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46-458: Xwd runs in one of two ways: if a user specifies the whole screen or the name or identifier of a window as an argument, the program captures the content of the window; otherwise, it changes the shape of the cursor and waits for the user to click in a window, whose content is then captured. At the X Window core protocol level, xwd uses the fact that any X client can request the content of an arbitrary window, including ones it did not create, using

92-428: A cursor is an indicator used to show the current position on a computer monitor or other display device that will respond to input, such as a text cursor or a mouse pointer. Cursor is Latin for 'runner'. A cursor is a name given to the transparent slide engraved with a hairline used to mark a point on a slide rule . The term was then transferred to computers through analogy. On 14 November 1963, while attending

138-492: A read-only memory in some systems. Other systems allow the use of RAM for this purpose, making it possible to redefine the typeface and even the character set for application-specific purposes. The use of RAM-based characters also facilitates some special techniques, such as the implementation of a pixel-graphics frame buffer by reserving some characters for a bitmap and writing pixels directly to their corresponding character memory. In some historical graphics chips, including

184-511: A redisplay everything command, often associated with the Ctrl + L key combination. Text mode video rendering came to prominence in the early 1970s, when video-oriented text terminals started to replace teleprinters in the interactive use of computers. The advantages of text modes as compared to graphics modes include lower memory consumption and faster screen manipulation. At the time text terminals were beginning to replace teleprinters in

230-449: A conference on computer graphics in Reno, Nevada , Douglas Engelbart of Augmentation Research Center (ARC) first expressed his thoughts to pursue his objective of developing both hardware and software computer technology to augment human intelligence by pondering how to adapt the underlying principles of the planimeter to inputting X- and Y-coordinate data, and envisioned something like

276-496: A few dozen bytes for each screen update in text mode, as opposed to complex raster graphics remote procedure calls that may require the transmission and rendering of entire bitmaps . The border between text mode and graphical programs can sometimes be fuzzy, especially on the PC's VGA hardware, because many later text mode programs tried to push the model to the extreme by playing with the video controller . For example, they redefined

322-474: A limited palette of colors. These attributes can either coexist with the character indices or use a different memory area called color memory or attribute memory . Some text mode implementations also have the concept of line attributes. For example, the VT100-compatible line of text terminals supports the doubling of the width and height of the characters on individual text lines. Depending on

368-513: A program called SVGATextMode is often used with SVGA cards to set up very large console text modes, such as for use with split-screen terminal multiplexers . Many modern programs with a graphical interface simulate the display style of text mode programs, notably when it is important to preserve the vertical alignment of text, e.g., during computer programming . There exist also software components to emulate text mode, such as terminal emulators or command line consoles . In Microsoft Windows ,

414-564: A screen and select or highlight objects on the screen. In GUIs where the input method relies on hard keys, such as the five-way key on many mobile phones , there is no pointer employed, and instead, the GUI relies on a clear focus state. The pointer echoes movements of the pointing device , commonly a mouse , touchpad or trackball . This kind of pointer is used to manipulate elements of graphical user interfaces such as menus, buttons , scrollbars or any other widget . The pointer hotspot

460-448: A small left-pointing or right-pointing appendage is for indicating the direction of text flow on systems that support bi-directional text , and is thus usually known among programmers as a 'bidi cursor'. In some cases, the cursor may split into two parts, each indicating where left-to-right and right-to-left text would be inserted. In computing , a pointer or mouse pointer (as part of a personal computer WIMP style of interaction)

506-414: A text mode usually uses two distinct areas of memory . Character memory or a pattern table contains a raster font in use, where each character is represented by a dot matrix (a matrix of bits ), so the character memory could be considered as a three-dimensional bit array . Display matrix (a text buffer , screen buffer , or nametable ) tracks which character is in each cell. In the simple case

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552-469: Is r ed- g reen- b lue- a lpha , 4 or 8 stands for 16 or 256 colors, le or be is the endianness , pal is an input palette , etc. as listed by ffmpeg –pix_fmts . Details of the .xwd format in XWDFile.h depend on the platform, therefore it is unsuited for cross-platform applications and has no MIME image type. Cursor (computers) In human–computer interaction ,

