#include <stddef.h>

Include dependency graph for proj.h:

Typedefs
typedef char **	PROJ_STRING_LIST
	Type representing a NULL terminated list of NUL-terminate strings.

Enumerations
enum	PJ_OBJ_CATEGORY { PJ_OBJ_CATEGORY_ELLIPSOID, PJ_OBJ_CATEGORY_DATUM, PJ_OBJ_CATEGORY_CRS, PJ_OBJ_CATEGORY_COORDINATE_OPERATION }
	Object category.

enum	PJ_OBJ_TYPE { PJ_OBJ_TYPE_ELLIPSOID, PJ_OBJ_TYPE_GEODETIC_REFERENCE_FRAME, PJ_OBJ_TYPE_DYNAMIC_GEODETIC_REFERENCE_FRAME, PJ_OBJ_TYPE_VERTICAL_REFERENCE_FRAME, PJ_OBJ_TYPE_DYNAMIC_VERTICAL_REFERENCE_FRAME, PJ_OBJ_TYPE_DATUM_ENSEMBLE, PJ_OBJ_TYPE_GEODETIC_CRS, PJ_OBJ_TYPE_GEOGRAPHIC_CRS, PJ_OBJ_TYPE_VERTICAL_CRS, PJ_OBJ_TYPE_PROJECTED_CRS, PJ_OBJ_TYPE_COMPOUND_CRS, PJ_OBJ_TYPE_TEMPORAL_CRS, PJ_OBJ_TYPE_BOUND_CRS, PJ_OBJ_TYPE_OTHER_CRS, PJ_OBJ_TYPE_CONVERSION, PJ_OBJ_TYPE_TRANSFORMATION, PJ_OBJ_TYPE_CONCATENATED_OPERATION, PJ_OBJ_TYPE_OTHER_COORDINATE_OPERATION, PJ_OBJ_TYPE_UNKNOWN }
	Object type.

enum	PJ_WKT_TYPE { PJ_WKT2_2018, PJ_WKT2_2018_SIMPLIFIED, PJ_WKT2_2015, PJ_WKT2_2015_SIMPLIFIED, PJ_WKT1_GDAL }
	WKT version. More...

enum	PJ_PROJ_STRING_TYPE { PJ_PROJ_5, PJ_PROJ_4 }
	PROJ string version. More...

enum	PROJ_CRS_EXTENT_USE { PJ_CRS_EXTENT_NONE, PJ_CRS_EXTENT_BOTH, PJ_CRS_EXTENT_INTERSECTION, PJ_CRS_EXTENT_SMALLEST }

enum	PROJ_SPATIAL_CRITERION { PROJ_SPATIAL_CRITERION_STRICT_CONTAINMENT, PROJ_SPATIAL_CRITERION_PARTIAL_INTERSECTION }

enum	PROJ_GRID_AVAILABILITY_USE { PROJ_GRID_AVAILABILITY_USED_FOR_SORTING, PROJ_GRID_AVAILABILITY_DISCARD_OPERATION_IF_MISSING_GRID, PROJ_GRID_AVAILABILITY_IGNORED }

Functions
int	proj_context_set_database_path (PJ_CONTEXT ctx, const char dbPath, const char const auxDbPaths)
	Explicitly point to the main PROJ CRS and coordinate operation definition database ("proj.db"), and potentially auxiliary databases with same structure. More...

const char *	proj_context_get_database_path (PJ_CONTEXT *ctx)
	Returns the path to the database. More...

PJ_OBJ *	proj_obj_create_from_user_input (PJ_CONTEXT ctx, const char text)
	Instanciate an object from a WKT string, PROJ string or object code (like "EPSG:4326", "urn:ogc:def:crs:EPSG::4326", "urn:ogc:def:coordinateOperation:EPSG::1671"). More...

PJ_OBJ *	proj_obj_create_from_wkt (PJ_CONTEXT ctx, const char wkt)
	Instanciate an object from a WKT string. More...

PJ_OBJ *	proj_obj_create_from_proj_string (PJ_CONTEXT ctx, const char proj_string)
	Instanciate an object from a PROJ string. More...

PJ_OBJ *	proj_obj_create_from_database (PJ_CONTEXT ctx, const char auth_name, const char code, PJ_OBJ_CATEGORY category, int usePROJAlternativeGridNames, const char const *options)
	Instanciate an object from a database lookup. More...

void	proj_obj_unref (PJ_OBJ *obj)
	Drops a reference on an object. More...

PJ_OBJ_TYPE	proj_obj_get_type (PJ_OBJ *obj)
	Return the type of an object. More...

PROJ_STRING_LIST	proj_get_authorities_from_database (PJ_CONTEXT *ctx)
	Return the list of authorities used in the database. More...

