Manually. I chose line segments but it could have been circles, squares, boxes or donkeys.
I just dropped my shape onto the line and turned it to fit, which is why it is a bit rough.
I wasn't trying to replicate your line, just demonstrate a method that used Xara vectors instead of SWF or animated GIFs.
If it was just for this line I would have used HTML 5's Canvas.
The Xara approach doesn't require any other editor.
Acorn
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