Cut radius of circle of nub movement into a 1:1 square that fits the 16:9 sides for perfect alignment?Mouse controls cursor position, nubs control cursor velocity.
As you move a mouse, every quantum of movement gets its own event. As long as the mouse moves the cursor should as well. When you stop the mouse, the cursor should too.
As you move an analog nub, every quantum of change in its position gets its own event. As long as the nub position changes, the velocity of the cursor should as well. When you stop moving the nub, the cursor should keep moving to the direction the nub is being held at. There's no further events to move the cursor with until the nub is moved again.
At-least for desktop use that is interesting.