When the arc location lies outside the sweep from the first leg to the second,
the arc runs from leg 2 to leg 1. The extension lines, DIMSE1/DIMSE2 and
DIMBLK1/DIMBLK2 still took the arc start as leg 1, so each extension line was
sized from the other leg. A short leg got no extension line, a leg already
crossing the arc got one drawn along it, and DIMSE1/DIMSE2 suppressed the
wrong line. The arc's ends are now paired with their legs.
Radius and diameter dimensions drew the DIMCEN mark even when the dimension
line is inside the circle. As in AutoCAD, the mark is now drawn only when the
line is outside: a radius led out to its text. A diameter line runs through
the centre, so it gets no mark.
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