PROJ_STRING_LIST	proj_get_codes_from_database (PJ_CONTEXT ctx, const char auth_name, PJ_OBJ_TYPE type, int allow_deprecated)
	Returns the set of authority codes of the given object type. More...

void	proj_free_string_list (PROJ_STRING_LIST list)

int	proj_obj_is_crs (PJ_OBJ *obj)
	Return whether an object is a CRS. More...

const char *	proj_obj_get_name (PJ_OBJ *obj)
	Get the name of an object. More...

const char *	proj_obj_get_id_auth_name (PJ_OBJ *obj, int index)
	Get the authority name / codespace of an identifier of an object. More...

const char *	proj_obj_get_id_code (PJ_OBJ *obj, int index)
	Get the code of an identifier of an object. More...

const char *	proj_obj_as_wkt (PJ_OBJ obj, PJ_WKT_TYPE type, const char const *options)
	Get a WKT representation of an object. More...

const char *	proj_obj_as_proj_string (PJ_OBJ obj, PJ_PROJ_STRING_TYPE type, const char const *options)
	Get a PROJ string representation of an object. More...

PJ_OBJ *	proj_obj_get_source_crs (PJ_OBJ *obj)
	Return the base CRS of a BoundCRS or the source CRS of a CoordinateOperation. More...

PJ_OBJ *	proj_obj_get_target_crs (PJ_OBJ *obj)
	Return the hub CRS of a BoundCRS or the target CRS of a CoordinateOperation. More...

PJ_OPERATION_FACTORY_CONTEXT *	proj_create_operation_factory_context (PJ_CONTEXT ctx, const char authority)
	Instanciate a context for building coordinate operations between two CRS. More...

void	proj_operation_factory_context_unref (PJ_OPERATION_FACTORY_CONTEXT *ctxt)
	Drops a reference on an object. More...

void	proj_operation_factory_context_set_desired_accuracy (PJ_OPERATION_FACTORY_CONTEXT *ctxt, double accuracy)
	Set the desired accuracy of the resulting coordinate transformations. More...

void	proj_operation_factory_context_set_area_of_interest (PJ_OPERATION_FACTORY_CONTEXT *ctxt, double west_lon, double south_lat, double east_lon, double north_lat)
	Set the desired area of interest for the resulting coordinate transformations. More...

void	proj_operation_factory_context_set_crs_extent_use (PJ_OPERATION_FACTORY_CONTEXT *ctxt, PROJ_CRS_EXTENT_USE use)
	Set how source and target CRS extent should be used when considering if a transformation can be used (only takes effect if no area of interest is explicitly defined). More...

void	proj_operation_factory_context_set_spatial_criterion (PJ_OPERATION_FACTORY_CONTEXT *ctxt, PROJ_SPATIAL_CRITERION criterion)
	Set the spatial criterion to use when comparing the area of validity of coordinate operations with the area of interest / area of validity of source and target CRS. More...

void	proj_operation_factory_context_set_grid_availability_use (PJ_OPERATION_FACTORY_CONTEXT *ctxt, PROJ_GRID_AVAILABILITY_USE use)
	Set how grid availability is used. More...

void	proj_operation_factory_context_set_use_proj_alternative_grid_names (PJ_OPERATION_FACTORY_CONTEXT *ctxt, int usePROJNames)
	Set whether PROJ alternative grid names should be substituted to the official authority names. More...

void	proj_operation_factory_context_set_allow_use_intermediate_crs (PJ_OPERATION_FACTORY_CONTEXT *ctxt, int allow)
	Set whether an intermediate pivot CRS can be used for researching coordinate operations between a source and target CRS. More...

void	proj_operation_factory_context_set_allowed_intermediate_crs (PJ_OPERATION_FACTORY_CONTEXT ctxt, const char const *list_of_auth_name_codes)
	Restrict the potential pivot CRSs that can be used when trying to build a coordinate operation between two CRS that have no direct operation. More...

PJ_OPERATION_RESULT *	proj_obj_create_operations (PJ_OBJ source_crs, PJ_OBJ target_crs, PJ_OPERATION_FACTORY_CONTEXT *operationContext)
	Find a list of CoordinateOperation from source_crs to target_crs. More...

int	proj_operation_result_get_count (PJ_OPERATION_RESULT *result)
	Return the number of CoordinateOperation in the result set. More...

PJ_OBJ *	proj_operation_result_get (PJ_OPERATION_RESULT *result, int index)
	Return a CoordinateOperation in the result set. More...

void	proj_operation_result_unref (PJ_OPERATION_RESULT *result)
	Drops a reference on an object. More...

PJ_OBJ *	proj_obj_crs_get_geodetic_crs (PJ_OBJ *crs)
	Get the geodeticCRS / geographicCRS from a CRS. More...

