Scrolling
Encyclopedia
In computer graphics
, filmmaking
, television production, and other kinetic displays, scrolling is sliding text, images or video across a monitor or display. "Scrolling", as such, does not change the layout of the text or pictures, or but incrementally moves (pans
or tilts
) the user's view across what is apparently a larger image that is not wholly seen. A common special effect is to scroll credits, while leaving the background stationary. Smooth scrolling is a feature to reduce what the viewer would perceive as "jumps" (discontinuous movement) in the display. The computational effort of moving images and video smoothly is high, therefore successful smooth scrolling in text is most common. Frame rate
is speed at which an entire image is redisplayed. It is related to scrolling, in that changes to text and image position can only happen as often as the image can be redisplayed. When frame rate is a limiting factor, one smooth scrolling technique is to blur images during movement that would otherwise appear to "jump".
Scrolling can also refer to a certain misbehavior conducted in a chat room
whereby one person causes the screens of many others in a chat to scroll against their will by inserting much noise or special control characters.
-style graphical user interface
(GUI), scrolling is done with the help of a scrollbar
or using keyboard shortcuts, often the arrow keys. Scrolling is often a key feature in text user interface
s and command line interfaces, though some older computer terminal
s used a paging mode instead, akin to flipping through a series of pages in a book, usually using the Page Up and Page Down keys
or the space bar
. Computer mice may also have a scroll wheel
, which scrolls text vertically when rolled. (Some recent computer mice have scroll balls or tilt wheels which allow for horizontal scrolling.) Software such as Adobe Reader can also be scrolled with the hand tool
. In this case, the document is dragged and moved around like a piece of paper. When this feature is applied to touchscreen
s, it is referred to as kinetic scrolling.
Other PC mouse scrolling is available, although function varies widely between software applications. Some scroll wheels can be pressed down, functioning like a button. Depending on the software, this allows scrolling in both the horizontal and vertical directions by dragging in the direction desired; when the mouse is moved to the original position, scrolling stops. A few scroll wheels can also be tilted, scrolling horizontally in one direction until released.
If any content is too wide to fit on a display, horizontal scrolling is required to view all of it. In applications like graphics
and spreadsheet
s, the content often has a 2D structure, and horizontal scrolling can be useful and necessary.
), horizontal scrolling is much more inconvenient than vertical scrolling, because when reading the text in order, back-and-forth scrolling is needed for every line, as opposed to vertical scrolling, which is needed only after reading a whole window or column of text.
A web browser
normally places as many words in a single line as will fit the width of the browser window. Special HTML-code may instruct the browser to divide the window into columns, in which case it places as many words in a single line as will fit the width of the column.
written for home computer
s in the 1980s. They were particularly important in crack intro
s programmed by software cracker
s, where they were used to convey messages between groups involved in the activity.
Many scrollers were plain horizontal scrollers, but demo coders
also paid a lot of attention in finding new and different types of scrolling. The characters could, for example, continuously alter their shape, take unusual flying paths or incorporate color effects such as raster bar
s. Sometimes it makes the text nearly unreadable.
Scrolling is also used in television news in the lower third of the picture when a news ticker
is employed, scrolling news stories horizontally across the bottom of the screen.
's 1974 vertical-scrolling racing video game Speed Race, Sega
's 1976 forward-scrolling
racing games Moto-Cross
(Fonz) and Road Race, Sega's 1977 side-scrolling
shooter game
Bomber, and Super Bug.
Parallax scrolling, which was first featured in Moon Patrol
, involves several semi-transparent layers, which scroll on top of each other at varying rates in order to give an early pseudo-3D
illusion of depth. Belt scroll
is a method used in side-scrolling beat 'em up
games with downward camera angle where players can move up and down. A previously much used alternative to video game scrolling is the flip-screen
method.
Computer graphics
Computer graphics are graphics created using computers and, more generally, the representation and manipulation of image data by a computer with help from specialized software and hardware....
