image by Alberto Fernandez Fernandez via Wikimedia Commons, reproduced under GNU FDL

Trompe-l’œil(also spelled trompe l-oeuil) which is French for ‘deceive the eye’, is an artistic style that uses realistic imagery to create the optical illusion that the depicted objects are three dimensional. Trompe-l’œil has been used in art since the ancient Greeks and Romans, and it was particularly popular during the Italian Renaissance, where it was often used in church interiors. This is a truly amazing fresco that convinces you that the church has a dome in the ceiling. It does not. It’s all an illusion.
From Wikipedia:

Andrea Pozzo (Latinized version: Andreas Puteus; 30 November 1642, Trento, Italy – 31 August 1709, Vienna, Austria) was an Italian Jesuit Brother, Baroque painter and architect, decorator, stage designer, and art theoretician. He was best known for his grandiose frescoes using illusionistic technique called quadratura, in which architecture and fancy are intermixed. His masterpiece is the nave ceiling of the Church of Sant’Ignazio in Rome. Through his techniques, he has become one of the most remarkable figures of the Baroque period.

Andrea Pozzo was born in Trento, (now Italy, but then under Austrian rule). He showed early artistic talent and was apprenticed to work with several artists where he learned the techniques of Baroque art.
In 1665, he entered the Jesuit Order as a lay brother. At that particular time the Jesuits were a relatively new order in the Catholic Church, therefore many of their churches were newly built and lacked painted decorations. Discovering his talents, the Jesuits soon put him to work decorating churches and buildings all over Italy. His masterpiece, Sant’Ignazio in Rome, came about because that church remained unfinished after the Jesuits fell into a dispute with the original donors, the Ludovisi, and ran out of money to construct the dome that had been planned.

Pozzo proposed painting an illusion of a dome on the flat ceiling. In this photo you can see the results; the illusory “dome” and the nave ceiling of the Church of Sant’Ignazio, which appears to be open to the sky. As you can see, the whole thing is quite over the top! It’s the pinnacle of Baroque style. I guess either you love it or you hate it. I wouldn’t want to live with it, but I find it fascinating to study. It was the signature style of the Catholic Church at that time, developed in reaction to the more austere style of the Protestant Reformation, although Baroque later made inroads into the Protestant northern countries of Europe.

In 1703, Pozzo was invited by the emperor Leopold I to redecorate the Jesuitenkirche(Jesuit Church) in Vienna, also known as the University Church because it is adjacent to the University of Vienna. He redesigned the exterior as well, adding the twin towers seen in the photo and reworking the facade in an early Baroque style with narrow horizontal and vertical sections. The design of the windows, narrow niches (with statues) and the small central part of the façade deviate from the Baroque style of the towers.

But the real masterpiece is the semicircular vault ceiling which is divided in four bays and decorated with paintings in perspective using trompe l’oeil techniques, which Pozzo created in 1703. Click here and then click again on the photo to see an enlarged view. Keep in mind that the dome is painted on a flat surface. Churches with trompe l’oeuil ceilings often have a brass disk embedded in the floor, which marks the spot for a visitor to stand to get the best three-dimensional effect.

Trompe l’oeil is still very popular, especially for street murals, which I plan to talk about here in the future. It’s also commonly used in set designs, for films and theatre. But I don’t believe anyone has yet surpassed Pozzo and the other artists of the Renaissance in their mastery of this style.