Markus Metz

@agiudiceandrea @kbevers > > There is also the [Planimeter](https://geographiclib.sourceforge.io/html/Planimeter.1.html) tool of GeographicLib. > > Have you also used the "Planimeter" tool with the "-E" option? Same result. Does not answer...

> I'm on Debian testing. Is there any env variable I need to set or something ? Is there a way to test that I'm really using the GeographicLib ?...

This tiny test polygon with a size of about 0.1263 sqm seems to hit the limits of floating point calculations and trigonometric functions. For larger areas, the Planimeter tool of...

> > ``` > > "exact" area (m^2) = 251199344354.42985178 > > QGIS 3.17 with GRASS method = 249566957499.7546 > > ``` > > Using this PR (with PROJ 7.2.1)...

Thinking about it, I prefer to introduce new `GPJ_*()` functions in `lib/proj` instead of adding PROJ lib as a new dependency to `lib/gis`. Thus all library functions that depend on...

> I was wrong. Level 2 vector always requires topology building to remain level 2 even if there are no changes. Just tried this: > > ```c > Vect_open_update2(); >...

> Thanks for the PR. With that change, `Vect_close()` did the job, but `G_fatal_error()` still downgrades the level to 1 without an error handler (minor annoyance ;-). Should be fixed...

> This PR adds two examples into `doc/examples` which can be compiled as GRASS modules and executed. It adds 3 new sections to the library dox file: about general use...

Considering examples on how to use the segment library, it is IMHO sufficient to mention current working modules like r.cost, r.walk, r.watershed, r.stream.extract.

Do you have the grid files installed locally on your system? From https://proj.org/en/stable/resource_files.html > When networking capabilities are enabled, either by API with the [proj_context_set_enable_network()](https://proj.org/en/stable/development/reference/functions.html#c.proj_context_set_enable_network) function or when the [PROJ_NETWORK](https://proj.org/en/stable/usage/environmentvars.html#envvar-PROJ_NETWORK)...