598-411: Is a symbol or graphical image on the computer monitor or other display device that echoes movements of the pointing device , commonly a mouse , touchpad , or stylus pen. It signals the point where actions of the user take place. It can be used in text-based or graphical user interfaces to select and move other elements. The keyboard cursor may also be repositioned using the pointer. Though it

644-415: Is distinct from the text cursor, the mouse pointer is also being called a cursor or mouse cursor. The pointer commonly appears as an angled arrow (angled because historically that improved appearance on low-resolution screens ), but it can vary within different programs or operating systems . The use of a pointer is employed when the input method, or pointing device, is a device that can move fluidly across

690-405: Is that they assume monospaced fonts , where every character has the same width on screen, which allows them to easily maintain the vertical alignment when displaying semi-graphical characters. This was an analogy of early mechanical printers which had fixed pitch. This way, the output seen on the screen could be sent directly to the printer maintaining the same format. Depending on the environment,

736-420: Is the active pixel of the pointer, used to target a click or drag . The standard arrow pointer has the hotspot at the tip; otherwise, it is frequently in the center, though it may reside at any location in the pointer. In many GUIs, moving the pointer around the screen may reveal other screen hotspots as the pointer changes shape depending on the circumstances. For example: The I-beam pointer (also called

782-620: Is the default 80 columns by 25 rows, or 80×25, with 16 colors. This mode was available on practically all IBM and compatible personal computers. Several programs, such as terminal emulators , used only 80×24 for the main display and reserved the bottom row for a status bar . Two other VGA text modes, 80×43 and 80×50, exist but were very rarely used. The 40-column text modes were never very popular outside games and other applications designed for compatibility with television monitors, and were used only for demonstration purposes or with very old hardware. Character sizes and graphical resolutions for

828-613: Is typically used instead. In a typical text editing application , the cursor can be moved by pressing various keys. These include the four cursor keys , the Page Up and Page Down keys , the Home key , the End key , and various key combinations involving a modifier key such as the Control key . The position of the cursor also may be changed by moving the mouse pointer to a different location in

874-880: The GetImage request (this is done by the XGetImage function in the Xlib library). The content of the whole screen is obtained by requesting the content of the root window . The file generated by xwd can then be read by various other X utilities such as xwud , sxwd , xv , and the GIMP , or converted to other formats; the ImageMagick suite allows the construction of a useful pipeline : The dumps are larger in size than files in most image file formats – not only compressed formats such as PNG , but also uncompressed bitmap formats like BMP . Various image viewers and tools support

920-670: The TMS9918 , the MOS Technology VIC , and the Game Boy graphics hardware, this was actually the canonical way of doing pixel graphics. Text modes often assign attributes to the displayed characters. For example, the VT100 terminal allows each character to be underlined, brightened, blinking or inverse. Color-supporting devices usually allow the color of each character, and often the background color as well, to be selected from

966-576: The Win32 console usually opens in emulated, graphical window mode. It can be switched to full screen, true text mode and vice versa by pressing the Alt and Enter keys together. This is no longer supported by the WDDM display drivers introduced with Windows Vista. Linux virtual consoles operate in text mode. Most Linux distributions support several virtual console screens, accessed by pressing Ctrl , Alt and

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1012-584: The Windows Animated Cursor Remote Code Execution Vulnerability used a buffer overflow vulnerability to load malicious code via the animated cursor load routine of Windows. The idea of a cursor being used as a marker or insertion point for new data or transformations, such as rotation, can be extended to a 3D modeling environment. Blender , for instance, uses a 3D cursor to determine where operations such as placing meshes are to take place in

1058-408: The screen buffer can be directly addressable . Programs that display output on remote video terminals must issue special control sequences to manipulate the screen buffer. The most popular standards for such control sequences are ANSI and VT100 . Programs accessing the screen buffer through control sequences may lose synchronization with the actual display so that many text mode programs have

