Glynn Clements wrote: > > In any case, the specific purpose of r.grow.distance is: > > > > r.grow.distance generates a raster map representing the distance to > > the nearest non-null cell in the input map. > > It now has an additional function: to generate a raster map containing > the value of the nearest cell. > > >From this, it is possible to mimic the behaviour of r.grow, but > substantially faster, with e.g.: > > # equivalent to: r.grow input=$inmap output=$outmap radius=$radius > metric=$metric > temp=r.grow.tmp.$$ > r.grow.distance in=$inmap distance=$temp.dist value=$temp.near metric=$metric > r.mapcalc "$outmap = if($temp.dist < $radius,$temp.near,null())" > r.colors $outmap rast=$temp.near > g.remove rast=$temp.dist,$temp.near > > Whereas the worst-case time taken by r.grow is proportional to the > square of the buffer radius, the above is proportional only to the > area of the map, regardless of the buffer radius. > > I'll replace r.grow in 7.0 with a script along these lines.
Done. I've also fixed the spelling of "euclidean" in both r.grow and r.grow.distance, in 6.4 and 7.0. -- Glynn Clements <[EMAIL PROTECTED]> _______________________________________________ grass-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-dev
