[gdal-dev] Using GRASSDataset

[Aleksey]

Frank,

thanks for the great work! Just tested it and it works, GDAL returns correct 
min/max for a GRASS dataset, and my little viewer is able to draw DEM instead 
of a black rectangle. Also, loading the same data from GRASS is faster than 
from an ASCII USGS file, so I am happy with the GRASS support.

Best regards,
Aleksey

On Thursday 24 January 2002 10:57, you wrote:
> Alexsey,
>
> I have corrected handling of null values for floating point layers (and to
> some extent for integer layers) in the grass driver within GDAL. Hopefully
> accessing your DEM will work better now.
>
> Note that all integer layers will report zero as their "nodata" value even
> if it is desirable that zero be a valid value. I don't quite get how this
> is supported to be address within GRASS and may need to review it in the
> future.
>
> For floating point layers I have selected -12345.0 as being the nodata
> value and the "null" mask from GRASS is read to establish it. All "nan"
> values are now converted to this value and the GetNoDataValue() method on
> bands returns the nodata value properly.
>
> Best regards,