I want to thank everyone who responded.
The AutoRotate script does what I want, pretty much.
I am studying Scheme, which looks adequate to handle my desire for
drawing shapes to call out parts of screen captures.
Afterwards, I plan to start trying to comprehend the GIMP project, which
seems necessary for drawing arrows.
I'm finding the documentation difficult. I don't mean that I don't
understand the vast amount of work put into it nor the completeness of
I think my problem is more a matter of a beginner being overwhelmed by
the size and the number of choices.
What I've found very helpful in other projects of this type is a
community wiki, where a beginner like me can submit a "here's how I
took my first step" tutorial. The problem is the first steps are
incomprehensible until you take them, then they become trivial. People
who know the project can't really think up the questions, although they
are the ones with the answers. (Rereading that, I hope it makes sense
to someone besides me).
Just for the record, I've been using GIMP almost exclusively these days
and hopefully will be contributing to the project soon.
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