> > > As far as I can tell, this is a mis-understanding. The > > > value "0.325" applies to radio waves. Visible light is > > > very close to 1:7. > > > > What if I am interested in radio waves, not visible light, > > e.g. for antenna relay positions? IMHO, that refraction > > coefficient should not be hard-coded. > > Agreed. It's a settable value in r.ecurv.comp and should > also be one in all GRASS modules that have refraction > compensation.
ok good point, wavelength matters & VHF LOS propagation distance is an important problem to model. r.viewshed now has a user settable refection coefficient in the range 0.0-1.0. coeff=0.0 is like no refraction, 1.0 totally cancels out any curvature of the Earth. btw 1/7 is not 0.13, it's ~0.143. (to be picky) Hamish _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
