Scrolling

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Parallax scrolling Parallax scrolling example scene.gif
Parallax scrolling

In computer displays, filmmaking, television production, and other kinetic displays, scrolling is sliding text, images or video across a monitor or display, vertically or horizontally. "Scrolling," as such, does not change the layout of the text or pictures but moves (pans or tilts) the user's view across what is apparently a larger image that is not wholly seen. [1] A common television and movie special effect is to scroll credits, while leaving the background stationary. Scrolling may take place completely without user intervention (as in film credits) or, on an interactive device, be triggered by touchscreen or a keypress and continue without further intervention until a further user action, or be entirely controlled by input devices.

Contents

Scrolling may take place in discrete increments (perhaps one or a few lines of text at a time), or continuously (smooth scrolling). Frame rate is the 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".

Computing

Implementation

Scrolling is often carried out on a computer by the CPU (software scrolling) or by a graphics processor. Some systems feature hardware scrolling, where an image may be offset as it is displayed, without any frame buffer manipulation (see also hardware windowing). This was especially common in 8 and 16bit video game consoles.

UI paradigms

In a WIMP-style graphical user interface (GUI), user-controlled scrolling is carried out by manipulating a scrollbar with a mouse, or using keyboard shortcuts, often the arrow keys. Scrolling is often supported by text user interfaces and command line interfaces. Older computer terminals changed the entire contents of the display one screenful ("page") at a time; this paging mode requires fewer resources than scrolling. Scrolling displays often also support page mode. Typically certain keys or key combinations page up or down; on PC-compatible keyboards the page up and page down keys or the space bar are used; earlier computers often used control key combinations. [notes 1] Some computer mice have a scroll wheel, which scrolls the display, often vertically, when rolled; others have scroll balls or tilt wheels which allow both vertical and horizontal scrolling.

Some software supports other ways of scrolling. Adobe Reader has a mode identified by a small hand icon ("hand tool") on the document, which can then be dragged by clicking on it and moving the mouse as if sliding a large sheet of paper. When this feature is implemented on a touchscreen it is called kinetic scrolling. Touch-screens often use inertial scrolling, in which the scrolling motion of an object continues in a decaying fashion after release of the touch, simulating the appearance of an object with inertia. An early implementation of such behavior was in the "Star7" PDA of Sun Microsystems ca. 19911992. [2]

Scrolling can be controlled in other software-dependent ways by a PC mouse. Some scroll wheels can be pressed down, functioning like a button. Depending on the software, this allows both horizontal and vertical scrolling 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. On touchscreen devices, scrolling is a multi-touch gesture, done by swiping a finger on the screen vertically in the direction opposite to where the user wants to scroll to.

If any content is too wide to fit on a display, horizontal scrolling is required to view all of it. In applications such as graphics and spreadsheets there is often more content than can fit either the width or the height of the screen at a comfortable scale, and scrolling in both directions is necessary.

Infinite scrolling

In 2006, Aza Raskin developed the infinite scrolling technique, whereby pagination of web pages is eliminated, in favor of continuously loading content as the user scrolls down the page. [3] Raskin later expressed regret at the invention, describing it as "one of the first products designed to not simply help a user, but to deliberately keep them online for as long as possible". [4] Usability research suggests infinite scrolling can present an accessibility issue. [3] The lack of stopping cues has been described as a pathway to smartphone addiction and social media addiction. [5] [6]

Text

In languages written horizontally, such as most Western languages, text documents longer than will fit on the screen are often displayed wrapped and sized to fit the screen width, and scrolled vertically to bring desired content into view. It is possible to display lines too long to fit the display without wrapping, scrolling horizontally to view each entire line. However, this requires inconvenient constant line-by-line scrolling, while vertical scrolling is only needed after reading a full screenful.

Software such as word processors and web browsers normally uses word-wrapping to display as many words in a single line as will fit the width of the screen or window or, for text organised in columns, each column.

Demos

Scrolling texts, also referred to as scrolltexts or scrollers, played an important part in the birth of the computer demo culture. The software crackers often used their deep knowledge of computer platforms to transform the information that accompanied their releases into crack intros. The sole role of these intros was to scroll the text on the screen in an impressive way. [7]

Film and television

Scrolling is commonly used to display the credits at the end of films and television programs.

