Hi,

I am annotating many images. Often I have to choose between white or black for arrows, but if the arrow crosses both of these colors, there is no "good" color for the arrow. Also it should look good in print.

Solution can be double stroked arrow. I believe something like this has been asked before
http://www.inkscapeforum.com/viewtopic.php" onclick="readonly();return false;"smilies" src="images/smilies/tool_pen.gif" alt=":tool_pen:" title="Pen" /> and then use extension to convert it to double arrow.
2) Allow handles that only apply to the two long lines, and which are always oriented to the arrows axis (comparable to Illustrator, where bounding box is rotated with object)

mogliii, I believe that the end arrow marker can be made to have separate fill and stroke colors, but do not believe that the stroke itself can only have one color. I'm not sure I completely follow your explanation above, but your svg explanation is very clear. Here's one alternative: 1) draw a single colored arrow stroke as usual with the desired end marker, 2) use Path > Stroke to Path to convert this stroke into a path shape, 3) Set this new path's stroke to black and fill to white... if desired, you can use Path > Stroke to Path again leave only paths behind. An arrow made this way should also scale and rotate without trouble.

You could certainly write an extension to create an arrow like this that is simply oriented facing up like in your svg example. It may also be possible to automate the steps above in an extension, but this would be more difficult because it would need to utilize inkscape's Path > Path to Stroke functionality (or implement it's own). I believe this may be possible by having your extension run an instance of inkscape from the command line, but am not sure since I haven't tried this before.

Hope this is helpful.