Illustration of the DRAGyS method, illustrating the ellipse estimation of the disk (red), and the geometrical method of recovering the different structure parameters. Left: image seen by the observer, with the ellipse in red and different estimated quantities, such as the semiminor and semimajor axes, m and M, the position angle, PA, and the projected distance between the star and the major axis, D, used to compute the aspect ratio. Right: sketch of protoplanetary disk observation. The point of view of observer 1 highlights the geometrical process to recover the disk geometry, namely the scattering surface height, h, at a radius, r_mid, and the inclination, i. The point of view of observer 2 illustrates the definition of the scattering angle.