Illusionism in art, is a kind of visual trickery in which painted forms seem to be real. It is sometimes called trompe l'oeil. The development of one-point perspective in the Renaissance advanced illusionist technique immeasurably. It was highly developed in the Baroque period.
- The illusionism of the mirror image works because it reflects an image that convinces the viewer of its reality. Girl reading a Letter at an Open Window by Johannes Vermeer (1632-1675) makes use of this space construction, through the reflection of a face in the window.
- Las Meninas by Diego Rodríguez de Silva y Velázquez (1599-1660). The art historian Leo Steinberg described how:
- "the literature on Las Meninas is an epitome of recent thinking about illusionism and the status of art...a cherished crux for modern investigators, for geometricians, metaphysicians, artist-photographers, semioticians, political and social historians and even rare lovers of art."