Scrolling is often used in the form of a news ticker towards the bottom of the picture for content such as television news, scrolling sideways across the screen, delivering short-form content.

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 Taito's 1974 vertical-scrolling racing video game Speed Race , [8] Sega's 1976 forward-scrolling racing games Moto-Cross [9] (Fonz) [10] and Road Race, [11] and Super Bug. Previously the flip-screen method was used to indicate moving backgrounds.

The Namco Galaxian arcade system board introduced with Galaxian in 1979 pioneered a sprite system that animated pre-loaded sprites over a scrolling background, which became the basis for Nintendo's Radar Scope and Donkey Kong arcade hardware and home consoles such as the Nintendo Entertainment System. [12]

Parallax scrolling, which was first featured in Moon Patrol , involves several semi-transparent layers (called playfields), which scroll on top of each other at varying rates in order to give an early pseudo-3D illusion of depth. [13]

Belt scrolling is a method used in side-scrolling beat 'em up games with a downward camera angle where players can move up and down in addition to left and right.

Studies

A 1993 article by George Fitzmaurice studied spatially aware palmtop computers. These devices had a 3D sensor, and moving the device caused the contents to move as if the contents were fixed in place. This interaction could be referred to as “moving to scroll.” Also, if the user moved the device away from their body, they would zoom in; conversely, the device would zoom out if the user pulled the device closer to them. Smartphone cameras and “optical flow” image analysis utilize this technique nowadays. [14]

A 1996 research paper by Jun Rekimoto analyzed tilting operations as scrolling techniques on small screen interfaces. Users could not only tilt to scroll, but also tilt to select menu items. These techniques proved especially useful for field workers, since they only needed to hold and control the device with one hand. [15]

A more recent study from 2013 by Selina Sharmin, Oleg Špakov, and Kari-Jouko Räihä explored the action of reading text on a screen while the text auto-scrolls based on the user's eye tracking patterns. The control group simply read text on a screen and manually scrolled. The study found that participants preferred to read primarily at the top of the screen, so the screen scrolled down whenever participants’ eyes began to look toward the bottom of the screen. This auto-scrolling caused no statistically significant difference in reading speed or performance. [16]

See also

Notes

  1. The widely used Wordstar word processor used the "diamond" of Ctrl-S/E/D/X to move the cursor left, up, right, and down, and Ctrl-R and Ctrl-C to page up and down.

Related Research Articles

The GUI, graphical user interface, is a form of user interface that allows users to interact with electronic devices through graphical icons and audio indicator such as primary notation, instead of text-based UIs, typed command labels or text navigation. GUIs were introduced in reaction to the perceived steep learning curve of CLIs, which require commands to be typed on a computer keyboard.

The keyboard for IBM PC-compatible computers is standardized. However, during the more than 30 years of PC architecture being frequently updated, many keyboard layout variations have been developed.

Pointing device gesture

In computing, a pointing device gesture or mouse gesture is a way of combining pointing device or finger movements and clicks that the software recognizes as a specific computer event and responds to accordingly. They can be useful for people who have difficulties typing on a keyboard. For example, in a web browser, a user can navigate to the previously viewed page by pressing the right pointing device button, moving the pointing device briefly to the left, then releasing the button.

<span class="mw-page-title-main">Pointing device</span> Human interface device for computers

A pointing device is a human interface device that allows a user to input spatial data to a computer. CAD systems and graphical user interfaces (GUI) allow the user to control and provide data to the computer using physical gestures by moving a hand-held mouse or similar device across the surface of the physical desktop and activating switches on the mouse. Movements of the pointing device are echoed on the screen by movements of the pointer and other visual changes. Common gestures are point and click and drag and drop.

Scroll Lock Computer key

Scroll Lock is a lock key on most IBM-compatible computer keyboards.

Graphics tablet Computer input device

A graphics tablet is a computer input device that enables a user to hand-draw images, animations and graphics, with a special pen-like stylus, similar to the way a person draws images with a pencil and paper. These tablets may also be used to capture data or handwritten signatures. It can also be used to trace an image from a piece of paper that is taped or otherwise secured to the tablet surface. Capturing data in this way, by tracing or entering the corners of linear polylines or shapes, is called digitizing.

