Hi,
I see some action on rewriting Inkscape's General Ellipse code. It would be very nice if Inkscape could directly create the SVG circle and ellipse elements rather than use the SVG path element. I realize that this may be outside the scope of the current work but there is one thing that I should bring attention to: The SVG Working Group decided to allow markers on SVG shape elements.[1] Inkscape will actually already draw markers on shapes if there already are markers placed on the shapes in the SVG file (but doesn't draw them "correctly"), however Inkscape does not allow one to add markers to shapes through the GUI. (I'm sure that the drawing of the markers is accidental and not intentional.)
It was fairly clear to the SVG WG that for rectangles, there are four markers (one for each corner) and for rounded rectangles, there are eight markers (one at each start and end of a corner arc). See attachment.[2] It wasn't as clear what to do for circles and ellipses. The group decided that there should be four markers on circles and ellipses, located at the 0, 90, 180, and 270 degree points. Inkscape currently represents circles and arcs as two path elliptical arc segments. In order to have four markers, it should be using four elliptical arc segments.
I also noticed that the Object->Path command converts a circle/ellipse to a path using eight Bezier curves (and would thus have eight markers). It seems to me that it should be converting to four elliptical arc segments. (After all, converting a rectangle to a path doesn't produce four straight Bezier curves!)
Tav
[1] http://www.w3.org/2013/06/03-svg-minutes.html#item03 [2] Top row: expected behavior, bottom row: test. Green: Start marker, Yellow: Mid marker, Red: End marker.