libgis: define descriptions for G_OPT_R_INTERP_TYPE

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@56221 15284696-431f-4ddb-bdfa-cd5b030d7da7

lib/gis/parser_standard_options.c

@@ -307,8 +307,13 @@ struct Option *G_define_standard_option(int opt)
         Opt->key = "method";
         Opt->type = TYPE_STRING;
         Opt->required = NO;
-        Opt->description = _("Interpolation method");
+        Opt->description = _("Sampling interpolation method");
         Opt->options = "nearest,bilinear,bicubic";
+        G_asprintf((char **) &(Opt->descriptions),
+                   "nearest;%s;bilinear;%s;bicubic;%s",
+                   _("Nearest-neighbor interpolation"),
+                   _("Bilinear interpolation"),
+                   _("Bicubic interpolation"));
         break;
 
 	/*g3d maps */