CoordOp.Type

Description

Name

enum Tinman.Georef.CoordOp.Type

Used by

CoordOp.method

Enumeration of horizontal map projection/transformation methods.

Items

# Name Tag

0

none

-

No horizontal map projection, i.e. latitude and longitude angles are used as map coordinates.

1

Albers

-

Albers (conic, equal-area)

These parameters are defined for this transform:

The following coordinate operation methods are mapped to this transform factory:

  • EPSG-9820: Lambert Azimuthal Equal Area

  • GeoTIFF-11: CT_AlbersEqualArea

  • OpenGIS WKT1: "Albers_Conic_Equal_Area"

  • PROJ: +proj=aea

2

Cassini

-

Cassini-Soldner (cylindrical)

These parameters are defined for this transform:

The following coordinate operation methods are mapped to this transform factory:

  • EPSG-9806: Cassini-Soldner

  • GeoTIFF-18: CT_CassiniSoldner

  • OpenGIS WKT1: "Cassini_Soldner"

  • PROJ: +proj=cass

3

Cubemap_Face

-

Maps geographic coordinates (latitude, longitude) onto a cubemap face.

Map coordinates (easting, northing) are mapped to cubemap face coordinates as follows:

map(-r, -r) => face(0, 0);
map( r, -r) => face(n, 0);
map(-r,  r) => face(0, n);
map( r,  r) => face(n, n);

where n is the cubemap size minus one and r is the radius of the reference sphere.

These parameters are defined for this transform:

The latitude and longitude parameters are only used to choose the cubemap face.

4

Equirectangular

-

Equidistant (cylindrical)

These parameters are defined for this transform:

The following coordinate operation methods are mapped to this transform factory:

  • EPSG-1028: Equidistant Cylindrical

  • GeoTIFF-17: CT_Equirectangular

  • OpenGIS WKT1: "Equirectangular"

  • PROJ: +proj=eqc

When CoordOp.latitude is set for this method, the value is applied to CoordOp.parallel1 instead.

5

Lambert_Azimuthal

-

Lambert (azimuthal, equal-area)

These parameters are defined for this transform:

The following coordinate operation methods are mapped to this transform factory:

  • EPSG-9820: Lambert Azimuthal Equal Area

  • GeoTIFF-10: CT_LambertAzimEqualArea

  • OpenGIS WKT1: "Lambert_Azimuthal_Equal_Area"

  • PROJ: +proj=laea

6

Lambert_Conic

-

Lambert (conic, conformal)

These parameters are defined for this transform:

For the 1SP variant:

For the 2SP variant:

The following coordinate operation methods are mapped to this transform factory:

  • PROJ: +proj=lcc

For the 1SP variant:

  • EPSG-9801: Lambert Conic Conformal (1SP).

  • GeoTIFF-9: CT_LambertConfConic_Helmert

  • OpenGIS WKT1: "Lambert_Conformal_Conic_1SP"

For the 2SP variant:

  • EPSG-9802: Lambert Conic Conformal (2SP)

  • GeoTIFF-8: CT_LambertConfConic_2SP

  • OpenGIS WKT1: "Lambert_Conformal_Conic_2SP"

7

Lambert_Cylindrical

-

Lambert (cylindrical, equal-area)

These parameters are defined for this transform:

The following coordinate operation methods are mapped to this transform factory:

  • EPSG-9835: Lambert Cylindrical Equal Area

  • GeoTIFF-28: CT_CylindricalEqualArea

  • OpenGIS WKT1: "Cylindrical_Equal_Area"

  • PROJ: +proj=cea

When CoordOp.latitude is set for this method, the value is applied to CoordOp.parallel1 instead.

8

Mercator

-

Mercator (cylindrical, conformal)

These parameters are defined for this transform:

For the A variant:

For the B variant:

The following coordinate operation methods are mapped to this transform factory:

  • GeoTIFF-7: CT_Mercator

  • PROJ: +proj=merc

For the A variant:

  • EPSG-9804: Mercator (variant A)

  • OpenGIS WKT1: "Mercator_1SP"

For the B variant:

  • EPSG-9805: Mercator (variant B)

  • OpenGIS WKT1: "Mercator_2SP"

9

Oblique_Mercator_A

-

Oblique Mercator (cylindrical, conformal)

These parameters are defined for this transform:

The following coordinate operation methods are mapped to this transform factory:

  • EPSG-9812: Hotine Oblique Mercator (variant A)

  • GeoTIFF-3: CT_ObliqueMercator

  • OpenGIS WKT1: "Hotine_Oblique_Mercator"

  • PROJ: +proj=omerc

10

Oblique_Mercator_B

-

Oblique Mercator (cylindrical, conformal)

These parameters are defined for this transform:

The following coordinate operation methods are mapped to this transform factory:

  • EPSG-9815: Hotine Oblique Mercator (variant B)

