The current solution uses one, bad valued Bezier curve and does not
toggle direction. The patch uses the more accurate solution from
basegfx and simplifies the decision tree. In addition it extracts the
calculation in double from GetPoint, so they can be used directly
instead of double->long->double conversion.

Change-Id: I298f49415d1b7624b36ca561647f2e58af5eb5c6
Reviewed-on: https://gerrit.libreoffice.org/65203
Tested-by: Jenkins
Reviewed-by: Regina Henschel <rb.henschel@t-online.de>