crs];
NSString *projTextFromCRS = [CRSProjParser paramsTextFromCRS:crs];
CRSProjParams *projParamsFromWKT = [CRSProjParser paramsFromText:wkt];
NSString *projTextFromWKT = [CRSProjParser paramsTextFromText:wkt];
Build this repository using Swift Package Manager:
swift build
Run tests from Xcode or from command line:
swift test
Open the Swift Package in Xcode from command line:
open Package.swift
Use this library via SPM in your Package.swift:
dependencies: [
.package(url: "https://github.com/ngageoint/coordinate-reference-systems-ios.git", branch: "release/2.0.0"),
]
Or as a tagged release:
dependencies: [
.package(url: "https://github.com/ngageoint/coordinate-reference-systems-ios.git", from: "2.0.0"),
]
Reference it in your Package.swift target:
.target(
name: "projections",
dependencies: [
.product(name: "CoordinateReferenceSystems", package: "coordinate-reference-systems-ios"),
],
),
Import the framework in Swift.
import CoordinateReferenceSystems
// var wkt: String = ...
let crs : CRSObject = CRSReader.read(wkt)
var type : CRSType = crs.type
var category : CRSCategoryType = crs.categoryType()
let text : String = CRSWriter.write(crs)
let prettyText : String = CRSWriter.writePretty(crs)
switch category{
case .CATEGORY_CRS:
let coordRefSys : CRSCoordinateReferenceSystem = crs as! CRSCoordinateReferenceSystem
switch type {
case .TYPE_BOUND:
let bound : CRSBoundCoordinateReferenceSystem = coordRefSys as! CRSBoundCoordinateReferenceSystem
// ...
break
case .TYPE_COMPOUND:
let compound : CRSCompoundCoordinateReferenceSystem = coordRefSys as! CRSCompoundCoordinateReferenceSystem
// ...
break
case .TYPE_DERIVED:
let derived : CRSDerivedCoordinateReferenceSystem = coordRefSys as! CRSDerivedCoordinateReferenceSystem
// ...
break
case .TYPE_ENGINEERING:
let engineering : CRSEngineeringCoordinateReferenceSystem = coordRefSys as! CRSEngineeringCoordinateReferenceSystem
// ...
break
case .TYPE_GEODETIC, .TYPE_GEOGRAPHIC:
let geo : CRSGeoCoordinateReferenceSystem = coordRefSys as! CRSGeoCoordinateReferenceSystem
// ...
break
case .TYPE_PARAMETRIC:
let parametric : CRSParametricCoordinateReferenceSystem = coordRefSys as! CRSParametricCoordinateReferenceSystem
// ...
break
case .TYPE_PROJECTED:
let projected : CRSProjectedCoordinateReferenceSystem = coordRefSys as! CRSProjectedCoordinateReferenceSystem
// ...
break
case .TYPE_TEMPORAL:
let temporal : CRSTemporalCoordinateReferenceSystem = coordRefSys as! CRSTemporalCoordinateReferenceSystem
// ...
break
case .TYPE_VERTICAL:
let vertical : CRSVerticalCoordinateReferenceSystem = coordRefSys as! CRSVerticalCoordinateReferenceSystem
// ...
break
default:
break
}
// ...
break
case .CATEGORY_METADATA:
let metadata : CRSCoordinateMetadata = crs as! CRSCoordinateMetadata
// ...
break
case .CATEGORY_OPERATION:
let operation = crs as! CRSOperation
switch type {
case .TYPE_CONCATENATED_OPERATION:
let concatenatedOperation : CRSConcatenatedOperation = operation as! CRSConcatenatedOperation
// ...
break
case .TYPE_COORDINATE_OPERATION:
let coordinateOperation : CRSCoordinateOperation = operation as! CRSCoordinateOperation
// ...
break
case .TYPE_POINT_MOTION_OPERATION:
let pointMotionOperation : CRSPointMotionOperation = operation as! CRSPointMotionOperation
// ...
break
default:
break
}
// ...
break
default:
break
}// var wkt: String = ...
let crs : CRSObject = CRSReader.read(wkt)
let projParamsFromCRS : CRSProjParams = CRSProjParser.params(fromCRS: crs)
let projTextFromCRS : String = CRSProjParser.paramsText(fromCRS: crs)
let projParamsFromWKT : CRSProjParams = CRSProjParser.params(fromText: wkt)
let projTextFromWKT : String = CRSProjParser.paramsText(fromText: wkt)