[Lib2geom-devel] tangent to curve

[Tavmjong B. <tav...@fr...>]

Hi,

It seems that the tangent at a beginning of a curve can flip sign with
slight changes to the curve (as returned by unitTangentAt()). Is this a
known problem? There is a comment that the tangent at the end of a line
can be wrong but nothing to indicate that the tangent at the beginning
can be wrong. This appears to be the cause of mis-drawn line joins.

Tav