PJ_OBJ *	proj_obj_crs_get_horizontal_datum (PJ_OBJ *crs)
	Get the horizontal datum from a CRS. More...

PJ_OBJ *	proj_obj_crs_get_sub_crs (PJ_OBJ *crs, int index)
	Get a CRS component from a CompoundCRS. More...

PJ_OBJ *	proj_obj_crs_create_bound_crs_to_WGS84 (PJ_OBJ *crs)
	Returns potentially a BoundCRS, with a transformation to EPSG:4326, wrapping this CRS. More...

PJ_OBJ *	proj_obj_get_ellipsoid (PJ_OBJ *obj)
	Get the ellipsoid from a CRS or a GeodeticReferenceFrame. More...

int	proj_obj_ellipsoid_get_parameters (PJ_OBJ ellipsoid, double pSemiMajorMetre, double pSemiMinorMetre, int pIsSemiMinorComputed, double *pInverseFlattening)
	Return ellipsoid parameters. More...

PJ_OBJ *	proj_obj_get_prime_meridian (PJ_OBJ *obj)
	Get the prime meridian of a CRS or a GeodeticReferenceFrame. More...

int	proj_obj_prime_meridian_get_parameters (PJ_OBJ prime_meridian, double pLongitude, double pLongitudeUnitConvFactor, const char *pLongitudeUnitName)
	Return prime meridian parameters. More...

PJ_OBJ *	proj_obj_crs_get_coordoperation (PJ_OBJ crs, const char pMethodName, const char pMethodAuthorityName, const char *pMethodCode)
	Return the Conversion of a DerivedCRS (such as a ProjectedCRS), or the Transformation from the baseCRS to the hubCRS of a BoundCRS. More...

int	proj_coordoperation_is_instanciable (PJ_OBJ *coordoperation)
	Return whether a coordinate operation can be instanciated as a PROJ pipeline, checking in particular that referenced grids are available. More...

int	proj_coordoperation_get_param_count (PJ_OBJ *coordoperation)
	Return the number of parameters of a SingleOperation. More...

int	proj_coordoperation_get_param_index (PJ_OBJ coordoperation, const char name)
	Return the index of a parameter of a SingleOperation. More...

int	proj_coordoperation_get_param (PJ_OBJ coordoperation, int index, const char pName, const char pNameAuthorityName, const char pNameCode, double pValue, const char *pValueString, double pValueUnitConvFactor, const char **pValueUnitName)
	Return a parameter of a SingleOperation. More...

int	proj_coordoperation_get_grid_used_count (PJ_OBJ *coordoperation)
	Return the number of grids used by a CoordinateOperation. More...

int	proj_coordoperation_get_grid_used (PJ_OBJ coordoperation, int index, const char pShortName, const char pFullName, const char pPackageName, const char pURL, int pDirectDownload, int pOpenLicense, int pAvailable)
	Return a parameter of a SingleOperation. More...

Detailed Description

C API new generation

Enumeration Type Documentation

enum PJ_PROJ_STRING_TYPE

PROJ string version.

Enumerator
PJ_PROJ_5	cf osgeo::proj::io::PROJStringFormatter::Convention::PROJ_5
PJ_PROJ_4	cf osgeo::proj::io::PROJStringFormatter::Convention::PROJ_4

enum PJ_WKT_TYPE

WKT version.

Enumerator
PJ_WKT2_2018	cf osgeo::proj::io::WKTFormatter::Convention::WKT2_2018
PJ_WKT2_2018_SIMPLIFIED	cf osgeo::proj::io::WKTFormatter::Convention::WKT2_2018_SIMPLIFIED
PJ_WKT2_2015	cf osgeo::proj::io::WKTFormatter::Convention::WKT2
PJ_WKT2_2015_SIMPLIFIED	cf osgeo::proj::io::WKTFormatter::Convention::WKT2_SIMPLIFIED
PJ_WKT1_GDAL	cf osgeo::proj::io::WKTFormatter::Convention::WKT1_GDAL

enum PROJ_CRS_EXTENT_USE

Specify how source and target CRS extent should be used to restrict candidate operations (only taken into account if no explicit area of interest is specified.

Enumerator
PJ_CRS_EXTENT_NONE	Ignore CRS extent
PJ_CRS_EXTENT_BOTH	Test coordinate operation extent against both CRS extent.
PJ_CRS_EXTENT_INTERSECTION	Test coordinate operation extent against the intersection of both CRS extent.
PJ_CRS_EXTENT_SMALLEST	Test coordinate operation against the smallest of both CRS extent.

enum PROJ_GRID_AVAILABILITY_USE

Describe how grid availability is used.

