It works in Visio 2013 for hatching.
But not works for gradation that is new function in Visio 2013.
It works when I save as vsd that is file type for Visio 2010 and save as svg,
but does not work when saved as vsdx that is new file type for Visio 2013 and save as svg.
I think Visio 2013 is not complete, either.