[Bug 57435] New: D2D1GeometrySinc::AddArc() doesn't properly mark end of the figure segment

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=57435

Bug ID: 57435
           Summary: D2D1GeometrySinc::AddArc() doesn't properly mark end
                    of the figure segment
           Product: Wine
           Version: 9.21
          Hardware: x86-64
                OS: Linux
            Status: NEW
          Keywords: source, testcase
          Severity: normal
          Priority: P2
         Component: d2d
          Assignee: [e-mail]
          Reporter: [e-mail]
      Distribution: ---

Created attachment 77431
  --> https://bugs.winehq.org/attachment.cgi?id=77431
Rounded rect under Wine

If an application creates a rounded rect geometry manually using a sequence of
calls ::AddLine() and ::AddArc() instead of ::CreateRoundedRectangleGeometry()
then the created rectangle is distorted under Wine.

While D2D1GeometrySinc::AddArc() is currently a stub, it tries to be smart and
calls d2d_figure_add_vertex() to add a terminating arc point to the figure,
however this doesn't work, and next call to ::AddLine() draws the line from the
point where previous line was terminated instead of an added vertex, and this
leads to drawing a distorted rectangle.

A simple implementation of ::AddArc() that calculates points of two arc
quadrants and calls d2d_geometry_outline_add_arc_quadrant() helper also suffers
from the same problem: added arc quadrants don't seem to properly mark end of
the figure segment. This seems to be caused by difference between how
::AddLines() and d2d_geometry_outline_add_line_segment() (used by
d2d_rounded_rectangle_geometry_init() helper called from
::CreateRoundedRectangleGeometry()) create line segments.

Attached test applications (source + binary) use both described above
approaches:
::CreateRoundedRectangleGeometry() and ::AddLine() + ::AddArc().

See screenshots for the Windows vs. Wine comparison.