Image rendered in MDA text mode using semigraphic blocks

Text-based semigraphics, pseudographics, or character graphics is a primitive method used in early

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'', ea ...

video hardware to emulate

raster graphics upright=1, The Smiley, smiley face in the top left corner is a raster image. When enlarged, individual pixels appear as squares. Enlarging further, each pixel can be analyzed, with their colors constructed through combination of the values for ...

without having to implement the logic for such a display mode. There are two different ways to accomplish the emulation of raster graphics. The first one is to create a low-resolution all points addressable mode using a set of special characters with all binary combinations of a certain subdivision matrix of the text mode character size; this method is referred to as block graphics, or sometimes mosaic graphics. The second one is to use special shapes instead of

glyphs A glyph ( ) is any kind of purposeful mark. In typography, a glyph is "the specific shape, design, or representation of a character". It is a particular graphical representation, in a particular typeface, of an element of written language. A ...

(letters and figures) that appear as if drawn in raster graphics mode, sometimes referred to as semi- or pseudo-graphics; an important example of this is

box-drawing characters Box-drawing characters, also known as line-drawing characters, are a form of semigraphics widely used in text user interfaces to draw various geometric frames and boxes. These characters are characterized by being designed to be connected horiz ...

. Semigraphical characters (including some block elements) are still incorporated into the

BIOS In computing, BIOS (, ; Basic Input/Output System, also known as the System BIOS, ROM BIOS, BIOS ROM or PC BIOS) is a type of firmware used to provide runtime services for operating systems and programs and to perform hardware initialization d ...

of any

VGA Video Graphics Array (VGA) is a video display controller and accompanying de facto graphics standard, first introduced with the IBM PS/2 line of computers in 1987, which became ubiquitous in the IBM PC compatible industry within three years. T ...

compatible video card, so any PC can display these characters from the moment it is turned on, even when no operating system is yet loaded. Single and double lines are still often drawn with this method when the system uses text mode; for example when running the BIOS setup program. Many of these historical ideas have been adopted into

Unicode Unicode or ''The Unicode Standard'' or TUS is a character encoding standard maintained by the Unicode Consortium designed to support the use of text in all of the world's writing systems that can be digitized. Version 16.0 defines 154,998 Char ...

, in, for example in the

Symbols for Legacy Computing Symbols for Legacy Computing is a Unicode block containing graphic characters that were used for various home computers from the 1970s and 1980s and in teletext broadcasting standards. It includes characters from the Amstrad CPC, MSX, Mattel Aqua ...

Block Elements Block Elements is a Unicode block containing square block symbols of various fill and shading. Used along with block elements are box-drawing characters, shade characters, and terminal graphic characters. These can be used for filling regions of t ...

Box Drawing Box Drawing is a Unicode block containing characters for compatibility with legacy graphics standards that contained characters for making bordered charts and tables, i.e. box-drawing characters. Its block name in Unicode 1.0 was Form and Chart C ...

and

Geometric Shapes A shape is a graphics, graphical representation of an object's form or its external boundary, outline, or external Surface (mathematics), surface. It is distinct from other object properties, such as color, Surface texture, texture, or material ...

Unicode block A Unicode block is one of several contiguous ranges of numeric character codes (code points) of the Unicode character set that are defined by the Unicode Consortium for administrative and documentation purposes. Typically, proposals such as the ...

Block graphics

For example, an 8×12 pixel character could be divided vertically in two halves and horizontally in three parts, and then assigning "ink" and "background" values to the elements of the matrix in a binary pattern, corresponding to the binary sequence of the position in the font table of a 2×3 ''block mosaic'' matrix of so-called ''squots'' (square dots) or ''sextants''. Less often used versions use a 1×6 "matrix", in which case these six "pixels" are sometimes referred to as

sixel Sixel, short for "six pixels", is a bitmap graphics format supported by terminals and printers from DEC. It consists of a pattern six pixels high and one wide (in black and white), resulting in 64 possible patterns. Each possible pattern is a ...

