[QGIS-Developer] How to get a generated CRS from an Unknown CRS

[René-Luc Dhont]

Hi devs,

We are facing a behavior we did not expect from QGIS Server regarding 
custom projections.

We are using Raster layer with a custom projection. This projection is 
well read and understanding by QGIS. The data are displayed at the right 
place with 'on-th-fly' CRS transformation. But the CRS is desribed by 
QGIS as an Unknown CRS and not as a Generated CRS.
In the XML project, the CRS is described with proj4 text and WKT but it 
does not have an authid with a USER authority.

And with QGIS Desktop and QGIS Server on Linux OS, sometimes the layer 
is loaded without any CRS. The layer properties dialog displayed an 
'invalid projection', even if the CRS is defined in the project and the 
layer has been well displyed before saving, closing and opening the project.

Here are my questions :
Is the auto generated CRS has been deactivated from QGIS ?
Is there a way to create a custom CRS from a layer CRS defined as 
unknown CRS ?

Regards,
René-Luc