[SIS-370] Improve CoordinateOperation WKT for axis changes and Molodensky parameters

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 0.7, 0.8, 1.0, 1.1, 1.2, 1.3, 1.4
• Fix Version/s: 1.5
• Component/s: Referencing
• Assignee: Martin Desruisseaux
• Reporter: Martin Desruisseaux
• Created: 27/Oct/17 12:10
• Updated: 23/Sep/23 10:31

Description

The Well Known Text (WKT) formatting of CoordinateOperation objects have the following shortcomings:

In the formatting of Molodensky Parameters, Semi-major axis length difference and Flattening difference parameters are wrongly set to NaN. Note that this issue happen only for CoordinateOperation WKT, not for MathTransform WKT.

Operation steps inserted for changing axis order are shown as affine transform, which is difficult to read for most users. The formatter should detect automatically when a matrix is square, of size 3×3 or 4×4 and having 1 value on anti-diagonal (except last row) and show instead one of the following operations:

• EPSG::15498 — axis order change (2D)
• EPSG::15499 — axis order change (geographic3D horizontal)