, filmmaking
Filmmaking
Filmmaking is the process of making a film, from an initial story, idea, or commission, through scriptwriting, casting, shooting, directing, editing, and screening the finished product before an audience that may result in a theatrical release or television program...
, television production, and other kinetic displays, scrolling is sliding text, images or video across a monitor or display. "Scrolling", as such, does not change the layout of the text or pictures, or but incrementally moves (pans
Panning (camera)
In photography, panning refers to the horizontal movement or rotation of a still or video camera, or the scanning of a subject horizontally on video or a display device...
or tilts
Tilt (camera)
Tilting is a cinematographic technique in which the camera is stationary and rotates in a vertical plane . A rotation in a horizontal plane is known as panning...
) the user's view across what is apparently a larger image that is not wholly seen. A common special effect is to scroll credits, while leaving the background stationary. Smooth scrolling is a feature to reduce what the viewer would perceive as "jumps" (discontinuous movement) in the display. The computational effort of moving images and video smoothly is high, therefore successful smooth scrolling in text is most common. Frame rate
Frame rate
Frame rate is the frequency at which an imaging device produces unique consecutive images called frames. The term applies equally well to computer graphics, video cameras, film cameras, and motion capture systems...
is speed at which an entire image is redisplayed. It is related to scrolling, in that changes to text and image position can only happen as often as the image can be redisplayed. When frame rate is a limiting factor, one smooth scrolling technique is to blur images during movement that would otherwise appear to "jump".
Scrolling can also refer to a certain misbehavior conducted in a chat room
Chat room
The term chat room, or chatroom, is primarily used by mass media to describe any form of synchronous conferencing, occasionally even asynchronous conferencing...
whereby one person causes the screens of many others in a chat to scroll against their will by inserting much noise or special control characters.
Computing
Scrolling is often done on a computer by the CPU or a graphics card. In a WIMPWIMP (computing)
In human–computer interaction, WIMP stands for "windows, icons, menus and pointers", denoting a style of interaction using these elements. It was coined by Merzouga Wilberts in 1980...
-style graphical user interface
Graphical user interface
In computing, a graphical user interface is a type of user interface that allows users to interact with electronic devices with images rather than text commands. GUIs can be used in computers, hand-held devices such as MP3 players, portable media players or gaming devices, household appliances and...
(GUI), scrolling is done with the help of a scrollbar
Scrollbar
A scrollbar is an object in a graphical user interface with which continuous text, pictures or anything else can be scrolled including time in video applications, i.e., viewed even if it does not fit into the space in a computer display, window, or viewport...
or using keyboard shortcuts, often the arrow keys. Scrolling is often a key feature in text user interface
Text user interface
TUI short for: Text User Interface or Textual User Interface , is a retronym that was coined sometime after the invention of graphical user interfaces, to distinguish them from text-based user interfaces...
s and command line interfaces, though some older computer terminal
Computer terminal
A computer terminal is an electronic or electromechanical hardware device that is used for entering data into, and displaying data from, a computer or a computing system...
s used a paging mode instead, akin to flipping through a series of pages in a book, usually using the Page Up and Page Down keys
Page Up and Page Down keys
The Page Up and Page Down keys are two keys commonly found on computer keyboards.The two keys are primarily used to scroll up or down in documents, but the scrolling distance varies between different applications...
or the space bar
Space bar
thumb|250px|A [[computer keyboard]], Space Bar is on the bottom center of the keyboardThe space bar, spacebar, or space key, is a key on an alphanumeric keyboard in the form of a horizontal bar in the lowermost row, significantly wider than other keys. Its main purpose is to conveniently enter the...
. Computer mice may also have a scroll wheel
Scroll wheel
A scroll wheel is a hard plastic or rubbery disc on a computer mouse that is perpendicular to the mouse surface. It is normally located between the left and right mouse buttons.- Functionality :...
