Ellipses
Ellipse by Bounding Box
Set the start point, move and define the end point of the diagonal. The ellipse is inscribed in the rectangle defined by its diagonal.
Ellipse by Center and Radii
Click to set the center of the ellipse, move and click to define its first radius; move again and click to set its second radius. The center can also be defined by using the X, Y coordinates and the radii can be defined by pressing the L key during their construction.
Quarter of Ellipse
This method allows you to draw quarters of ellipse by clicking on its two vertices.