[GRASS-user] no nulls outside project map area

William Kyngesburye woklist at kyngchaos.com
Fri Jun 5 16:52:32 EDT 2009

Ugh - tried it with GRASS 6.4 and I get the nulls.  Looks like a GRASS  
6.5 bug.

On Jun 5, 2009, at 3:43 PM, William Kyngesburye wrote:

> 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:
> <unprojected.png>
> 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>

"Oh, look, I seem to have fallen down a deep, dark hole.  Now what  
does that remind me of?  Ah, yes - life."

- Marvin

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