Enumerator
PROJ_GRID_AVAILABILITY_USED_FOR_SORTING	Grid availability is only used for sorting results. Operations where some grids are missing will be sorted last.
PROJ_GRID_AVAILABILITY_DISCARD_OPERATION_IF_MISSING_GRID	Completely discard an operation if a required grid is missing.
PROJ_GRID_AVAILABILITY_IGNORED	Ignore grid availability at all. Results will be presented as if all grids were available.

enum PROJ_SPATIAL_CRITERION

Spatial criterion to restrict candiate operations.

Enumerator
PROJ_SPATIAL_CRITERION_STRICT_CONTAINMENT	The area of validity of transforms should strictly contain the are of interest.
PROJ_SPATIAL_CRITERION_PARTIAL_INTERSECTION	The area of validity of transforms should at least intersect the area of interest.

Function Documentation

const char* proj_context_get_database_path ( PJ_CONTEXT * ctx )

Returns the path to the database.

The returned pointer remains valid while ctx is valid, and until proj_context_set_database_path() is called.

Parameters

ctx	PROJ context, or NULL for default context

Returns: path, or nullptr

int proj_context_set_database_path	(	PJ_CONTEXT *	ctx,
		const char *	dbPath,
		const char const	auxDbPaths
	)

Explicitly point to the main PROJ CRS and coordinate operation definition database ("proj.db"), and potentially auxiliary databases with same structure.

Parameters

ctx	PROJ context, or NULL for default context
dbPath	Path to main database, or NULL for default.
auxDbPaths	NULL-terminated list of auxiliary database filenames, or NULL.

Returns: TRUE in case of success

int proj_coordoperation_get_grid_used	(	PJ_OBJ *	coordoperation,
		int	index,
		const char **	pShortName,
		const char **	pFullName,
		const char **	pPackageName,
		const char **	pURL,
		int *	pDirectDownload,
		int *	pOpenLicense,
		int *	pAvailable
	)

Return a parameter of a SingleOperation.

Parameters

coordoperation	Objet of type SingleOperation or derived classes (must not be NULL)
index	Parameter index.
pShortName	Pointer to a string value to store the grid short name. or NULL
pFullName	Pointer to a string value to store the grid full filename. or NULL
pPackageName	Pointer to a string value to store the package name where the grid might be found. or NULL
pURL	Pointer to a string value to store the grid URL or the package URL where the grid might be found. or NULL
pDirectDownload	Pointer to a int (boolean) value to store whether *pURL can be downloaded directly. or NULL
pOpenLicense	Pointer to a int (boolean) value to store whether the grid is released with an open license. or NULL
pAvailable	Pointer to a int (boolean) value to store whether the grid is available at runtime. or NULL

Returns: TRUE in case of success.

int proj_coordoperation_get_grid_used_count ( PJ_OBJ * coordoperation )

Return the number of grids used by a CoordinateOperation.

Parameters

coordoperation Objet of type CoordinateOperation or derived classes (must not be NULL)

int proj_coordoperation_get_param	(	PJ_OBJ *	coordoperation,
		int	index,
		const char **	pName,
		const char **	pNameAuthorityName,
		const char **	pNameCode,
		double *	pValue,
		const char **	pValueString,
		double *	pValueUnitConvFactor,
		const char **	pValueUnitName
	)

Return a parameter of a SingleOperation.

Parameters

coordoperation	Objet of type SingleOperation or derived classes (must not be NULL)
index	Parameter index.
pName	Pointer to a string value to store the parameter name. or NULL
pNameAuthorityName	Pointer to a string value to store the parameter authority name. or NULL
pNameCode	Pointer to a string value to store the parameter code. or NULL
pValue	Pointer to a double value to store the parameter value (if numeric). or NULL
pValueString	Pointer to a string value to store the parameter value (if of type string). or NULL
pValueUnitConvFactor	Pointer to a double value to store the parameter unit conversion factor. or NULL
pValueUnitName	Pointer to a string value to store the parameter unit name. or NULL

Returns: TRUE in case of success.

int proj_coordoperation_get_param_count ( PJ_OBJ * coordoperation )

Return the number of parameters of a SingleOperation.

Parameters

coordoperation Objet of type SingleOperation or derived classes (must not be NULL)

int proj_coordoperation_get_param_index	(	PJ_OBJ *	coordoperation,
		const char *	name
	)

Return the index of a parameter of a SingleOperation.

Parameters

coordoperation	Objet of type SingleOperation or derived classes (must not be NULL)
name	Parameter name. Must not be NULL

Returns: index (>=0), or -1 in case of error.

int proj_coordoperation_is_instanciable ( PJ_OBJ * coordoperation )

Return whether a coordinate operation can be instanciated as a PROJ pipeline, checking in particular that referenced grids are available.

Parameters

coordoperation Objet of type CoordinateOperation or derived classes (must not be NULL)

Returns: TRUE or FALSE.

