Trompe L'oeil is French for "trick of the eye", and refers to any style of media (usually painting) intended to create an optical illusion to fool the viewer. The earliest remaining example of trompe l'oeil was found in the unearthing of Pompeii, and is thousands of years old.
The most common illusion created with trompe l'oeil is one of false depth, usually accomplished by utilizing a number of simple techniques, including:
- Painting still-life subject matter, so that the lack of movement does not betray the illusion.
- Placing the painting in its natural location — windows at the right height on walls, doors in reasonable places, crawling plants on the outside of stone structures — to help the eye pass over them.
- Utilizing shallow shadow depth to make the items look like they are actually present in a number of lighting conditions.
- Ensuring no major objects in the piece are terminated at the end of the painting, reducing subliminal cues that make the brain look for a picture.
The illusion of depth was used extensively during the baroque period to "open" the enclosed spaces of cathedrals and churches. Painters of the day would design massive murals depicting open archways (complete with painted-on columns) looking out on sunlit, rolling hills and meadows. The trompe l'oeil style allowed architects to design enclosed spaces which could be reasonably heated and protected from the elements, while allowing for the feeling that one was in direct contact with the natural world.
Stories of animals mistaking trompe l'oeil paintings for reality are many, ranging from Roman writers reporting real horses whinnying greetings to painted horses, to birds trying — and failing — to land on murals of gates or birdbaths. These stories are undoubtedly exaggerated, given most animals' heavy reliance on senses other than sight to identify objects in their immediate surroundings.
Humans, however, are easily fooled, and many credible tales of people mistaking trompe l'oeil for the real thing exist. The historian Vasari relates the tale of an art contest in Italy, in which two artists competed for the title of greatest painter. One revealed a painting of fruit so realistic that nearby birds flew down and pecked at the painting, trying to eat the food. The judge then turned to the second painter and instructed him to reveal his painting by pulling aside the curtains masking it. The second painter smiled in triumph, as the curtains themselves were his painting — so realistic they had fooled everyone present.
While depth remains the most popular and well-known form of trompe l'oeil, others do exist. Da Vinci invented a special form of trompe l'oeil known as anamorphosis ("to change shape" in Greek), in which a picture is painted using exaggerated perspective, so that when viewed from many points it is hardly recognizable as the subject. When viewed from the correct perspective, however, it appears to have perfect proportions. The most well-known example of this style can be found on the ceiling of the Church of the Gesu in Rome. A large X marks the spot on the floor where the ceiling is meant to be viewed from. This style allows the painter to adjust for situations where the most common viewing angle will not be head-on, retaining their desired proportions no matter how extreme the angle might be. Road markings (indicating such things as "Stop Ahead") could be viewed as a rather mundane example of anamorphosis.
Trompe l'oeil has seen a resurgence of popularity in the last century, with a number of architects employing it to help open spaces, or simply to dress up designs. Contests abound throughout the United States and internationally, rewarding the best artistic use of trompe l'oeil. Perhaps most widely used are more pragmatic trompe l'oeil, such as those meant to provide the illusion of a faux finish, craquelure, or wooden paneling on objects that are otherwise unadorned.