# GTIFDefn Struct Reference

`#include <geo_normalize.h>`

List of all members.

## Public Attributes

short | Model
short | PCS
short | GCS
short | UOMLength
double | UOMLengthInMeters
short | UOMAngle
double | UOMAngleInDegrees
short | Datum
short | PM
double | PMLongToGreenwich
short | Ellipsoid
double | SemiMajor
double | SemiMinor
short | TOWGS84Count
double | TOWGS84 [7]
short | ProjCode
short | Projection
short | CTProjection
int | nParms
double | ProjParm [MAX_GTIF_PROJPARMS]
int | ProjParmId [MAX_GTIF_PROJPARMS]
int | MapSys
int | Zone
int | DefnSet

## Detailed Description

Holds a definition of a coordinate system in normalized form.

## Member Data Documentation

short GTIFDefn::CTProjection

GeoTIFF identifier for underlying projection method. While some of these values have corresponding vlaues in EPSG (Projection field), others do not. For example CT_TransverseMercator.

short GTIFDefn::Datum

Datum from GeogGeodeticDatumGeoKey tag. For example Datum_WGS84

int GTIFDefn::DefnSet

Do we have any definition at all? 0 if no geokeys found

short GTIFDefn::Ellipsoid

Ellipsoid identifier from GeogELlipsoidGeoKey. For example Ellipse_Clarke_1866.

short GTIFDefn::GCS

From GeographicTypeGeoKey tag. For example GCS_WGS_84 or GCS_Voirol_1875_Paris. Includes datum and prime meridian value.

int GTIFDefn::MapSys

Special zone map system code (MapSys_UTM_South, MapSys_UTM_North, MapSys_State_Plane or KvUserDefined if none apply.

short GTIFDefn::Model

From GTModelTypeGeoKey tag. Can have the values ModelTypeGeographic or ModelTypeProjected.

int GTIFDefn::nParms

Number of projection parameters in ProjParm and ProjParmId.

short GTIFDefn::PCS

From ProjectedCSTypeGeoKey tag. For example PCS_NAD27_UTM_zone_3N.

short GTIFDefn::PM

Prime meridian from GeogPrimeMeridianGeoKey. For example PM_Greenwich or PM_Paris.

double GTIFDefn::PMLongToGreenwich

Decimal degrees of longitude between this prime meridian and Greenwich. Prime meridians to the west of Greenwich are negative.

short GTIFDefn::ProjCode

Projection id from ProjectionGeoKey. For example Proj_UTM_11S.

short GTIFDefn::Projection

EPSG identifier for underlying projection method. From the EPSG TRF_METHOD table.

double GTIFDefn::ProjParm[MAX_GTIF_PROJPARMS]

Projection parameter value. The identify of this parameter is established from the corresponding entry in ProjParmId. The value will be measured in meters, or decimal degrees if it is a linear or angular measure.

int GTIFDefn::ProjParmId[MAX_GTIF_PROJPARMS]

Projection parameter identifier. For example ProjFalseEastingGeoKey. The value will be 0 for unused table entries.

double GTIFDefn::SemiMajor

The length of the semi major ellipse axis in meters.

double GTIFDefn::SemiMinor

The length of the semi minor ellipse axis in meters.

double GTIFDefn::TOWGS84[7]

TOWGS84 transformation values

short GTIFDefn::TOWGS84Count

TOWGS84 transformation values (0/3/7)

short GTIFDefn::UOMAngle

The angular units of the GCS.

double GTIFDefn::UOMAngleInDegrees

One UOMAngle = UOMLengthInDegrees degrees.

short GTIFDefn::UOMLength

From ProjLinearUnitsGeoKey. For example Linear_Meter.

double GTIFDefn::UOMLengthInMeters

One UOMLength = UOMLengthInMeters meters.

int GTIFDefn::Zone

UTM, or State Plane Zone number, zero if not known.

The documentation for this struct was generated from the following file:

- geo_normalize.h