s. But dividing an 8×8 character in 2×2 "pixels" called ''quadrants'' was also common (it was, for example, used in the Sinclair ZX81). Sometimes the text semigraphical characters are simply incorporated into the systems font-set, sometimes special video hardware is used to directly convert the bit-pattern from video memory into the pixels. In rare cases a character matrix was not dividable vertically by three, for example in an 8×8 matrix the mosaic is sometimes divided so that it uses a 3:2:3 scan line scheme. The Galaksija's graphics mode is an example, although with a 4:5:4 scheme the distortion effect was minimal. The seminal use of this technology was in the

TRS-80 The TRS-80 Micro Computer System (TRS-80, later renamed the Model I to distinguish it from successors) is a desktop microcomputer developed by American company Tandy Corporation and sold through their Radio Shack stores. Launched in 1977, it is ...

where the only way to get discrete pixels on the screen that could be turned on and off individually, (all points addressable) was by the use of a 2×3 pixel matrix of block graphics. In the case of the TRS-80 these block graphics were not incorporated into a font ROM, as later became the norm, but were generated directly from the logic pattern of six bits from the video RAM using a dedicated circuit made from

logic gate A logic gate is a device that performs a Boolean function, a logical operation performed on one or more binary inputs that produces a single binary output. Depending on the context, the term may refer to an ideal logic gate, one that has, for ...

s. An earlier system using the same pseudo-graphics array of a 2 by 3 matrix was the Video Terminal Interface (VTI) of the

Poly-88 PolyMorphic Systems was a manufacturer of microcomputer boards and systems based on the S-100 bus. Their products included the Poly-88 and the System 8813. The company was incorporated in California in 1976 as Interactive Products Corporation d/ ...

polymorphic systems PolyMorphic Systems was a manufacturer of microcomputer boards and systems based on the S-100 bus. Their products included the Poly-88 and the System 8813. The company was incorporated in California in 1976 as Interactive Products Corporation Do ...

, an

S-100 bus The S-100 bus or Altair bus, later standardized as IEEE 696-1983 ''(inactive-withdrawn)'', is an early computer bus designed in 1974 as a part of the Altair 8800. The bus was the first industry standard expansion bus for the microcomputer in ...

based system predating the TRS-80. If the system also supported color, the color resolution of the resulting pixels was normally equal to the text resolution, often leading to

attribute clash Attribute clash (also known as colour clash or bleeding) is a display Visual artifact, artifact caused by limits in the graphics circuitry of some colour 8-bit home computers, most notably the ZX Spectrum, where it meant that only two colours ...

as the color of a pixel could not be changed on a per pixel basis, but only to one "ink", and one "background" color for all pixels within a character position. Sometimes the number of characters in the font, dedicated to block graphics, could be halved if the system also supported an "invert" attribute, as half the characters in a full block graphics font set are the logical inverse of the other half of the font set. Other tricks that were used to decrease the number of needed characters, was to use a space for the "all bits are zero" character, and to use character 7F hex for the "all bits are on" character, as character 7F hex (decimal 127) was often defined as an "all pixels on" character (this was because when using

papertape Five- and eight-hole wide punched paper tape Paper tape reader on the Harwell computer with a small piece of five-hole tape connected in a circle – creating a physical program loop Punched tape or perforated paper tape is a form of data st ...

punching out all seven holes, created the 7F hex "byte" which was considered to be the "DEL" or "rub-out" character). The assignment in

ASCII ASCII ( ), an acronym for American Standard Code for Information Interchange, is a character encoding standard for representing a particular set of 95 (English language focused) printable character, printable and 33 control character, control c ...

of the rub-out character (to the code point 127) led designers of VDUs to use "rub-out" for a character square filled with "ink", which was often used to represent the cursor.

