A three-dimensional (3D) photo cube is a computer application or script that displays a six-sided cube on the screen and each of the faces of the cube contains an image or photograph, usually one defined by the user. The relatively simple elements of a 3D photo cube allow the effect to be used in nearly any context, including in computer screen savers, multimedia applications, websites and embedded devices, and as a special-effects filter in some graphical image editors. In most implementations, the cube is not static but constantly rotates on an axis and sometimes even moves slowly across the screen. More complex versions of a 3D photo cube can have additional effects applied to the cube, including reflections, animations and interactive elements that allow a user to move or control the cube.
Many people use a 3D photo cube because it is a simple, interesting and compact method that displays a number of photographs simultaneously. Each of the faces of the cube can contain a different photograph, and the cube rotates slowly, so each of the six photographs will be shown over time while hinting at the other photographs, which might not be in full view. Some programs even allow the cycling of different photographs over time so the images on the sides of the cube automatically change at given intervals.
One complication that a 3D photo cube might have is the fact that each face on the cube is a square, while the shape of most photographs is rectangular. The default behavior of some 3D photo cube applications in this regard varies but can include automatically cropping an image to a smaller size, centering the larger image so the center shows in the square, or scaling the image so there is a gutter on the top and bottom within the cube face. A better result would require the user to edit the digital photographs to be used, making them square before loading them into the 3D application.
A more advanced version of a 3D photo cube program could include interactivity as one of its features. This can be especially entertaining when the program is run on a handheld device in which the angle and pitch of the device can be tied to the movements of the cube. Some cubes are programmed to follow the mouse cursor or to change facing based on keyboard input. One common feature is the ability to switch from the 3D photo cube to a full-screen viewing mode for the photograph that is facing the screen.