Appendix C. Supported Projections

The following types of projections are directly support by Thuban. The specific values for each are provided by the user to create custom projections. Thuban comes with predefined projections which are available through the Projections dialog.

• Geographic

  • Ellipsoid

  • Source Data: either Degrees or Radians

• Lambert Conic Conformal

  • Ellipsoid

  • Latitude of 1st standard parallel

  • Latitude of 2nd standard parallel

  • Central Meridian

  • Latitude of Origin

  • False Easting (meters)

  • False Northing (meters)

• Transverse Mercator

  • Ellipsoid

  • Latitudeof origin

  • Longitudeat central meridian

  • Scale Factorat central meridian

  • False Easting (meters)

  • False Northing (meters)

• Universal Transverse Mercator

  • Ellipsoid

  • Zone (can be guessed appling the Propose button)

  • Southern Hemisphere flag

Thuban comes with a sample set of map projections for various European countries. Apart from the basic projection they differ especially in their parameterization:

• Belgium Datum 1972 (Lambert Conic Conformal)

• Gauss-Boaga Zone 1 (Italy, Transverse Mercartor)

• Gauss-Krueger Zone 2 (Germany, Transverse Mercartor)

• Reseau Geodesique Francaise (France, Lambert Conic Conformal)

• UK National Grid (United Kingdom, Transverse Mercartor)

Thuban uses the comprehensive PROJ library for projections. PROJ provides more than the four commonly used projections described above. If needed Thuban can be easily extended to a new projection covered by PROJ.