Bug report #13957

Updated by Giovanni Manghi almost 7 years ago

In Project Properties, General, Ellipsoid - selecting some ellipsoids give huge values in Identify derived, both area and perimeter for polygons, and length for lines.



It appears that the transform does not initialize, according to the debug logger. However, the user is not informed of the failure.



Some ellipsoids that don't work: IGNF:ELG..., the various planet/moon names (not an exhaustive list)



I compared the list of ellipsoids in PROJ.4 (proj -le) to the list in tbl_ellipsoid and found by testing various ellipsoids that an ellipsoid in tbl_ellipsoid that does not have a PROJ.4 entry produces a transform initialization failure, therefore the very large area values. The user CRS that results shows +ellps= with the acronym from tbl_ellipsoid.



I have tried the user defined CRS (the projection shows longlat) that resulted from the ellipsoid choice as a project CRS (OTF on) and find that there appears to be no difference in the displayed map, aside from a very large Scale value displayed. A feature set that was in UTM most likely would have been stretched horizontally if the project CRS actually was transforming the geometries to longlat.



I am rating the priority as High because of the silent transform failure.

Back