api:dk11:delphi:giscsprojections.tgis_csprojabstract
Table of Contents
TGIS_CSProjAbstract class
DK for Delphi | GisCsProjections.TGIS_CSProjAbstract | Classes | Constructors | Fields | Methods | Properties
Abstract base class for all map projection implementations.
Syntax
// Delphi type TGIS_CSProjAbstract = class( TGIS_CSAbstract ) end;
// C++ Builder class PASCALIMPLEMENTATION TGIS_CSProjAbstract : public TGIS_CSAbstract { };
Inheritance
Constructors
Inherited
Overrides
Protected
Private
| Name | Visibility | Description | |
|---|---|---|---|
| Create | public | Creates an instance of the projection object with WGS84 datum and initializes projection parameters from EPSG code or WKT string. | |
Fields
Inherited
Protected
Private
| Name | Visibility | Description | |
|---|---|---|---|
| FDatum | protected | Property internal storage for datum reference. | |
| FDescription | protected | Property internal storage for projection description. | |
| FEllipsoid | protected | Property internal storage for ellipsoid reference. | |
| FError | protected | Property internal storage for error state. | |
| FIsEllipsoid | protected | Property internal storage: ellipsoid flag. | |
| FIsGrid | protected | Property internal storage: grid projection flag. | |
| FIsPureCylindrical | protected | Property internal storage: pure cylindrical flag. | |
| FIsRevertible | protected | Property internal storage: reversible flag. | |
| FIsSpheroid | protected | Property internal storage: spheroid flag. | |
| FIsXYZ | protected | Property internal storage: 3D coordinate flag. | |
| FParameters | protected | Property internal storage. | |
| FParametersSet | protected | Property internal storage for supported parameters set. | |
| FSubtype | protected | Property internal storage for projection subtype. | |
| FValidityExtentWGS | protected | Property internal storage for WGS84 validity extent. | |
| FValidityOriginWGS | protected | Property internal storage for WGS84 validity origin point. | |
Methods
Inherited
Overrides
Protected
Private
| Name | Visibility | Description | |
|---|---|---|---|
| Assign | public | Copies the shared definition fields from another object. (Inherited from TGIS_CSAbstract) |
|
| CreateCopy | public | Creates a deep copy of this projection instance with all parameters and settings duplicated. | |
| datumChanged | protected | Procedure will be called upon any datum change. | |
| MarkDeprecated | public | Marks this coordinate system definition as deprecated or current. (Inherited from TGIS_CSAbstract) |
|
| Project | public | Transforms a single geodetic longitude/latitude point to projected easting/northing coordinates. | |
| Project3D | public | Transforms a single geodetic longitude/latitude/elevation point to projected coordinates. | |
| Project3D_Ref | public | Transform geodetic (latitude/longitude/elevation) coordinates to projected (easting/northing/elevation) in-place using current ellipsoid and projection parameters. | |
| projectPost | protected | Finalizes coordinates after projection-specific code runs. | |
| projectPre | protected | Prepares coordinates for projection before projection-specific code runs. | |
| set_Validity(Double; Double; Double; Double) | protected | Sets the validity extent for the projection in radians. | |
| set_Validity(Double; Double; Double; Double; Double; Double) | protected | Sets the validity extent for the projection in radians. | |
| set_Validity(Double; Double; Double; Double; Double; Double; Double; Double) | protected | Sets the validity extent for the projection in radians. | |
| Unproject | public | Reverse-transforms a single projected easting/northing point to geodetic longitude/latitude coordinates. | |
| Unproject3D | public | Reverse-transforms a single projected easting/northing/elevation point to geodetic coordinates. | |
| Unproject3D_Ref | public | Reverse-transform projected (easting/northing/elevation) coordinates back to geodetic (latitude/longitude/elevation) in-place using current ellipsoid and projection parameters. | |
| unprojectPost | protected | Finalizes coordinates after inverse projection-specific code runs. | |
| unprojectPre | protected | Prepares coordinates for inverse projection before projection-specific code runs. | |
Properties
Inherited
Protected
Private
| Name | Visibility | Description | |
|---|---|---|---|
| Azimuth | public | Azimuth angle from north (for oblique projections). | |
| CentralMeridian | public | Central Meridian (longitude of origin) for this projection in radians. | |
| Custom1 | public | Custom parameter value 1 (projection-specific). | |
| Custom1Name | public | Custom parameter 1 name/label (projection-specific). | |
| Custom2 | public | Custom parameter value 2 (projection-specific). | |
| Custom2Name | public | Custom parameter 2 name/label (projection-specific). | |