, which scrolls text vertically when rolled. (Some recent computer mice have scroll balls or tilt wheels which allow for horizontal scrolling.) Software such as Adobe Reader can also be scrolled with the hand tool
Hand tool
A hand tool is a device for performing work on a material or a physical system using only hands. The hand tools can be manually used employing force, or electrically powered, using electrical current...
. In this case, the document is dragged and moved around like a piece of paper. When this feature is applied to touchscreen
Touchscreen
A touchscreen is an electronic visual display that can detect the presence and location of a touch within the display area. The term generally refers to touching the display of the device with a finger or hand. Touchscreens can also sense other passive objects, such as a stylus...
s, it is referred to as kinetic scrolling.
Other PC mouse scrolling is available, although function varies widely between software applications. Some scroll wheels can be pressed down, functioning like a button. Depending on the software, this allows scrolling in both the horizontal and vertical directions by dragging in the direction desired; when the mouse is moved to the original position, scrolling stops. A few scroll wheels can also be tilted, scrolling horizontally in one direction until released.
If any content is too wide to fit on a display, horizontal scrolling is required to view all of it. In applications like graphics
Graphics
Graphics are visual presentations on some surface, such as a wall, canvas, computer screen, paper, or stone to brand, inform, illustrate, or entertain. Examples are photographs, drawings, Line Art, graphs, diagrams, typography, numbers, symbols, geometric designs, maps, engineering drawings,or...
and spreadsheet
Spreadsheet
A spreadsheet is a computer application that simulates a paper accounting worksheet. It displays multiple cells usually in a two-dimensional matrix or grid consisting of rows and columns. Each cell contains alphanumeric text, numeric values or formulas...
s, the content often has a 2D structure, and horizontal scrolling can be useful and necessary.
One-dimensional content
Plain text is essentially linear, it does not have a 2D structure. For text in most scripts (with line-by-line ordering of characters on horizontal lines, as opposed to vertical writingHorizontal and vertical writing in East Asian scripts
Many East Asian scripts can be written horizontally or vertically. The Chinese, Japanese and Korean scripts can be oriented in either direction, as they consist mainly of disconnected syllabic units, each occupying a square block of space...
), horizontal scrolling is much more inconvenient than vertical scrolling, because when reading the text in order, back-and-forth scrolling is needed for every line, as opposed to vertical scrolling, which is needed only after reading a whole window or column of text.
A web browser
Web browser
A web browser is a software application for retrieving, presenting, and traversing information resources on the World Wide Web. An information resource is identified by a Uniform Resource Identifier and may be a web page, image, video, or other piece of content...
normally places as many words in a single line as will fit the width of the browser window. Special HTML-code may instruct the browser to divide the window into columns, in which case it places as many words in a single line as will fit the width of the column.
Demos
Scrolling texts, also referred to as scrolltexts or scrollers, were an integral feature of the majority of the demosDemo (computer programming)
A demo is a non-interactive multimedia presentation made within the computer subculture known as the demoscene. Demogroups create demos to demonstrate their abilities in programming, music, drawing, and 3D modeling...
written for home computer
Home computer
Home computers were a class of microcomputers entering the market in 1977, and becoming increasingly common during the 1980s. They were marketed to consumers as affordable and accessible computers that, for the first time, were intended for the use of a single nontechnical user...
s in the 1980s. They were particularly important in crack intro
Crack intro
A crack intro, also known as a cracktro, loader, or just intro, is a small introduction sequence added to cracked software, designed to inform the user of which "cracking crew" or individual cracker was responsible for removing the software's copy protection and distributing the crack...
s programmed by software cracker
Software cracking
Software cracking is the modification of software to remove or disable features which are considered undesirable by the person cracking the software, usually related to protection methods: copy protection, trial/demo version, serial number, hardware key, date checks, CD check or software annoyances...
s, where they were used to convey messages between groups involved in the activity.