PJ_OPERATION_FACTORY_CONTEXT* proj_create_operation_factory_context	(	PJ_CONTEXT *	ctx,
		const char *	authority
	)

Instanciate a context for building coordinate operations between two CRS.

The returned object must be unreferenced with proj_operation_factory_context_unref() after use.

Parameters

ctx	Context, or NULL for default context.
authority	Name of authority to which to restrict the search of canidate operations. Or NULL to allow any authority.

Returns: Object that must be unreferenced with proj_operation_factory_context_unref(), or NULL in case of error.

void proj_free_string_list ( PROJ_STRING_LIST list )

Free a list of NULL terminated strings.

PROJ_STRING_LIST proj_get_authorities_from_database ( PJ_CONTEXT * ctx )

Return the list of authorities used in the database.

The returned list is NULL terminated and must be freed with proj_free_string_list().

Parameters

ctx	PROJ context, or NULL for default context

Returns: a NULL terminated list of NUL-terminated strings that must be freed with proj_free_string_list(), or NULL in case of error.

PROJ_STRING_LIST proj_get_codes_from_database	(	PJ_CONTEXT *	ctx,
		const char *	auth_name,
		PJ_OBJ_TYPE	type,
		int	allow_deprecated
	)

Returns the set of authority codes of the given object type.

The returned list is NULL terminated and must be freed with proj_free_string_list().

Parameters

ctx	PROJ context, or NULL for default context.
auth_name	Authority name (must not be NULL)
type	Object type.
allow_deprecated	whether we should return deprecated objects as well.

Returns: a NULL terminated list of NUL-terminated strings that must be freed with proj_free_string_list(), or NULL in case of error.

const char* proj_obj_as_proj_string	(	PJ_OBJ *	obj,
		PJ_PROJ_STRING_TYPE	type,
		const char const	options
	)

Get a PROJ string representation of an object.

The lifetime of the returned string is the same as the input obj parameter.

This function calls osgeo::proj::io::IPROJStringExportable::exportToPROJString().

This function may return NULL if the object is not compatible with an export to the requested type.

Parameters

obj	Object (must not be NULL)
type	PROJ String version.
options	NULL-terminated list of strings with "KEY=VALUE" format. or NULL. The currently recognized option is USE_ETMERC=YES to use +proj=etmerc instead of +proj=tmerc

Returns: a string, or NULL in case of error.

const char* proj_obj_as_wkt	(	PJ_OBJ *	obj,
		PJ_WKT_TYPE	type,
		const char const	options
	)

Get a WKT representation of an object.

The lifetime of the returned string is the same as the input obj parameter.

This function calls osgeo::proj::io::IWKTExportable::exportToWKT().

This function may return NULL if the object is not compatible with an export to the requested type.

Parameters

obj	Object (must not be NULL)
type	WKT version.
options	should be set to NULL for now

Returns: a string, or NULL in case of error.

PJ_OBJ* proj_obj_create_from_database	(	PJ_CONTEXT *	ctx,
		const char *	auth_name,
		const char *	code,
		PJ_OBJ_CATEGORY	category,
		int	usePROJAlternativeGridNames,
		const char const	options
	)

Instanciate an object from a database lookup.

The returned object must be unreferenced with proj_obj_unref() after use. It should be used by at most one thread at a time.

Parameters

ctx	Context, or NULL for default context.
auth_name	Authority name (must not be NULL)
code	Object code (must not be NULL)
category	Object category
usePROJAlternativeGridNames	Whether PROJ alternative grid names should be substituted to the official grid names. Only used on transformations
options	should be set to NULL for now

Returns: Object that must be unreferenced with proj_obj_unref(), or NULL in case of error.

PJ_OBJ* proj_obj_create_from_proj_string	(	PJ_CONTEXT *	ctx,
		const char *	proj_string
	)

Instanciate an object from a PROJ string.

This function calls osgeo::proj::io::PROJStringParser::createFromPROJString()

The returned object must be unreferenced with proj_obj_unref() after use. It should be used by at most one thread at a time.

Parameters

ctx	PROJ context, or NULL for default context
proj_string	PROJ string (must not be NULL)

Returns: Object that must be unreferenced with proj_obj_unref(), or NULL in case of error.

PJ_OBJ* proj_obj_create_from_user_input	(	PJ_CONTEXT *	ctx,
		const char *	text
	)

Instanciate an object from a WKT string, PROJ string or object code (like "EPSG:4326", "urn:ogc:def:crs:EPSG::4326", "urn:ogc:def:coordinateOperation:EPSG::1671").

This function calls osgeo::proj::io::createFromUserInput()

The returned object must be unreferenced with proj_obj_unref() after use. It should be used by at most one thread at a time.