| Custom3 | public | Custom parameter value 3 (projection-specific). | |
| Custom3Name | public | Custom parameter 3 name/label (projection-specific). | |
| Custom4 | public | Custom parameter value 4 (projection-specific). | |
| Custom4Name | public | Custom parameter 4 name/label (projection-specific). | |
| Custom5 | public | Custom parameter value 5 (projection-specific). | |
| Custom5Name | public | Custom parameter 5 name/label (projection-specific). | |
| Custom6 | public | Custom parameter value 6 (projection-specific). | |
| Custom6Name | public | Custom parameter 6 name/label (projection-specific). | |
| Datum | public | Geodetic datum used by this projection, defining the ellipsoid model and coordinate reference frame. | |
| Deprecated | public | Indicates whether this definition is deprecated. (Inherited from TGIS_CSAbstract) |
|
| Description | public | Additional textual description for this projection, if available. | |
| DescriptionEx | public | Descriptive name; for internal use of TGIS_CSAbstractListHelper. (Inherited from TGIS_CSAbstract) |
|
| Ellipsoid | public | The ellipsoid (Earth model) currently in use by this projection. | |
| EPSG | public | EPSG code. (Inherited from TGIS_CSAbstract) |
|
| Error | public | Projection error code from the last transformation attempt. | |
| FalseEasting | public | False Easting (X coordinate offset) in meters. | |
| FalseNorthing | public | False Northing (Y coordinate offset) in meters. | |
| FriendlyName | public | Friendly name constructed from the WKT name and EPSG code. (Inherited from TGIS_CSAbstract) |
|
| IsEllipsoid | public | Indicates whether the projection uses ellipsoidal formulas. | |
| IsGrid | public | Indicates whether this projection is grid-based and uses only shift and scale style transformations. | |
| IsPureCylindrical | public | Indicates whether the projection's graticule (coordinate grid) is purely cylindrical with parallel meridians and parallels. | |
| IsRevertible | public | Indicates whether this projection can be reversed (inverse transformation from projected to geodetic coordinates supported). | |
| IsSpheroid | public | Indicates whether the projection uses spheroidal formulas. | |
| IsStandard | public | Indicates whether this projection is standard (not grid, not XYZ, and revertible). | |
| IsXYZ | public | Indicates whether this projection is XYZ-based and uses 3D Cartesian coordinates. | |
| LatitudeOfCenter | public | Latitude of center for this projection in radians. | |
| LatitudeOfOrigin | public | Latitude of origin for this projection in radians. | |
| LatitudeOfPoint_1 | public | Latitude of first control point (for two-point projections). | |
| LatitudeOfPoint_2 | public | Latitude of second control point (for two-point projections). | |
| LongitudeOfCenter | public | Longitude of center for this projection in radians. | |
| LongitudeOfPoint_1 | public | Longitude of first control point (for two-point projections). | |
| LongitudeOfPoint_2 | public | Longitude of second control point (for two-point projections). | |
| MasterEPSG | public | EPSG code of the object for which the current object is an alias. (Inherited from TGIS_CSAbstract) |
|
| Parameters | public | Gets or sets all projection parameter values as a single record. | |
| ParametersSet | public | Set of projection parameters supported by this projection. | |
| PseudoStandardParallel_1 | public | Pseudo standard parallel for this projection in radians. | |
| ScaleFactor | public | Scale factor (uniform scale ratio) for this projection. | |
| StandardParallel_1 | public | First Standard parallel. | |
| StandardParallel_2 | public | Second Standard parallel. | |
| ValidityExtentWGS | public | Validity extent for this projection in WGS84 geographic coordinates, expressed in radians. | |
| ValidityOriginWGS | public | Origin point of the validity extent for this projection in WGS84 geographic coordinates, expressed in radians. | |
| WKT | public | WKT name. (Inherited from TGIS_CSAbstract) |
|
| XScale | public | X Scale (width) factor for affine transformation. | |
| XYPlaneRotation | public | Plane rotation angle for affine transformation. | |
| YScale | public | Y Scale (height) factor for affine transformation. | |
| Zone | public | Zone number for UTM (Universal Transverse Mercator) projection. | |
Remarks
PURPOSE: Provide a common framework for projection implementations that convert between geographic and projected coordinates.
BEHAVIOR: Defines the shared projection interface, stores datum, ellipsoid, supported parameters, and validity information, and leaves projection-specific calculations to derived classes.
CONSTRAINTS: This class is abstract and cannot be instantiated directly. Not all projection parameters apply to all projections, and reverse transformation is available only for reversible projections.
2026/07/11 00:22