Many scrollers were plain horizontal scrollers, but demo coders
Demoscene
The demoscene is a computer art subculture that specializes in producing demos, which are non-interactive audio-visual presentations that run in real-time on a computer...
also paid a lot of attention in finding new and different types of scrolling. The characters could, for example, continuously alter their shape, take unusual flying paths or incorporate color effects such as raster bar
Raster bar
The raster bar is an effect used in demos that displays animated horizontal bars of colour that extend into the overscan area of the display...
s. Sometimes it makes the text nearly unreadable.
Television
Scrolling is commonly used to display the credits at the end of television shows.Scrolling is also used in television news in the lower third of the picture when a news ticker
News ticker
A news ticker resides in the lower third of the television screen space on television news networks dedicated to presenting headlines or minor pieces of news. It may also refer to a long, thin scoreboard-style display seen around the front of some offices or public buildings...
is employed, scrolling news stories horizontally across the bottom of the screen.
Video games
In computer and video games, scrolling of a playing field allows the player to control an object in a large contiguous area. Early examples of this method include TaitoTaito
Taito may mean:*Taito Corporation, a Japanese developer of video game software and arcade hardware*Taito, Tokyo, a special ward located in Tokyo, Japan*Taito, also known as matai, paramount chiefs according to Fa'a Samoa...
's 1974 vertical-scrolling racing video game Speed Race, Sega
Sega
, usually styled as SEGA, is a multinational video game software developer and an arcade software and hardware development company headquartered in Ōta, Tokyo, Japan, with various offices around the world...
's 1976 forward-scrolling
2.5D
2.5D , 3/4 perspective and pseudo-3D are terms used to describe either:* 2D graphical projections and techniques which cause a series of images or scenes to fake or appear to be three-dimensional when in fact they are not, or* gameplay in an otherwise three-dimensional video game that is...
racing games Moto-Cross
Fonz (arcade)
Fonz is a 1976 arcade racing video game developed by Sega and published by Sega-Gremlin. The game was based on the hit TV show Happy Days and the slogan was "TV's hottest name, Your hottest game." The game itself was simply a rebranded variant of Sega's earlier 1976 game Moto-Cross in a customized...
(Fonz) and Road Race, Sega's 1977 side-scrolling
Side-scrolling video game
A side-scrolling game or side-scroller is a video game in which the gameplay action is viewed from a side-view camera angle, and the onscreen characters generally move from the left side of the screen to the right. These games make use of scrolling computer display technology...
shooter game
Shooter game
Shooter games are a sub-genre of action game, which often test the player's speed and reaction time. It includes many subgenres that have the commonality of focusing "on the actions of the avatar using some sort of weapon. Usually this weapon is a gun, or some other long-range weapon". A common...
Bomber, and Super Bug.
Parallax scrolling, which was first featured in Moon Patrol
Moon Patrol
is a classic arcade game by Irem that was first released in 1982. It was licensed to Williams for distribution in North America.The player controls a moon buggy, viewing it from the side, that travels over the moon's surface. While driving it, obstacles such as craters and mines must be avoided....
, involves several semi-transparent layers, which scroll on top of each other at varying rates in order to give an early pseudo-3D
2.5D
2.5D , 3/4 perspective and pseudo-3D are terms used to describe either:* 2D graphical projections and techniques which cause a series of images or scenes to fake or appear to be three-dimensional when in fact they are not, or* gameplay in an otherwise three-dimensional video game that is...
illusion of depth. Belt scroll
Belt scroll
Belt scroll is a video game genre that is side-scrolling action with downward camera angle. The character is able to move not only sideways but also vertical to depth within limited area.This term is mainly used in Japan...
is a method used in side-scrolling beat 'em up
Beat 'em up
Beat 'em up is a video game genre featuring melee combat between the protagonist and a large number of underpowered antagonists. These games typically take place in urban settings and feature crime-fighting and revenge-based plots, though some games may employ historical or fantasy themes...
games with downward camera angle where players can move up and down. A previously much used alternative to video game scrolling is the flip-screen
Flip-screen
In video games, flip-screen is a principle whereby the playing environment is divided into single-screen portions...
method.