I made minimal changes to my copy of basemap to support the new quiver
and quiverkey, and to illustrate them in quiver_demo.py. The older
quiver is still accessible as quiver_classic. A diff against svn is
attached. (It includes do-nothing diffs caused by my editor's deletion
of end-of-line whitespace when a file is saved.) If you like, I can
commit the changes.
There is still what I hope is a minor flaw: when the aspect ratio is
controlled, as in basemap, it seems that the changes in rendered arrow
width upon zooming are a bit jumpy, and the key arrow width can end up a
bit different from the map arrow widths. I don't think this affects the
length, so the key is still valid (as far as I have been able to
determine.) I would like to improve this, but I don't think that use of
the new quiver needs to wait for it.