Translate SVG path arcs to OpenXML coordinates

Javascript function that function arcSVGtoOpenXML ( rx, ry, xAxisRot, largeArcFlag, sweepFlag, x, y) { ... magic return {h,w, stAng, swAng} } Acceptance criteria will be successfully translating the two arcs in this example: <path d="M 162.70987041992964 178.91665418743597 l -106.08334581256402 0 a 106.08334581256402 106.08334581256402 0 1 0 212.16669162512804 0 a 125 50 30 0 1 -212.16669162512804 0 "/>` See [login to view URL] 162.70987041992964 178.91665418743597 l -106.08334581256402 0 a 106.08334581256402 106.08334581256402 0 1 0 212.16669162512804 0 m 1 0 a 125 50 30 0 1 -212.16669162512804 0 ADDITIONAL INFORMATION I would like a function in Javascript that does the opposite of what this article does. SVG tags specify arcs as M <x> <y> A <rx> <ry> <x-axis-rot> <large-arc-flag> <sweep-flag> <x1> <y1> OpenXML <a:arcTo> specifies arc with a different parameters: <a arcTo w=<width> h=<height> stAng=<startAngle> swAng=<sweepAngle> > This article has C# code that goes from OpenXML parameters to SVG, [login to view URL] I would like a Javascript function that does the reverse. It's basically analytic trigonometry, but its a bit involved. I don't need to own the code, just an open source license to it. So you're free to post the solution in a blog, whatever too.