I can draw tan from a curve a circle or curve, there are tools for that, however how does one move a curve so it snaps tan to a curve ?
In this example I wish to move the elipse upwards and have it snap tan to line D.
I then wish it to remain tan as I scale it north south scale1D to snap it to line F., keeping it tan at line at right.
What is the basic principle of snap tan then also scaling keeping tan ?
If you move the ellipse so that it intersects D tangentially and then scale the ellipse the point at which it would be tangential to D moves around the curve (the shallower the ellipse, the closer to the rhs) so this isn’t going to work.
Instead, just Scale1D the ellipse using the intersection with F as the base point and the quad at the top of the ellipse as the first point, then zoom in and adjust the mouse position so that you get the tangential intersection with D by eye.
That’s the quick way, but here are methods for moving and scaling the ellipse by drawing if you don’t like the idea of eyeing it in.
To move the ellipse to a tangential intersection with line D, make a copy of line D, copying from a point on D somewhere near the tangent point to the actual tangent snap on the ellipse.
Then move the ellipse upward by the distance between the two lines (e.g. using the points where they intersect the vertical line).
To scale the original ellipse to get a tangential intersection with D, while retaining the intersection with F, start with the same copy of D to a tangential intersection with the ellipse and mark the intersection.
Now Scale1D the ellipse down slightly and copy the first tangential D line from the marked point to the tangential snap on the new ellipse and mark the new intersection:
Then Scale1D the ellipse using the point where the perpendicular crosses F as the base, where it crosses the upper curve of the ellipse as the first point and the tangent point on D as the second point:
