https://bugs.winehq.org/show_bug.cgi?id=48877
--- Comment #6 from Jeff Smith whydoubt@gmail.com --- About 60 lines from the end, I found something that matches what I suspected.
00a1:trace:gdiplus:GdipStartPathFigure (0000000006EF5CD0) 00a1:trace:gdiplus:GdipAddPathLine2 (0000000006EF5CD0, 0000000000228A10, 1) 00a1:trace:gdiplus:GdipGetPathLastPoint (0000000006EF5CD0, 0000000000228A10) 00a1:trace:gdiplus:GdipAddPathBeziers (0000000006EF5CD0, 0000000000228A10, 4)
We can fairly assume that the first bezier point is identical to the point added in GdipAddPathLine2. GdipAddPathBeziers is _supposed_ to recognize this and not duplicate the point.
I have a patch series that fixes this, and the equivalent bug in several other GdipAddPath* functions, that I will post to wine-devel shortly.