Hi Ivan and Alan!

I'm not sure that is the correct place for the patch.

Could you enable NSTRACE (by uncommenting the line defining NSTRACE_ENABLED
in nsterm.h) and see which function calls `drawRect` (if possible). If that
is in a function that is part of Emacs, it's better to check that the frame
is visible higher up in the call chain.

You will have to start Emacs from a terminal window in order to see the
trace output. You can do this by running
"./nextstep/Emacs.app/Content/MacOS/Emacs".

    -- Anders