[GRASS-user] no nulls outside project map area

William Kyngesburye woklist at kyngchaos.com
Fri Jun 5 16:43:35 EDT 2009

I started with a tiff image, in Albers projection.  Imported in a new  
location in GRASS - the tiff region is rectangular with no nulls in  
the region, so the GRASS region follows the tiff region exactly.

Then I projected to a latlong location.  The tiff is off to one side  
of the central meridian, so the projected image appears rotated and  
stretched, as expected:

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But the the triangular areas outside the original tiff region are  
white, not null.  My latlong region is larger than the image - I'm  
going to merge multiple tiled and overlapping tiffs - and there are  
nulls outside the extents of the projected area of the image.

Is this expected behavior?  I usually go from latlong to projected  
location, and the source latlong region is larger than the projected  
region so I don't see this.

GRASS 6.5svn

William Kyngesburye <kyngchaos*at*kyngchaos*dot*com>

Earth: "Mostly harmless"

- revised entry in the HitchHiker's Guide to the Galaxy

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