Aware of those, but…
I wished to keep this simple as those threads became a mix of methods not all actually grasping what my problem and aim was. Whilst showing various methods which I now have stored should I need them, I was unable to apply them in this case ,maybe I missed something.
In this post I am starting away from the circle and ending at it.
The answers were about starting from the circle which was my task back then, now in some cases that’s the same, doesnt matter, for what I now have to do I need to end at circle, I cant start at it.
Jeff had said Any point would work, maybe so technically as all four are tangent, but any point chosen on my circle would give such twists and not allow my curve to sweep and kiss, a moon orbit rather than a moon crash ! Even the original task still required an in orbit type apprach of the curve.
e.g. menno said
Why not put the circle in later using Circle Tangent to 2 or 3 curves?
My circle is one that is not decided by three or even two curves, and has to be where it is and of the diameter it is, it dictates the curve, it does not get dictated by it.
There is only one spot on this circle that lets my curve line flow nicely (tangentially) into the circle.
I wish to find that spot where as I move my mouse about and the curve moves up and down , it ‘kisses’ the circle or curve. Thats the point I am after finding, at that point it will be tangential and give me the natural sweep it was wanting to do to the circle. see the two others where i picked a tangent point as per some other suggestions, curvature graph tells all even if the mk1 eyeball doesnt.
Unless I am god I cant pick that point with line tangent to circle tool.
Maybe this in the first thread linked to here, an entry by Jim, is the best shot at this,
In the enclosed file shows how you might get the curve you want. The two
red lines are drawn as helpers. The red lines are tangent to the circle
with the other end about midway from the two start and end points in
your original interpolated curve. The cyan curve is what you get using
see that thread for his file.
He starts at the circle and using line tangent from curve draws a line out to halfway to the first point I will be drawing through, a visual aim at that point, (as extending the line misses the point).
He would have had the end of that line at the circle moving about a little as he did this. If I was to have my curve going through that point on circle, would the resulting circle when trimmed and joined to my curve be ok given this ‘subtle variation’ by eye junction for use as a profile for surfacing with sweep ? being aware of what subtle inaccuracies can do to surfaces in sweeps, I am after technical correct here.
Was that method of Jim better than my current method of ending curve …
Here is storyboard of my ‘visual’ method, is it as good as or better than Jim for technical acceptance in Rhino , how good would my result be v Jim for being used in a sweep ?
What is best way of establishing the kiss point on the circle ? I then trim to that and draw my curve ENDING at that point, and do I need to use n for end tangent when doing so ? and my curve enters moon orbit tangential to the moon !