Make corner rounding work for non-orthogonal joints
Make corner rounding work for non-orthogonal joints

The interior angle of the joint was not considered when determining
the trim length during rounding.  Acute angles would get too small a radius
and obtuse angles too large.

Single segment circular arcs are not well approximated by cubic Bezier
curves when the arc angle is greater than 90 deg.  This would happen when
rounding a corner of a sharply acute angle.

By splitting any corner round arc into two cubic Bezier curves, we can
guarantee that both have angles less than 90 deg.  This improves the
circularity of corner rounds for acute angles significantly.

ramcdona/Code-Eli