  • GeoTIFF-9815: CT_HotineObliqueMercatorAzimuthCenter

  • OpenGIS WKT1: "Hotine_Oblique_Mercator_Azimuth_Center"

  • PROJ: +proj=omerc

11

Oblique_Stereographic

-

Oblique Stereographic (azimuthal, conformal)

These parameters are defined for this transform:

The following coordinate operation methods are mapped to this transform factory:

  • EPSG-9809: Oblique Stereographic

  • GeoTIFF-14: CT_Stereographic

  • GeoTIFF-16: CT_ObliqueStereographic

  • OpenGIS WKT1: "Stereographic"

  • OpenGIS WKT1: "Oblique_Stereographic"

  • PROJ: +proj=sterea

12

Polar_Stereographic

-

Polar Stereographic (azimuthal, conformal)

These parameters are defined for this transform:

For the variant A:

The following coordinate operation methods are mapped to this transform factory:

  • GeoTIFF-15: CT_PolarStereographic

  • OpenGIS WKT1: "Polar_Stereographic"

  • PROJ: +proj=stere

For the variant A:

  • EPSG-9810: Polar Stereographic (variant A)

For the variant B:

  • EPSG-9829: Polar Stereographic (variant B)

13

Popular_Mercator

-

Popular Visualization Pseudo Mercator

These parameters are defined for this transform:

The following coordinate operation methods are mapped to this transform factory:

  • EPSG-1024: Popular Visualization Pseudo Mercator

  • OpenGIS WKT1: "Mercator_Auxiliary_Sphere"

14

Sinusoidal

-

Sinusoidal (pseudo-cylindrical, equal-area)

These parameters are defined for this transform:

The following coordinate operation methods are mapped to this transform factory:

  • GeoTIFF-24: CT_Sinusoidal

  • OpenGIS WKT1: "Sinusoidal"

  • PROJ: +proj=sinu

15

TOAST

-

TOAST (Tessellated Octahedral Adaptive Subdivision Transform)
https://docs.worldwidetelescope.org/data-guide/1/spherical-projections/toast-projection

The following figure illustrates the mapping that is established by this coordinate operation:

(A)-----(B)-----(C)
 |      /|\      |       |   X  |   Y  |  LAT | LON-1 | LON-2 |
 |     / | \     |    ---+------+------+------+-------+-------+
 |    /  |  \    |     A | -90° |  90° | 90°S |   -   |   -   |
 |  (D)  |  (E)  |     B |   0° |  90° |  0°  |  90°E |  90°W |
 |  /    |    \  |     C |  90° |  90° | 90°S |   -   |   -   |
 | /     |     \ |     D | -45° |  45° |  0°  | 135°E |  45°W |
 |/      |      \|     E |  45° |  45° |  0°  |  45°E | 135°W |
(F)-----(G)-----(H)    F | -90° |   0° |  0°  | 180°  |   0°  |
 |\      |      /|     G |   0° |   0° | 90°N |   -   |   -   |
 | \     |     / |     H |  90° |   0° |  0°  |   0°  | 180°  |
 |  \    |    /  |     I | -45° | -45° |  0°  | 135°W |  45°E |
 |  (I)  |  (J)  |     J |  45° | -45° |  0°  |  45°W | 135°E |
 |    \  |  /    |     K | -90° | -90° | 90°S |   -   |   -   |
 |     \ | /     |     L |   0° | -90° |  0°  |  90°W |  90°E |
 |      \|/      |     M |  90° | -90° | 90°S |  45°W | 135°E |
(K)-----(L)-----(M)

X: Easting, Y: Northing, LAT := Latitude
LON-1: Longitude (inside), LON-2: Longitude (outside)

These parameters are defined for this transform:

The sign of the CoordOp.scale parameters chooses between the inside and outside projections:

The floor of the absolute value of the CoordOp.scale parameter chooses the projection variant:

  • 0 : linear interpolation, according to the figure above.

  • 1 : spherical interpolation using the base octahedron.

  • n : spherical interpolation using the (n-1)-th octahedron subdivision.

Commonly used subdivision levels are 0 (e.g. Hallo Northern SKY planetarium program) and 6 (e.g. WorldWide Telescope). The maximum value for n is 8; larger values will be clamped.

16

Transverse_Mercator

-

Transverse Mercator (cylindrical, conformal)

These parameters are defined for this transform:

The following coordinate operation methods are mapped to this transform factory:

  • EPSG-9807: Transverse Mercator

  • GeoTIFF-1: CT_TransverseMercator

  • OpenGIS WKT1: "Transverse_Mercator"

  • PROJ: +proj=tmerc

17

Transverse_Mercator_South

-

Transverse Mercator South Oriented (cylindrical, conformal)

These parameters are defined for this transform:

The following coordinate operation methods are mapped to this transform factory:

  • EPSG-9808: Transverse Mercator (South Oriented)

  • GeoTIFF-27: CT_TransvMercator_SouthOriented

  • OpenGIS WKT1: "Transverse_Mercator_South_Orientated"