> I have a group of points (vertex of a polygon) and I'd like to link > them to obtain a polygon (vector) to transform it in a rast. > > Is it hard to make it? Simple, r.in.poly. See the help page for details: http://grass.ibiblio.org/gdp/html_grass5/html/r.in.poly.html or v.in.ascii if you really want a vector polygon. Hamish