Informative message displayed if fewer than 3 matched control points are selected #2
Description
It would be nice if an informative message was displayed if fewer than 3 matched control points are selected.
This hasn't come up for us in a real-world situation yet, but when I was showing someone how to use the picking functions we closed the window after doing just one or two. Since we need at least 3 control points to compute the affine transformation, that part won't work if there aren't enough points. It would be relatively easy to check the number of points straight away, and then show a useful message if there are less than three matched control points.