I am using the latest GIT of the STABLE branch (2.6.8) and am noticing  
an anomaly when scaling layers. When upscaling a fully opaque layer  
using the Scale Tool, the edges of the resulting layer are sometimes  
have partial transparency. This doesn't always happen -- it seems  
dependent upon the original and target sizes -- but it never seems to  
occur when using "Scale Layer..." from the menus. While I am not sure  
it should be considered a bug, my expectation would be that a fully  
opaque layer should remain fully opaque when upscaled.

To demonstrate this behavior, create a new white image with the  
dimensions 335x500, then create a new black layer with the dimensions  
120x135 positioned with the top-left corner at 0,0. Using the Scale  
Tool, type in the new dimensions of 335x500 and click "Scale". If you  
zoom in on the lower-right corner, the semi-transparency of the right  
and bottom edges should be evident.

Repeating the above, but using the menu command "Layer->Layer  
Scale...", you should see that all of the edges are completely opaque.

I would also note that the behavior described in Bug #603620  
(https://bugzilla.gnome.org/show_bug.cgi?id=603620) may have similar  
underpinnings, and that the author of that report suggested this was a  
regression from GIMP 2.4 behavior (I don't have access to 2.4 at the  

As a final comment, the PDB functions 'gimp-drawable-transform-scale'  
and 'gimp-drawable-transform-scale-default' both exhibit this  
anomalous behavior (for all interpolation modes except None). Indeed,  
it is when scripting that I find this behavior problematic.

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