1104-519: The 1970s, the extremely high cost of random-access memory in that period made it exorbitantly expensive to install enough memory for a computer to simultaneously store the current value of every pixel on a screen, to form what would now be called a framebuffer . Early framebuffers were standalone devices which cost tens of thousands of dollars, in addition to the expense of the advanced high-resolution displays to which they were connected. For applications that required simple line graphics but for which

1150-488: The 3D viewport. Text mode Text mode is a computer display mode in which content is internally represented on a computer screen in terms of characters rather than individual pixels . Typically, the screen consists of a uniform rectangular grid of character cells , each of which contains one of the characters of a character set ; at the same time, contrasted to graphics mode or other kinds of computer graphics modes. Text mode applications communicate with

1196-594: The I-cursor) is a cursor shaped like a serifed capital letter I . The purpose of this cursor is to indicate that the text beneath the cursor can be highlighted and sometimes inserted or changed. Pointer trails can be used to enhance its visibility during movement. Pointer trails are a feature of GUI operating systems to enhance the visibility of the pointer. Although disabled by default, pointer trails have been an option in every version of Microsoft Windows since Windows 3.1x . When pointer trails are active and

1242-477: The X11 .xwd format, among others the GIMP , ImageMagick , Netpbm , and XnView . In version 2.1.4 FFmpeg supported pixel formats bgra, rgba, argb, abgr, rgb24, bgr24, rgb565be, rgb565le, bgr565be, bgr565le, rgb555be, rgb555le, bgr555be, bgr555le, rgb8, bgr8, rgb4_byte, bgr4_byte, pal8, gray, and monow. In these abbreviations 555 means 32768=32×32×32 colors, 565 means 65536 colors (6 bits for green), rgba

1288-466: The character set in order to create custom semi-graphical characters, or even created the appearance of a graphical mouse pointer by redefining the appearance of the characters over which the mouse pointer was shown at a given time. Text mode rendering with user-defined characters has also been useful for 2D computer and video games because the game screen can be manipulated much faster than with pixel-oriented rendering. A video controller implementing

1334-411: The cursor of a mouse he initially called a bug , which, in a 3-point form, could have a "drop point and 2 orthogonal wheels". He wrote that the "bug" would be "easier" and "more natural" to use, and unlike a stylus, it would stay still when let go, which meant it would be "much better for coordination with the keyboard." According to Roger Bates, a young hardware designer at ARC under Bill English ,

1380-452: The cursor on the screen was for some unknown reason also referred to as CAT at the time, which led to calling the new pointing device a mouse as well. In most command-line interfaces or text editors , the text cursor, also known as a caret , is an underscore , a solid rectangle, or a vertical line, which may be flashing or steady, indicating where text will be placed when entered (the insertion point ). In text mode displays, it

1426-536: The display matrix can be just a matrix of code points (so named character pointer table ), but it usually stores for each character position not only a code, but also attributes . In the case of raster scan output, which is the most common for computer monitors, the corresponding video signal is made by the character generator , a special electronic unit similar to devices with the same name used in video technology . The video controller has two registers : scan line counter and dot counter, serving as coordinates in

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1472-476: The document and clicking. The blinking of the text cursor is usually temporarily suspended when it is being moved; otherwise, the cursor may change position when it is not visible, making its location difficult to follow. The concept of a blinking cursor can be attributed to Charles Kiesling Sr. via US Patent 3531796, filed in August 1967. Some interfaces use an underscore or thin vertical bar to indicate that

1518-474: The expense of a framebuffer could not be justified, vector displays were a popular workaround. But there were many computer applications (e.g., data entry into a database) for which all that was required was the ability to render ordinary text in a quick and cost-effective fashion to a cathode-ray tube . Text mode avoids the problem of expensive memory by having dedicated display hardware re-render each line of text from characters into pixels with each scan of

1564-451: The extended VESA -compatible Super VGA text modes are manufacturer-dependent. Also on these display adapters, available colors can be halved from 16 to 8 when a second customized character set is employed (giving a total repertoire of 512 —instead the common 256— different graphic characters simultaneously displayed on the screen). Some cards (e.g. S3 ) supported custom very large text modes, like 100×37 or even 160×120. In Linux systems,

