On Tuesday 26 August 2008, Markus Neteler wrote: > On Tue, Aug 26, 2008 at 3:10 PM, Glynn Clements > > <[EMAIL PROTECTED]> wrote: > > Markus Neteler wrote: > >> I try to understand an issue mentioned on grass-user but get only > >> enigmatic error messages: > >> > >> v.extrude -t bldg_cmcl out=bldg_cmcl_3d height=15 > >> elev=el_D792_6m --o > >> WARNING: Vector map <bldg_cmcl_3d> already exists and will be > >> overwritten > >> > >> WARNING: Reading raster map <[EMAIL PROTECTED]> request for row > >> 220803 is outside region > >> ERROR: Problem reading raster map > > ... > > > Any warning generated there is useless to the end user, as it > > indicates a bug in the code. It's the caller's responsibility to avoid > > requesting rows which lie outside the current region. > > > > > > I've committed fixes to a number of bugs in G_get_raster_sample(). > > Apart from trying to read invalid rows, it was deliberately reading > > the wrong rows at the edge of the region, and pretending that nulls > > were zero (they aren't; just because you would like a definite (i.e. > > non-null) answer, that doesn't mean that you can have one). > > I have backported this. > > > I've also fixed v.sample to deal with the fact that the result may be > > null. > > v.extrude and v.drape also use that function, so they may need similar > > changes.
Not able to comment on the patch, but I can confirm that v.drape uses G_get_raster_sample() in GRASS64. v.drape tests for vector input features lying outside of the current region / extent of the input raster... However I don't think that it is currently done in a very robust way. Also, if the input vector is not contained within the input raster / current region a warning is raised and a 0 is written to the z coordinate. Perhaps a different behavior would be more robust. Ideas? Cheers, Dylan -- Dylan Beaudette Soil Resource Laboratory http://casoilresource.lawr.ucdavis.edu/ University of California at Davis 530.754.7341 _______________________________________________ grass-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-dev