Control key Key on computer keyboards

In computing, a Control keyCtrl is a modifier key which, when pressed in conjunction with another key, performs a special operation ; similar to the Shift key, the Control key rarely performs any function when pressed by itself. The Control key is located on or near the bottom left side of most keyboards, with many featuring an additional one at the bottom right.

In computing, an icon is a pictogram or ideogram displayed on a computer screen in order to help the user navigate a computer system. The icon itself is a quickly comprehensible symbol of a software tool, function, or a data file, accessible on the system and is more like a traffic sign than a detailed illustration of the actual entity it represents. It can serve as an electronic hyperlink or file shortcut to access the program or data. The user can activate an icon using a mouse, pointer, finger, or recently voice commands. Their placement on the screen, also in relation to other icons, may provide further information to the user about their usage. In activating an icon, the user can move directly into and out of the identified function without knowing anything further about the location or requirements of the file or code.

<span class="mw-page-title-main">Text-based user interface</span> Type of interface based on outputting to or controlling a text display

In computing, text-based user interfaces (TUI), is a retronym describing a type of user interface (UI) common as an early form of human–computer interaction, before the advent of graphical user interfaces (GUIs). Like GUIs, they may use the entire screen area and accept mouse and other inputs. They may also use color and often structure the display using special graphical characters such as ┌ and ╣, referred to in Unicode as the "box drawing" set. The modern context of use is usually a terminal emulator.

<span class="mw-page-title-main">Touchscreen</span> Input and output device

A touchscreen or touch screen is the assembly of both an input and output ('display') device. The touch panel is normally layered on the top of an electronic visual display of an information processing system. The display is often an LCD, AMOLED or OLED display while the system is usually a laptop, tablet, or smartphone. A user can give input or control the information processing system through simple or multi-touch gestures by touching the screen with a special stylus or one or more fingers. Some touchscreens use ordinary or specially coated gloves to work while others may only work using a special stylus or pen. The user can use the touchscreen to react to what is displayed and, if the software allows, to control how it is displayed; for example, zooming to increase the text size.

Graphical widget Element of interaction in a graphical user interface

A graphical widget in a graphical user interface is an element of interaction, such as a button or a scroll bar. Controls are software components that a computer user interacts with through direct manipulation to read or edit information about an application. User interface libraries such as Windows Presentation Foundation, Qt, GTK, and Cocoa, contain a collection of controls and the logic to render these.

<span class="mw-page-title-main">Scroll wheel</span> The component of a computer mouse used for scrolling

A scroll wheel is a wheel used for scrolling. The term usually refers to such wheels found on computer mice. It is often made of hard plastic with a rubbery surface, centred around an internal rotary encoder. It is usually located between the left and right mouse buttons and is positioned perpendicular to the mouse surface. Sometimes the wheel can be pressed left and right, which is just two additional macros buttons.

In computer user interfaces, a cursor is an indicator used to show the current position for user interaction on a computer monitor or other display device that will respond to input from a text input or pointing device. The mouse cursor is also called a pointer, owing to its resemblance in usage to a pointing stick.

<span class="mw-page-title-main">Multi-touch</span> Technology

In computing, multi-touch is technology that enables a surface to recognize the presence of more than one point of contact with the surface at the same time. The origins of multitouch began at CERN, MIT, University of Toronto, Carnegie Mellon University and Bell Labs in the 1970s. CERN started using multi-touch screens as early as 1976 for the controls of the Super Proton Synchrotron. Capacitive multi-touch displays were popularized by Apple's iPhone in 2007. Plural-point awareness may be used to implement additional functionality, such as pinch to zoom or to activate certain subroutines attached to predefined gestures.

A text entry interface or text entry device is an interface that is used to enter text information in an electronic device. A commonly used device is a mechanical computer keyboard. Most laptop computers have an integrated mechanical keyboard, and desktop computers are usually operated primarily using a keyboard and mouse. Devices such as smartphones and tablets mean that interfaces such as virtual keyboards and voice recognition are becoming more popular as text entry systems.