1610-492: The graphics adapter used, a variety of text modes are available on IBM PC–compatible computers. They are listed on the table below: MDA text could be emphasized with bright, underline, reverse and blinking attributes. Video cards in general are backward compatible, i.e. EGA supports all MDA and CGA modes, VGA supports MDA, CGA and EGA modes. By far the most common text mode used in DOS environments, and initial Windows consoles,

1656-401: The mouse or stylus is moved, the system waits a moment before removing the pointer image from the old location on the screen. A copy of the pointer persists at every point that the pointer has visited at that moment, resulting in a snake-like trail of pointer icons that follow the actual pointer. When the user stops moving the mouse or removes the stylus from the screen, the trails disappear and

1702-417: The paper-hungry teleprinters they were supposed to replace. Another advantage of text mode is that it has relatively low bandwidth requirements in remote terminal use. Thus, a text mode remote terminal can necessarily update the screen much faster than a graphics mode remote terminal linked to the same amount of bandwidth (and in turn will seem more responsive), since the remote server may only need to transmit

1748-521: The pointer returns to normal. Pointer trails have been provided as a feature mainly for users with poor vision and for screens where low visibility may become an issue, such as LCD screens in bright sunlight. In Windows, pointer trails may be enabled in the Control Panel , usually under the Mouse applet. Introduced with Windows NT , an animated pointer was a small looping animation that

1794-400: The screen by the cathode ray. In turn, the display hardware needs only enough memory to store the pixels equivalent to one line of text (or even less) at a time. Thus, the computer's screen buffer only stores and knows about the underlying text characters (hence the name "text mode") and the only location where the actual pixels representing those characters exist as a single unified image is

1840-400: The screen dot matrix. Each of them must be divided by corresponding glyph size to obtain an index in the display matrix; the remainder is an index in glyph matrix. If glyph size equals to 2 , then it is possible just to use n low bits of a binary register as an index in glyph matrix, and the rest of bits as an index in the display matrix — see the scheme. The character memory resides in

1886-478: The screen itself, as viewed by the user (thanks to the phenomenon of persistence of vision ). For example, a screen buffer sufficient to hold a standard grid of 80 by 25 characters requires at least 2,000 bytes. Assuming a monochrome display , 8 bits per byte, and a standard size of 8 times 8 bits for each character, a framebuffer large enough to hold every pixel on the resulting screen would require at least 128,000 bits, 16,000 bytes, or just under 16 kilobytes. By

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1932-528: The standards of modern computers, these may seem like trivial amounts of memory, but to put them in context, the original Apple II was released in 1977 with only four kilobytes of memory and a price of $ 1,300 in U.S. dollars (at a time when the minimum wage in the United States was only $ 2.30 per hour). Furthermore, from a business perspective, the business case for text terminals made no sense unless they could be produced and operated more cheaply than

1978-579: The user by using command-line interfaces and text user interfaces . Many character sets used in text mode applications also contain a limited set of predefined semi-graphical characters usable for drawing boxes and other rudimentary graphics, which can be used to highlight the content or to simulate widget or control interface objects found in GUI programs. A typical example is the IBM code page 437 character set. An important characteristic of text mode programs

2024-415: The user is in insert mode , a mode where text will be inserted in the middle of the existing text, and a larger block to indicate that the user is in overtype mode, where inserted text will overwrite existing text. In this way, a block cursor may be seen as a piece of selected text one character wide, since typing will replace the text in the cursor with the new text. A vertical line text cursor with

2070-467: Was not possible to show a vertical bar between characters to show where the new text would be inserted, so an underscore or block cursor was used instead. In situations where a block was used, the block was usually created by inverting the pixels of the character using the Boolean math exclusive or function. On text editors and word processors of modern design on bitmapped displays, the vertical bar

2116-505: Was played at the location of the pointer. This is used, for example, to provide a visual cue that the computer is busy with a task. After their introduction, many animated pointers became available for download from third party suppliers. Animated pointers are not without their problems. In addition to imposing a small additional load on the CPU, the animated pointer routines did introduce a security vulnerability . A client-side exploit known as

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