Parameters

ctx	PROJ context, or NULL for default context
text	String (must not be NULL)

Returns: Object that must be unreferenced with proj_obj_unref(), or NULL in case of error.

PJ_OBJ* proj_obj_create_from_wkt	(	PJ_CONTEXT *	ctx,
		const char *	wkt
	)

Instanciate an object from a WKT string.

This function calls osgeo::proj::io::WKTParser::createFromWKT()

The returned object must be unreferenced with proj_obj_unref() after use. It should be used by at most one thread at a time.

Parameters

ctx	PROJ context, or NULL for default context
wkt	WKT string (must not be NULL)

Returns: Object that must be unreferenced with proj_obj_unref(), or NULL in case of error.

PJ_OPERATION_RESULT* proj_obj_create_operations	(	PJ_OBJ *	source_crs,
		PJ_OBJ *	target_crs,
		PJ_OPERATION_FACTORY_CONTEXT *	operationContext
	)

Find a list of CoordinateOperation from source_crs to target_crs.

The operations are sorted with the most relevant ones first: by descending area (intersection of the transformation area with the area of interest, or intersection of the transformation with the area of use of the CRS), and by increasing accuracy. Operations with unknown accuracy are sorted last, whatever their area.

Parameters

source_crs	source CRS. Must not be NULL.
target_crs	source CRS. Must not be NULL.
operationContext	Search context. Must not be NULL.

Returns: a result set that must be unreferenced with proj_operation_result_unref(), or NULL in case of error.

PJ_OBJ* proj_obj_crs_create_bound_crs_to_WGS84 ( PJ_OBJ * crs )

Returns potentially a BoundCRS, with a transformation to EPSG:4326, wrapping this CRS.

The returned object must be unreferenced with proj_obj_unref() after use. It should be used by at most one thread at a time.

This is the same as method osgeo::proj::crs::CRS::createBoundCRSToWGS84IfPossible()

Parameters

crs	Objet of type CRS (must not be NULL)

Returns: Object that must be unreferenced with proj_obj_unref(), or NULL in case of error.

PJ_OBJ* proj_obj_crs_get_coordoperation	(	PJ_OBJ *	crs,
		const char **	pMethodName,
		const char **	pMethodAuthorityName,
		const char **	pMethodCode
	)

Return the Conversion of a DerivedCRS (such as a ProjectedCRS), or the Transformation from the baseCRS to the hubCRS of a BoundCRS.

The returned object must be unreferenced with proj_obj_unref() after use. It should be used by at most one thread at a time.

Parameters

crs	Objet of type DerivedCRS or BoundCRSs (must not be NULL)
pMethodName	Pointer to a string value to store the method (projection) name. or NULL
pMethodAuthorityName	Pointer to a string value to store the method authority name. or NULL
pMethodCode	Pointer to a string value to store the method code. or NULL

Returns: Object of type SingleOperation that must be unreferenced with proj_obj_unref(), or NULL in case of error.

PJ_OBJ* proj_obj_crs_get_geodetic_crs ( PJ_OBJ * crs )

Get the geodeticCRS / geographicCRS from a CRS.

The returned object must be unreferenced with proj_obj_unref() after use. It should be used by at most one thread at a time.

Parameters

crs	Objet of type CRS (must not be NULL)

Returns: Object that must be unreferenced with proj_obj_unref(), or NULL in case of error.

PJ_OBJ* proj_obj_crs_get_horizontal_datum ( PJ_OBJ * crs )

Get the horizontal datum from a CRS.

The returned object must be unreferenced with proj_obj_unref() after use. It should be used by at most one thread at a time.

Parameters

crs	Objet of type CRS (must not be NULL)

Returns: Object that must be unreferenced with proj_obj_unref(), or NULL in case of error.

PJ_OBJ* proj_obj_crs_get_sub_crs	(	PJ_OBJ *	crs,
		int	index
	)

Get a CRS component from a CompoundCRS.

The returned object must be unreferenced with proj_obj_unref() after use. It should be used by at most one thread at a time.

Parameters

crs	Objet of type CRS (must not be NULL)
index	Index of the CRS component (typically 0 = horizontal, 1 = vertical)

Returns: Object that must be unreferenced with proj_obj_unref(), or NULL in case of error.

int proj_obj_ellipsoid_get_parameters	(	PJ_OBJ *	ellipsoid,
		double *	pSemiMajorMetre,
		double *	pSemiMinorMetre,
		int *	pIsSemiMinorComputed,
		double *	pInverseFlattening
	)

Return ellipsoid parameters.

