In this file, I have a given spline, which is fixed and the tangent at the origin.
(Btw, I am wondering why I can fix the tangent at origin : if the spline is fixed, the tangent at any point too, but it's not the matter of my post)
I want to define a segment, being tangent at the origin.
So, I draw a segment, one point at origin, the other free, and I define a tangent property.
And I get what is on my screen.
How can I build this totally elementary construction ?
OK, I can declare some colinearity with the tangent of the spline.
But this kind of behaviour is surely totally normal ?