[SIS-599] Robinson projection

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.5
• Component/s: Referencing
• Assignee: Martin Desruisseaux
• Reporter: Martin Desruisseaux
• Created: 30/Apr/24 12:26
• Updated: 03/May/24 10:39
• Resolved: 03/May/24 10:02

Description

Add support for the Robinson map projection. This projection is not described by EPSG guidance note, and I didn't not found it in Snyder's book neither. The only freely available reference that I found was Wikipedia, but that reference gives no details about the interpolation method. The non-free resources used for this task is:

Snyder, J. P. (1990). The Robinson projection: A computation algorithm. Cartography and Geographic Information Systems, 17 (4), p. 301-305.

The Snyder's article gives a program in the ANSI Fortran language. That program has been translated to Java in this class and adapted for SIS architecture (constants moved to normalization matrices). Robinson did not specify a particular interpolation method, but Snyder's program uses the Stirling's central-difference formula, while PROJ uses cubic splices. Some other software use Aitken interpolation. The Fortran program translated to Java did not converged well for the inverse projection of points near a pole (maybe it is the reason why PROJ uses cubic splines instead). We modified the algorithm with the use of derivative (∂y/∂φ) for faster convergence.