In computer graphics, a drop shadow is a visual effect consisting of drawing that looks like the shadow of an object, giving the impression that the object is raised above the objects behind it. The drop shadow is often used for elements of a graphical user interface such as windows or menus, and for simple text. The text label for icons on desktops in many desktop environments has a drop shadow, as this effect effectively distinguishes the text from any colored background it may be in front of.
A simple way of drawing a drop shadow of a rectangular object is to draw a gray or black area underneath and offset from the object. In general, a drop shadow is a copy in black or gray of the object, drawn in a slightly different position. Realism may be increased by:
- Darkening the colors of the pixels where the shadow casts instead of making them gray. This can be done with alpha blending the shadow with the area it is cast on.
- Softening the edges of the shadow. This can be done by adding Gaussian blur to the shadow's alpha channel before blending.
Famous quotes containing the words drop and/or shadow:
“Misfortunes leave wounds which bleed drop by drop even in sleep; thus little by little they train man by force and dispose him to wisdom in spite of himself. Man must learn to think of himself as a limited and dependent being; and only suffering teaches him this.”
—Simone Weil (1909–1943)
“A perfect beauty of a sunflower! a perfect excellent lovely sunflower existence! a sweet natural eye to the new hip moon, woke up alive and excited grasping in the sunset shadow sunrise golden monthly breeze”
—Allen Ginsberg (b. 1926)