[GRASS-dev] Re: r.external

[Markus Neteler]

On Thu, Aug 21, 2008 at 1:54 PM, Markus Neteler <neteler at osgeo.org> wrote:
> On Thu, Aug 21, 2008 at 11:00 AM, Glynn Clements
> <glynn at gclements.plus.com> wrote:
>> Markus Neteler wrote:
>>
>>> >> Null support is missing (r.external records any null value reported by
>>> >> GDAL, but G_get_raster_row() etc ignore it; I suspect that it will
>>> >> treat zero as null due to the absence of a null file).
>>> >
>>> > Null support has been added.
>>>
>>> I have now tested (in my local 6.4 backport) a shaded terrain map (GeoTIFF).
>>> The 0 pixels are registered as NULL pixels, leading to white areas instead
>>> of black in case of cast terrain shadow.
>>>
>>> So I confirm that zero is treated as NULL now.
>>> Could the GDAL Null value be used instead?
>>
>> Null support was added in r32924, and seems to work.
>
> Ha - I missed to backport this one.
>
> Excellent, it now works fine in my local backport, too.


I found a problem with FP maps:

gdalinfo /tmp/geodata2_originals_raid5/pat_DTM_5m_derived_LIDAR_UTM_WGS84/pat_DTM_2008_derived_5m_UTM_WGS84.tif
..
Band 1 Block=23522x1 Type=Float32, ColorInterp=Gray
...

File size (if that matters): 2458610122

GRASS 7.0.svn (patUTM):~/grass70 > r.external
in=/tmp/geodata2_originals_raid5/pat_DTM_5m_derived_LIDAR_UTM_WGS84/pat_DTM_2008_derived_5m_UTM_WGS84.tif
out=pat_dtm_5m
Projection of input dataset and current location appear to match
<pat_dtm_5m> created
r.external complete.

GRASS 7.0.svn (patUTM):~/grass70 > d.rast pat_dtm_5m
PNG: GRASS_TRUECOLOR status: FALSE
PNG: collecting to file: map.png,
GRASS_WIDTH=640, GRASS_HEIGHT=480
WARNING: Unable to find
         '/home/neteler/grassdata/patUTM/neteler/cell_misc/pat_dtm_5m/f_format'
WARNING: Unable to open raster map <pat_dtm_5m at neteler>
ERROR: Unable to open raster map <pat_dtm_5m>

The same happens obviously in my local 6.4.svn backport.

Markus