Examples of the use of block graphics

Other examples of systems that relied on the use of block graphics are: * The

ZX80 The Sinclair ZX80 is a home computer launched on 29 January 1980 by Science of Cambridge Ltd. (later to be better known as Sinclair Research). It is notable for being one of the first computers available in the United Kingdom for less than a hu ...

and

ZX81 character set The ZX81 character set is the character encoding used by the Sinclair Research ZX81 family of microcomputers including the Timex Sinclair 1000 and Timex Sinclair 1500. The encoding uses one byte per character for 256 code points. It has no relatio ...

s, where a matrix of 2×2 pixels was used, with the space and invert attribute tricks to keep the number of characters in the ROM needed down to just 7 (of the necessary 16). The

ZX Spectrum The ZX Spectrum () is an 8-bit computing, 8-bit home computer developed and marketed by Sinclair Research. One of the most influential computers ever made and one of the all-time bestselling British computers, over five million units were sold. ...

also supported block graphics as well as "real" higher-resolution graphics. In addition, on the Spectrum the system font (stored in its ROM) could be easily and instantly changed to one stored in RAM, allowing programmers to define their own semigraphical characters to suit their needs. * Other systems that used a 2×2 matrix included the Panasonic JR-200 and the

Mattel Aquarius The Aquarius is a home computer designed by ''Radofin'' and released by ''Mattel Electronics'' in 1983. Based on the Zilog Z80 microprocessor, the system has a rubber chiclet keyboard, 4 kB of RAM, and a subset of Microsoft BASIC in ROM. It conn ...

. The latter supported not just 2×2 matrix semigraphics but also 2×3 matrix semigraphics, albeit imperfectly, as the semigraphics pixels in a character's middle row were less tall than those in the top and bottom rows, due to imperfect division of the 8×8 pixel character matrix. * The

Commodore PET The Commodore PET is a line of personal computers produced starting in 1977 by Commodore International. A single all-in-one case combines a MOS Technology 6502 microprocessor, Commodore BASIC in read-only memory, keyboard, monochrome monitor ...

also had a few characters to support 2×2 text semigraphics in its

PETSCII PETSCII (PET Standard Code of Information Interchange), also known as CBM ASCII, is the character set used in Commodore Business Machines' 8-bit home computers. This character set was first used by the PET from 1977, and was subsequently use ...

character set. The PET was also one of the first systems to rely heavily on semigraphical characters, to get any form of graphics on screen. * The

TRS-80 Color Computer The RadioShack TRS-80 Color Computer, later marketed as the Tandy Color Computer, is a series of home computers developed and sold by Tandy Corporation. Despite sharing a name with the earlier TRS-80, the Color Computer is a completely different ...

, and the

Dragon 32/64 The Dragon 32 and Dragon 64 are 8-bit home computers that were built in the 1980s. The Dragons are very similar to the TRS-80 Color Computer, and were produced for the European market by Dragon Data, Ltd., initially in Swansea, Wales, before mo ...

are good examples of systems using 2×2 matrix color semigraphics. But their

Motorola 6847 The MC6847 is a Video Display Generator (VDG) first introduced by Motorola in 1978 and used in the TRS-80 Color Computer, Dragon 32/64, Laser 200, TRS-80 MC-10/ Matra Alice, NEC PC-6000 series, Acorn Atom, Gakken Compact Vision TV Boy an ...

VDC also supported a little used 6-block semigraphics mode. *

Videotex Videotex (or interactive videotex) was one of the earliest implementations of an end-user information system. From the late 1970s to early 2010s, it was used to deliver information (usually pages of text) to a user in computer-like format, typi ...

and

teletext Teletext, or broadcast teletext, is a standard for displaying text and rudimentary graphics on suitably equipped television sets. Teletext sends data in the broadcast signal, hidden in the invisible vertical blanking interval area at the to ...

systems used a 2×3 matrix and one foreground ("ink"), and one background color, normally out of a set of eight colors (including black and white). Many systems used " Videotex graphics". One of the best known examples is the Acorn

BBC Micro The BBC Microcomputer System, or BBC Micro, is a family of microcomputers developed and manufactured by Acorn Computers in the early 1980s as part of the BBC's Computer Literacy Project. Launched in December 1981, it was showcased across severa ...

's default graphics mode ( mode 7). Other systems which used "Videotex"-like graphics are: the

ABC 80 The ABC 80 (Advanced BASIC Computer 80) is a home computer engineered by the Swedish corporation Dataindustrier AB (DIAB) and manufactured by Luxor in Motala, Sweden in the late 1970s and early 1980s. It was introduced on the market in August 1 ...

, the Grundy NewBrain, many of the

Acorn Eurocard systems The Acorn System was a series of modular microcomputer systems based on rack-mounted Eurocards developed by Acorn Computers from 1979 to 1982, aimed primarily at industrial and laboratory use, but also home enthusiasts. The experience gained in ...