Parameters

ellipsoid	Object of type Ellipsoid (must not be NULL)
pSemiMajorMetre	Pointer to a value to store the semi-major axis in metre. or NULL
pSemiMinorMetre	Pointer to a value to store the semi-minor axis in metre. or NULL
pIsSemiMinorComputed	Pointer to a boolean value to indicate if the semi-minor value was computed. If FALSE, its value comes from the definition. or NULL
pInverseFlattening	Pointer to a value to store the inverse flattening. or NULL

Returns: TRUE in case of success.

PJ_OBJ* proj_obj_get_ellipsoid ( PJ_OBJ * obj )

Get the ellipsoid from a CRS or a GeodeticReferenceFrame.

The returned object must be unreferenced with proj_obj_unref() after use. It should be used by at most one thread at a time.

Parameters

obj	Objet of type CRS or GeodeticReferenceFrame (must not be NULL)

Returns: Object that must be unreferenced with proj_obj_unref(), or NULL in case of error.

const char* proj_obj_get_id_auth_name	(	PJ_OBJ *	obj,
		int	index
	)

Get the authority name / codespace of an identifier of an object.

The lifetime of the returned string is the same as the input obj parameter.

Parameters

obj	Object (must not be NULL)
index	Index of the identifier. 0 = first identifier

Returns: a string, or NULL in case of error or missing name.

const char* proj_obj_get_id_code	(	PJ_OBJ *	obj,
		int	index
	)

Get the code of an identifier of an object.

The lifetime of the returned string is the same as the input obj parameter.

Parameters

obj	Object (must not be NULL)
index	Index of the identifier. 0 = first identifier

Returns: a string, or NULL in case of error or missing name.

const char* proj_obj_get_name ( PJ_OBJ * obj )

Get the name of an object.

The lifetime of the returned string is the same as the input obj parameter.

Parameters

obj	Object (must not be NULL)

Returns: a string, or NULL in case of error or missing name.

PJ_OBJ* proj_obj_get_prime_meridian ( PJ_OBJ * obj )

Get the prime meridian of a CRS or a GeodeticReferenceFrame.

The returned object must be unreferenced with proj_obj_unref() after use. It should be used by at most one thread at a time.

Parameters

obj	Objet of type CRS or GeodeticReferenceFrame (must not be NULL)

Returns: Object that must be unreferenced with proj_obj_unref(), or NULL in case of error.

PJ_OBJ* proj_obj_get_source_crs ( PJ_OBJ * obj )

Return the base CRS of a BoundCRS or the source CRS of a CoordinateOperation.

The returned object must be unreferenced with proj_obj_unref() after use. It should be used by at most one thread at a time.

Parameters

obj	Objet of type BoundCRS or CoordinateOperation (must not be NULL)

Returns: Object that must be unreferenced with proj_obj_unref(), or NULL in case of error, or missing source CRS.

PJ_OBJ* proj_obj_get_target_crs ( PJ_OBJ * obj )

Return the hub CRS of a BoundCRS or the target CRS of a CoordinateOperation.

The returned object must be unreferenced with proj_obj_unref() after use. It should be used by at most one thread at a time.

Parameters

obj	Objet of type BoundCRS or CoordinateOperation (must not be NULL)

Returns: Object that must be unreferenced with proj_obj_unref(), or NULL in case of error, or missing target CRS.

PJ_OBJ_TYPE proj_obj_get_type ( PJ_OBJ * obj )

Return the type of an object.

Parameters

obj	Object (must not be NULL)

Returns: its type.

int proj_obj_is_crs ( PJ_OBJ * obj )

Return whether an object is a CRS.

Parameters

obj	Object (must not be NULL)

int proj_obj_prime_meridian_get_parameters	(	PJ_OBJ *	prime_meridian,
		double *	pLongitude,
		double *	pLongitudeUnitConvFactor,
		const char **	pLongitudeUnitName
	)

Return prime meridian parameters.

Parameters

prime_meridian	Object of type PrimeMeridian (must not be NULL)
pLongitude	Pointer to a value to store the longitude of the prime meridian, in its native unit. or NULL
pLongitudeUnitConvFactor	Pointer to a value to store the conversion factor of the prime meridian longitude unit to radian. or NULL
pLongitudeUnitName	Pointer to a string value to store the unit name. or NULL

Returns: TRUE in case of success.

void proj_obj_unref ( PJ_OBJ * obj )

Drops a reference on an object.

This method should be called one and exactly one for each function returning a PJ_OBJ*

Parameters

obj	Object, or NULL.

void proj_operation_factory_context_set_allow_use_intermediate_crs	(	PJ_OPERATION_FACTORY_CONTEXT *	ctxt,
		int	allow
	)

Set whether an intermediate pivot CRS can be used for researching coordinate operations between a source and target CRS.

Concretely if in the database there is an operation from A to C (or C to A), and another one from C to B (or B to C), but no direct operation between A and B, setting this parameter to true, allow chaining both operations.

