[Gimp-developer] Border artifact from using nohalo to scale a layer with an alpha channel

[Elle Stone <ellestone ninedegreesbelow com>]

The following three bugs are closed, but there still seems to be a 
related? new? bug with nohalo scaling (and probably lohalo, but not with 
cubic or linear):

https://bugzilla.gnome.org/show_bug.cgi?id=634901
Bug 634901 - Resizing an image with alphachannel creates 1 pixel border 
down and right

https://bugzilla.gnome.org/show_bug.cgi?id=698601
Bug 698601 - scaling up without alpha adds several-pixel gradient border

https://bugzilla.gnome.org/show_bug.cgi?id=734378
Bug 734378 - Image manipulation (scale,rotate) may cause vertical image 
artefacts

Scaling up or down using nohalo produces a partially transparent border 
around the layer if the layer has an alpha channel. This is a 
long-standing issue that still obtains (at least scaling down has 
produced the edge artifact for a long time, bug 698601 describes the 
opposite situtation for scaling up).

I only just discovered that removing the alpha channel at least 
sometimes allows to scale a layer without creating the edge artifacts. 
So I'm not sure if removing the alpha channel always allows to scale 
without creating edge artifacts.

This bug was confirmed using babl/GEGL/GIMP updated today.

Should I file a new bug report? or maybe instead open one of the old bug 
reports?

Elle