, and the Philips P2000T, which actually used a

Teletext Teletext, or broadcast teletext, is a standard for displaying text and rudimentary graphics on suitably equipped television sets. Teletext sends data in the broadcast signal, hidden in the invisible vertical blanking interval area at the to ...

chip designed for their TV's. * The

Matra Alice The Matra & Hachette Ordinateur Alice is a home computer sold in France beginning in 1983. It was a clone of the TRS-80 MC-10, produced through a collaboration between Matra and Hachette in France and Tandy Corporation in the United States. ...

32, Matra Alice 90 and

Philips VG5000 The VG5000μ is a computer created by Philips in 1984. It was manufactured in Le Mans by Radiotechnique (RTS) and marketed under the Philips, Radiotechnique, Radiola and Schneider Rundfunkwerke, Schneider brands. Not compatible with any other mach ...

were based on the

Thomson EF9345 The EF9345 from SGS-Thomson Microelectronics, Inc., was a semigraphic single chip microprocessor for video image control, encapsulated in a 40-pin DIP and used primarily in the Matra Alice 32, Matra Alice 90 and Philips VG5000 microcomputers. It ...

graphic chip, only capable of displaying

alphanumeric Alphanumericals or alphanumeric characters are any collection of number characters and letters in a certain language. Sometimes such characters may be mistaken one for the other. Merriam-Webster suggests that the term "alphanumeric" may often ...

and semigraphic characters. * The PC-8001 managed to combine normal text with a full set of 256 text semigraphical "characters" in a 2×4 matrix; the system distinguished the set of 256 semigraphics patterns from the 256-character set used for "normal" fonts via character attribute bytes.PC-8801 Programing - VRAM Information
(Source in Japanese; the relevant sentence is "アトリビュートに開始位置とセミグラフィック指定ビット=1 を立てて、テキスト VRAM には文字コードの代わりにドットパターンを書き込みます。" This roughly translates to ''"At the starting position of semigraphics mode, once the relevant attribute bit is set to one, a dot pattern will be written to the VRAM for the character code instead f the default graphical letter"'') * One of the last video systems where text semigraphics were a useful option was the

Color Graphics Adapter The Color Graphics Adapter (CGA), originally also called the ''Color/Graphics Adapter'' or ''IBM Color/Graphics Monitor Adapter'', introduced in 1981, was IBM's first color graphics card for the IBM PC and established a De facto standard, de fac ...

(CGA). This graphics adapter for early

IBM-PC The IBM Personal Computer (model 5150, commonly known as the IBM PC) is the first microcomputer released in the IBM PC model line and the basis for the IBM PC compatible ''de facto'' standard. Released on August 12, 1981, it was created by a ...

s only supported four colors in its high-resolution graphics mode, but in text mode it could display 16 different colors. Although the CGA adapter's font ROM did not contain all of the otherwise typical text semigraphics characters, it was still possible to create a 160 × 100 CGA text semigraphics mode using a semi-documented trick.

Semigraphical characters

Semigraphical characters are also characters in a font that are intended to give the impression that a system can support high resolution graphics, while in fact the system operates in text mode. Characters such as

box-drawing character Box-drawing characters, also known as line-drawing characters, are a form of semigraphics widely used in text user interfaces to draw various geometric frames and boxes. These characters are characterized by being designed to be connected horiz ...

s, circles and dots, card symbols like ♠, ♣, ♥ and ♦, and "graphical building block"

geometric shapes A shape is a graphics, graphical representation of an object's form or its external boundary, outline, or external Surface (mathematics), surface. It is distinct from other object properties, such as color, Surface texture, texture, or material ...

such as triangles gave such systems that appearance. One of the first systems that used such characters, the canonical example that others followed, was the

, which had many of them within its

font set. The original PET relied to such a degree on these characters that it printed them on its keyboard, as can be seen here, an example that other systems soon copied. Another good example of a system that relied on semigraphical characters is the venerable Sharp MZ80K, which had no high-resolution graphics, nor reprogrammable characters, but relied fully on an extended font set with many pseudo graphical characters. With these it was still possible to generate games that looked like the system had high-resolution graphics. Some of the systems that had a programmable font set, but did not have a real high resolution raster graphics hardware, came with default character sets to be uploaded in character set RAM, and these sets often incorporated the ideas mentioned here, although it was often also the case that dedicated semigraphical characters were defined as needed.

