GMT (pscoast, psxy) connects line segments incorrectly

[Ulf Mehlig]

GMT pscoast and psxy connect line segments incorrectly. Example:

GMT pscoast -W1 -R-80/-30/-40/20 -JM10c -Gred > southamerica.ps

produces lines connecting points on the coastline or crossing the Amazon river.

Similarly, psxy plots files derived, e.g., from ogr2ogr (gdal) incorrectly:

GMT psxy -R-46.7528/-46.7370/-1.04990/-1.03850 -JM10c -m -W1,black,- < roads.gmt > roads.ps

(roads.gmt is derived from a OpenStreetMap postgresql/postgis database via ogr2ogr; endpoints of roads are in fact not connected by straight lines, as rendered by gmt).

The same problem occurred also in utopic (but not earlier, if I remember correctly).

If you need more details, please let me know.
Cheers, Ulf

[Marcelo Bianchi (m-tchelo)]

I also noticed that behaviour in debian 8.0. The psxy keeps on closing polygons even when the -L option is not given. Also, when I recompiled the gmt-4.5.12 supplied by debian (apt-get source) without applying the patches everything worked. This bug renders the package unusable.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Marcelo Bianchi (m-tchelo)]

If you remove the -ansi -fpedantic option from CFLAGS during compile in a DEBIAN 8.1 (gmt 4.5.12) the bug goes away. To test it:

% apt-get build-dep gmt
% apt-get source gmt
% cd gmt-4.5.12/
% vi debian/rules

Edit and remove the '-ansi -pedantic' from CFLAGS at line 3.

% fakeroot debian/rules binary

install the compiled package and it works for me.

I am not sure what does realy causes it but this is a hack solution that can lead to an answer.

Mb

[Bas Couwenberg (sebastic)]

This has been fixed in GMT 5, available in wily and later.