<span class="mw-page-title-main">Computer keyboard</span> Data input device

A computer keyboard is a peripheral input device modeled after the typewriter keyboard which uses an arrangement of buttons or keys to act as mechanical levers or electronic switches. Replacing early punched cards and paper tape technology, interaction via teleprinter-style keyboards have been the main input method for computers since the 1970s, supplemented by the computer mouse since the 1980s.

<span class="mw-page-title-main">Input device</span> Provides data and signals to a computer

In computing, an input device is a piece of equipment used to provide data and control signals to an information processing system, such as a computer or information appliance. Examples of input devices include keyboards, mouse, scanners, cameras, joysticks, and microphones.

<span class="mw-page-title-main">DiamondTouch</span> Multiple person interface device

The DiamondTouch table is a multi-touch, interactive PC interface product from Circle Twelve Inc. It is a human interface device that has the capability of allowing multiple people to interact simultaneously while identifying which person is touching where. The technology was originally developed at Mitsubishi Electric Research Laboratories (MERL) in 2001 and later licensed to Circle Twelve Inc in 2008. The DiamondTouch table is used to facilitate face-to-face collaboration, brainstorming, and decision-making, and users include construction management company Parsons Brinckerhoff, the Methodist Hospital, and the US National Geospatial-Intelligence Agency (NGA).

Microsoft Tablet PC Microsoft

Microsoft Tablet PC is a term coined by Microsoft for tablet computers conforming to a set of specifications announced in 2001 by Microsoft, for a pen-enabled personal computer, conforming to hardware specifications devised by Microsoft and running a licensed copy of Windows XP Tablet PC Edition operating system or a derivative thereof.

References

  1. "Scroll". Encyclopedia.com. 2009. Retrieved 23 February 2019.
  2. JamesAGosling. "Star7 Demo" . Retrieved 8 February 2019 via YouTube.
  3. 1 2 Murano, Pietro; Sharma, Sushil (2020-02-18). "A usability evaluation of Web user interface scrolling types". First Monday. 25 (3). doi:10.5210/fm.v25i3.10309 . Retrieved 10 September 2022.
  4. Knowles, Tom (2019-04-27). "I'm so sorry, says inventor of endless online scrolling" . Retrieved 10 September 2022.
  5. "Identifying Indicators of Smartphone Addiction Through User-App Interaction". Elsevier Computers in Human Behavior. 99: 56–65. October 2019. doi:10.1016/j.chb.2019.04.023.
  6. "Designing for Digital Detox: Making Social Media Less Addictive with Digital Nudges". CHI EA '20: Extended Abstracts of the 2020 CHI Conference on Human Factors in Computing Systems: 1–9. April 2020. doi:10.1145/3334480.3382810.
  7. "PC Demoscene FAQ". tomaes.32x.de. Archived from the original on 9 December 2003. Retrieved 6 June 2022.
  8. Speed Race at the Killer List of Videogames
  9. Moto-Cross at the Killer List of Videogames
  10. Fonz at the Killer List of Videogames
  11. Road Race at the Killer List of Videogames
  12. Making the Famicom a Reality, Nikkei Electronics (September 12, 1994)
  13. "Gaming's Most Important Evolutions". GamesRadar. October 8, 2010. p. 3. Retrieved 2011-04-27.
  14. Fitzmaurice, George W. (1993-07-01). "Situated Information Spaces and Spatially Aware Palmtop Computers". Commun. ACM. 36 (7): 39–49. doi:10.1145/159544.159566. ISSN   0001-0782. S2CID   16997188.
  15. Rekimoto, Jun (1996-01-01). "Tilting Operations for Small Screen Interfaces". Proceedings of the 9th annual ACM symposium on User interface software and technology - UIST '96. Proceedings of the 9th Annual ACM Symposium on User Interface Software and Technology. UIST '96. New York, NY, USA: ACM. pp. 167–168. CiteSeerX   10.1.1.19.8330 . doi:10.1145/237091.237115. ISBN   978-0897917988. S2CID   15104495.
  16. Sharmin, Selina; Špakov, Oleg; Räihä, Kari-Jouko (2013-01-01). Reading On-screen Text with Gaze-based Auto-scrolling. Proceedings of the 2013 Conference on Eye Tracking South Africa. ETSA '13. New York, NY, USA: ACM. pp. 24–31. doi:10.1145/2509315.2509319. ISBN   9781450321105. S2CID   18759763.