Since I installed a new version, the semi-transparency is cut off
and I have just plain black on transparent background as if there
were no antialiasing, very ugly.
I wrote a script a while back that attempted to address this
works by replacing the non-transparent portion of each layer with the
result of merging the layer with the layers below (actually the
"projection" of the layers below it).
The image at
http://flashingtwelve.brickfilms.com/GIMP/Temp/de-alias.png might help
explain the result. An opaque background is expected and that gets
"hard-coded" into all non-transparent portions of the GIF. Fully
transparent regions remain transparent (but I doubt if this fact would
be of much use other than keeping filesize down).
I got it working only to the extent that I needed it, so there may be
some bugs in it of which I am unaware. If you let me know whether the
script needs modification, I might revisit it.
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