Circle Tangent on a sphere ?

 From:  Frenchy Pilou (PILOU)
5435.1 
Does it possible to draw a given circle tangent "anywhere" on a sphere under the mouse ?

I can use Orient then Project Curve but maybe a trick exists for make that directly ?

ISO curve is only 2 directions and you don't know the measure of the circle on drawing

Circle 3 points but you dont know where point for have a circle given without construction

EDITED: 29 Sep 2012 by PILOU