[SoC] Re: [GRASS-dev] SoC Report: v.buffer/v.parallel reimplementation

[Hamish]

Hi,

I know it is very much a work in progress, but some minor comments/suggestions.

http://trac.osgeo.org/grass/changeset/31708

v.parallel2/main.c
-side_opt->options = "left,right";
+side_opt->options = "both,left,right";
?

v.parallel2/vlib_buffer.c
+#define LENGTH(DX, DY) (sqrt((DX*DX)+(DY*DY)))

why not use hypot() ? There are vector library versions too, for both Cartesian and lat/lon. Vect_line_length(), Vect_line_geodesic_length() and the rest in lib/vector/Vlib/line.c
Vect_line_geodesic_length() will switch to hypot if location is not lat/lon, otherwise it uses the great circle calc.

any thoughts in general on how to deal with parallel lines in lat/lon? I would guess to make them parallel "on the ground" rather than as simple parallel rhumblines.

3D?


+G_message("tol=%f atol=%f", tol, angular_tol);
I would recommend making good use of G_debug() there. You can set the level to "0" to always show the message when developing then adjust that to something higher later on.


that's all,
Hamish