[QGIS-Developer] QGIS 3.8 Transformations dialog

Nyall Dawson nyall.dawson at gmail.com
Sun Jun 30 18:11:08 PDT 2019


On Fri, 28 Jun 2019 at 17:29, Nyall Dawson <nyall.dawson at gmail.com> wrote:
>
> On Fri, 28 Jun 2019 at 17:11, Richard Duivenvoorde <rdmailings at duif.net> wrote:
> >
> > On 28/06/2019 01.28, Nyall Dawson wrote:
> > >> That one shows 'just' 2 options (added to the qgis.nl post)
> > >> IF the green line is just the first one, but we are not sure if it is
> > >> the right one... should we make it green anyway?
> >
> > > Ah, on proj 6 builds, we ARE sure that the first/green one is the most
> > > recommended one :) That's because proj gives us an ordered list of
> > > possible operations in order of preference (calculated using all
> > > proj's internal smarts and knowledge about the accuracy of different
> > > transform operations).
> >
> > Mmm, then my last question, after this I'll move to proj ;-)
> >
> > See:
> >
> > http://www.qgis.nl/media/2019/06/Screenshot-20190627104509-716x467.png
> >
> > This is QGIS with proj6: As you see there are 2 options. The first one
> > being green 'numbered' (3). But the bottom one having a higher number
> > between brackets having a (4) between brackets?
> >
> > Now /me wondering what these numbers are: because given your answer
> > above, the green one being 'THE one' :-) I wonder what this other
> > numbers are (I was wondering ordered by date/relevance or so)??
>
> These are how proj identifies the coordinate operation -- I'm not
> entirely sure what they represent, but I assume they are just indexes.

Just for followers of this thread - conversation moved to the proj
mailing list, and looks like it will result in improved descriptive
strings coming as a result...
Nyall


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