Illusionistic ceiling painting, which includes the techniques of perspective di sotto in sù and quadratura, is the tradition in Renaissance, Baroque and Rococo art in which trompe l'oeil, perspective tools such as foreshortening, and other spatial effects are used to create the illusion of three-dimensional space on an otherwise two-dimensional or mostly flat ceiling surface above the viewer. It is frequently used to visually suggest an open sky, such as with the oculus in Andrea Mantegna's Camera degli Sposi, or a fictive architectural space such as in the illusionistic cupola, one of Andrea Pozzo's frescoes in Sant'Ignazio, Rome.
Di sotto in sù (or sotto in su), which means "seen from below" or "from below, upward" in Italian, developed in late Quattrocento Italian Renaissance painting, notably in Andrea Mantegna's Camera degli Sposi in Mantua and in frescoes by Melozzo da Forlì. Italian terminology for this technique reflects the latter artist's influence and is called prospettiva melozziana, or "Melozzo's perspective". Another notable use is by Antonio da Correggio in the Duomo of Parma, which foreshadows Baroque grandeur.
The technique often uses foreshortened figures and an architectural vanishing point to create the perception of true space on a painted, most-often frescoed, ceiling above the viewer.