
Quadratura, a term which was introduced in the seventeenth century and is also normally used in English, became popular with Baroque artists. Although it can also refer to the "opening up" of walls through architectural illusion, the term is most-commonly associated with Italian ceiling painting. Unlike other trompe-l'oeil techniques or precedent di sotto in sù ceiling decorations, which often rely on intuitive artistic approaches to deception, quadratura is directly tied to seventeenth-century theories of perspective and the representation of architectural space. Due to its reliance on perspective theory, it more fully unites architecture, painting and sculpture and gives a more overwhelming impression of illusionism than earlier examples.
The artist would paint a feigned architecture in perspective on a flat or barrel-vaulted ceiling in such a way that it seems to continue the existing architecture. The perspective of this illusion is centered towards one focal point. The steep foreshortening of the figures, the painted walls and pillars, creates an illusion of deep recession, heavenly sphere or even an open sky. Paintings on ceilings could, for example, simulate statues in niches or openings revealing the sky.
The artist would paint a feigned architecture in perspective on a flat or barrel-vaulted ceiling in such a way that it seems to continue the existing architecture. The perspective of this illusion is centered towards one focal point. The steep foreshortening of the figures, the painted walls and pillars, creates an illusion of deep recession, heavenly sphere or even an open sky. Paintings on ceilings could, for example, simulate statues in niches or openings revealing the sky.