The current implementation is limited to researching one intermediate step.

By default, all potential C candidates will be used. proj_operation_factory_context_set_allowed_intermediate_crs() can be used to restrict them.

The default is true.

Parameters

ctxt	Operation factory context. must not be NULL
allow	whether intermediate CRS may be used.

void proj_operation_factory_context_set_allowed_intermediate_crs	(	PJ_OPERATION_FACTORY_CONTEXT *	ctxt,
		const char const	list_of_auth_name_codes
	)

Restrict the potential pivot CRSs that can be used when trying to build a coordinate operation between two CRS that have no direct operation.

Parameters

ctxt	Operation factory context. must not be NULL
list_of_auth_name_codes	an array of strings NLL terminated, with the format { "auth_name1", "code1", "auth_name2", "code2", ... NULL }

void proj_operation_factory_context_set_area_of_interest	(	PJ_OPERATION_FACTORY_CONTEXT *	ctxt,
		double	west_lon,
		double	south_lat,
		double	east_lon,
		double	north_lat
	)

Set the desired area of interest for the resulting coordinate transformations.

For an area of interest crossing the anti-meridian, west_lon will be greater than east_lon.

Parameters

ctxt	Operation factory context. must not be NULL
west_lon	West longitude (in degrees).
south_lat	South latitude (in degrees).
east_lon	East longitude (in degrees).
north_lat	North latitude (in degrees).

void proj_operation_factory_context_set_crs_extent_use	(	PJ_OPERATION_FACTORY_CONTEXT *	ctxt,
		PROJ_CRS_EXTENT_USE	use
	)

Set how source and target CRS extent should be used when considering if a transformation can be used (only takes effect if no area of interest is explicitly defined).

The default is PJ_CRS_EXTENT_SMALLEST.

Parameters

ctxt	Operation factory context. must not be NULL
use	How source and target CRS extent should be used.

void proj_operation_factory_context_set_desired_accuracy	(	PJ_OPERATION_FACTORY_CONTEXT *	ctxt,
		double	accuracy
	)

Set the desired accuracy of the resulting coordinate transformations.

Parameters

ctxt	Operation factory context. must not be NULL
accuracy	Accuracy in meter (or 0 to disable the filter).

void proj_operation_factory_context_set_grid_availability_use	(	PJ_OPERATION_FACTORY_CONTEXT *	ctxt,
		PROJ_GRID_AVAILABILITY_USE	use
	)

Set how grid availability is used.

The default is USE_FOR_SORTING.

Parameters

ctxt	Operation factory context. must not be NULL
use	how grid availability is used.

void proj_operation_factory_context_set_spatial_criterion	(	PJ_OPERATION_FACTORY_CONTEXT *	ctxt,
		PROJ_SPATIAL_CRITERION	criterion
	)

Set the spatial criterion to use when comparing the area of validity of coordinate operations with the area of interest / area of validity of source and target CRS.

The default is PROJ_SPATIAL_CRITERION_STRICT_CONTAINMENT.

Parameters

ctxt	Operation factory context. must not be NULL
criterion	patial criterion to use

void proj_operation_factory_context_set_use_proj_alternative_grid_names	(	PJ_OPERATION_FACTORY_CONTEXT *	ctxt,
		int	usePROJNames
	)

Set whether PROJ alternative grid names should be substituted to the official authority names.

The default is true.

Parameters

ctxt	Operation factory context. must not be NULL
usePROJNames	whether PROJ alternative grid names should be used

void proj_operation_factory_context_unref ( PJ_OPERATION_FACTORY_CONTEXT * ctxt )

Drops a reference on an object.

This method should be called one and exactly one for each function returning a PJ_OPERATION_FACTORY_CONTEXT*

Parameters

ctxt	Object, or NULL.

PJ_OBJ* proj_operation_result_get	(	PJ_OPERATION_RESULT *	result,
		int	index
	)

Return a CoordinateOperation in the result set.

The returned object must be unreferenced with proj_obj_unref() after use. It should be used by at most one thread at a time.

Parameters

result	Objet of type PJ_OPERATION_RESULT (must not be NULL)
index	Index

Returns: a new object that must be unreferenced with proj_obj_unref(), or nullptr in case of error.

int proj_operation_result_get_count ( PJ_OPERATION_RESULT * result )

Return the number of CoordinateOperation in the result set.

Parameters

result Objet of type PJ_OPERATION_RESULT (must not be NULL)

void proj_operation_result_unref ( PJ_OPERATION_RESULT * result )

Drops a reference on an object.

This method should be called one and exactly one for each function returning a PJ_OPERATION_RESULT*

Parameters

result Object, or NULL.

Typedefs

Enumerations

Functions

Detailed Description

Enumeration Type Documentation

Function Documentation