[GRASS-user] Virtual Mosaic import with r.external

[Markus Neteler]

On Thu, Dec 25, 2014 at 2:20 AM, Jeshua Lacock <jeshua at 3dtopo.com> wrote:
>
>> On Dec 24, 2014, at 5:10 PM, Jeshua Lacock <jeshua at 3DTOPO.com> wrote:
>>
>> I was following along the Large raster data processing wiki with great interest:
>>
>> My question is, when tiles are merged in GRASS using a virtual mosaic created with gdalbuildvrt, will transparent map collars be preserved?  I see the man page for r.external talks about the requirement to build a mask or use r.mapcalc, but I don’t understand how I would apply that to a virtual mosaic. Is
>
> It appears that GDAL_TIFF_INTERNAL_MASK may be just what I need to use. I wonder if that option is respected using r.external? Thanks!

I suppose that would apply to r.external.out as it seems to be related
to the creation of GeoTIFF (see http://www.gdal.org/frmt_gtiff.html).

Markus