libproj: simple check for area of use

[metzm]

This PR adds a simple check if reprojection would fall outside the intended area of use of the target CRS.

I would prefer to refuse reprojection in these extreme cases, but this might be too restrictive. If subsequent errors occur because reprojected coordinates are invalid, this can be changed accordingly to actually refuse reprojection which is the current behaviour, but without explanation why.

[wenzeslaus]

I have resolved the indentation-related conflicts here.

[neteler]

A test:
I reprojected an Indonesian vector map into the NC sample dataset and do not yet see the warning being triggered:

GRASS nc_spm_08_grass7/user1:grass_main > v.proj location=utm49S_32749 mapset=hutan_mulya input=hutan_mulya_box
Found 2 possible transformations
************************
Operation 1:
Description: Inverse of UTM zone 49S + Inverse of NAD83(HARN) to WGS 84 (3)
+ SPCS83 North Carolina zone (meters)

Area of use: United States (USA) - CONUS onshore - Alabama; Arizona;
Arkansas; California; Colorado; Connecticut; Delaware; Florida; Georgia;
Idaho; Illinois; Indiana; Iowa; Kansas; Kentucky; Louisiana; Maine;
Maryland; Massachusetts; Michigan; Minnesota; Mississippi; Missouri;
Montana; Nebraska; Nevada; New Hampshire; New Jersey; New Mexico; New York;
North Carolina; North Dakota; Ohio; Oklahoma; Oregon; Pennsylvania; Rhode
Island; South Carolina; South Dakota; Tennessee; Texas; Utah; Vermont;
Virginia; Washington; West Virginia; Wisconsin; Wyoming.

Accuracy within area of use: 1 m

PROJ string:
+proj=pipeline +step +inv +proj=utm +zone=49 +south +ellps=WGS84 +step
+proj=push +v_3 +step +proj=cart +ellps=WGS84 +step +inv +proj=helmert
+x=-0.991 +y=1.9072 +z=0.5129 +rx=-0.0257899075194932
+ry=-0.0096500989602704 +rz=-0.0116599432323421 +s=0
+convention=coordinate_frame +step +inv +proj=cart +ellps=GRS80 +step
+proj=pop +v_3 +step +proj=lcc +lat_0=33.75 +lon_0=-79
+lat_1=36.1666666666667 +lat_2=34.3333333333333 +x_0=609601.22 +y_0=0
+ellps=GRS80
************************
Operation 2:
Description: Inverse of UTM zone 49S + Inverse of NAD83(HARN) to WGS 84 (1)
+ SPCS83 North Carolina zone (meters)

Area of use: American Samoa - onshore - Tutuila, Aunu'u, Ofu, Olesega, Ta'u
and Rose islands. Guam - onshore. Northern Mariana Islands - onshore.
Puerto Rico - onshore. United States (USA) - onshore Alabama, Alaska,
Arizona, Arkansas, California, Colorado, Connecticut, Delaware, Florida,
Georgia, Hawaii, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky,
Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota,
Mississippi, Missouri, Montana, Nebraska, Nevada, New Hampshire, New
Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma,
Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota,
Tennessee, Texas, Utah, Vermont, Virginia, Washington, West Virginia,
Wisconsin and Wyoming; offshore Gulf of Mexico continental shelf (GoM OCS).
US Virgin Islands - onshore.

Accuracy within area of use: 2 m

PROJ string:
+proj=pipeline +step +inv +proj=utm +zone=49 +south +ellps=WGS84 +step
+proj=lcc +lat_0=33.75 +lon_0=-79 +lat_1=36.1666666666667
+lat_2=34.3333333333333 +x_0=609601.22 +y_0=0 +ellps=GRS80
************************
See also output of:
projinfo -o PROJ -s "EPSG:32749" -t "EPSG:3358"
Please provide the appropriate PROJ string with the pipeline option
************************
Selected PROJ pipeline:
+proj=pipeline +step +inv +proj=utm +zone=49 +south +ellps=WGS84 +step
+proj=lcc +lat_0=33.75 +lon_0=-79 +lat_1=36.1666666666667
+lat_2=34.3333333333333 +x_0=609601.22 +y_0=0 +ellps=GRS80
************************
Reprojecting primitives ...
Building topology for vector map <hutan_mulya_box@user1>...
Registering primitives...
Building areas...
 100%
Attaching islands...
 100%
Attaching centroids...
 100%

[neteler]

@metzm shall I bump this PR to 8.4.0?

[wenzeslaus]

When I imagine getting this message I think I would lack three pieces of information:

1. What region? Is that extent of my raster?
2. The actual numbers and what's wrong about them. This is what I did for g.region: g.region: Add more detail into error messages #1140 and g.region: Add more detail into LL error messages #1988 in lib/gis/adj_cellhd.c. This may also clarify the uncertainty expressed by "it seems to".
3. What will happen next. It's a warning, not error, so I would expect the code to go on which it does but it also does some adjustment to the values.

[metzm]

This test is not working as expected. PROJ has its own mechanism to check for the area of use with its spatial criterions PROJ_SPATIAL_CRITERION_STRICT_CONTAINMENT and PROJ_SPATIAL_CRITERION_PARTIAL_INTERSECTION, the latter is used by default in GDAL and GRASS.