[PROJ] proj_angular_input

[Even Rouault]

On samedi 16 février 2019 06:57:10 CET Paul Ramsey wrote:
> So, I create a PJ thusly:
> 
> pj = proj_create_crs_to_crs(NULL, "EPSG:4326", "EPSG:3005", NULL);
> 
> The from is clearly angular, the to is an albers projection in NAD83.
> 
> But
> 
> proj_angular_input(pj, PJ_FWD)
> 
> Does not return true?
> 
> Am I misunderstanding the meaning of proj_angular_input or of
> forward/backward?

Hum, I guess we have some confusion here about the semantics of 
proj_angular_input() and what the "new code" I added those months does.

proj_angular_input() returns true if the expected values are in radian, but 
the pipeline returned by your above proj_create_crs_to_crs() invokation is

+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert 
+xy_in=deg +xy_out=rad +step +proj=aea +lat_0=45 +lon_0=-126 +lat_1=50 
+lat_2=58.5 +x_0=1000000 +y_0=0 +ellps=GRS80

so it does the deg -> rad conversion, which causes the pipeline to not expect 
radians, and thus return false in proj_angular_input()

Kristian, any idea what we should do ? The doc mentions "Check if a operation 
expects angular input.", but we have code we really expect angular to mean 
radian, such as in the proj utility that uses is to to deg to rad conversions.

Even

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