Systems that relied on semigraphical characters

Examples of systems that relied heavily on semigraphical characters for their graphics are: * The original

IBM PC The IBM Personal Computer (model 5150, commonly known as the IBM PC) is the first microcomputer released in the List of IBM Personal Computer models, IBM PC model line and the basis for the IBM PC compatible ''de facto'' standard. Released on ...

with the MDA offered no form of graphics other than the

of its default hardware code page

437 __NOTOC__ Year 437 ( CDXXXVII) was a common year starting on Friday of the Julian calendar. At the time, it was known as the Year of the Consulship of Aetius and Sigisvultus (or, less frequently, year 1190 ''Ab urbe condita''). The denominati ...

. * The

was one of the first systems to rely heavily on semigraphical characters, to get any form of graphics on screen (see

). * The

Sinclair Sinclair may refer to: Places * Lake Sinclair, near Milledgeville, Georgia * Mount Sinclair, Canada * Sinclair, Iowa * Sinclair, West Virginia * Sinclair, Wyoming * Sinclair Mills, British Columbia * Sinclair Township, Minnesota * Sincl ...

and

ZX81 The ZX81 is a home computer that was produced by Sinclair Research and manufactured in Dundee, Scotland, by Timex Corporation. It was launched in the United Kingdom in March 1981 as the successor to Sinclair's ZX80 and designed to be a low-c ...

relied on block graphics characters for a low-resolution graphics of 64×48 pixels black-and-white or 32×48 in black, white, and

dither Dither is an intentionally applied form of noise used to randomize quantization error, preventing large-scale patterns such as color banding in images. Dither is routinely used in processing of both digital audio and video data, and is ofte ...

ed gray as seen in the

ZX80 character set The ZX80 character set is the character encoding used by the Sinclair Research ZX80 microcomputer with its original 4K Sinclair BASIC, BASIC Read-Only Memory, ROM. The encoding uses one byte per character for 256 code points. It has no relationshi ...

and

. * The

relied completely on its character set for games, even though it was marketed through toy-shops. It never became a commercial success partly because of this limitation, which was outdated at the time (see Mattel Aquarius character set). * The Panasonic JR-200 also used semigraphical characters in combination with block graphics (see Matsushita JR series character set). * The

Sharp MZ The Sharp MZ is a series of personal computers sold in Japan and Europe (particularly Germany and Great Britain) by Sharp Corporation, Sharp beginning in 1978. History Although commonly believed to stand for "Microcomputer Zilog Z80, Z80", t ...

series of computers offered no high resolution or programmable characters, but did have a very complete set of semigraphical characters (see Sharp MZ character set). - and so still offered many visually nice games. * The

32 and 90; and the

(see Thomson EF9345 character set). * The

Compukit UK101 The Compukit UK101 microcomputer (1979) is a kit clone of the Ohio Scientific Superboard II single-board computer, with a few enhancements for the UK market - notably replacing the 24×24 (add guardband kit to give 32×32) screen display with ...

(clone of the popular Ohio Scientific superboard) also was a very early system that relied on its 256 characters set. * The text modes of later Apple II computers, beginning with the

Apple IIc The Apple IIc is a personal computer introduced by Apple Inc. shortly after the launch of the Macintosh 128K, original Macintosh in 1984. It is essentially a compact and portable version of the Apple IIe. The IIc has a built-in floppy disk driv ...

and the enhanced version of the

Apple IIe The Apple IIe (styled as Apple //e) is the third model in the Apple II series of personal computers produced by Apple Inc., Apple Computer. It was released in January 1983 as the successor to the Apple II Plus. The ''e'' in the name stands for ...

, supported the

MouseText MouseText is a set of 32 graphical characters designed by Bruce Tognazzini and first implemented in the Apple IIc. They were then retrofitted to the Apple IIe forming part of the Enhanced IIe upgrade. A slightly revised version was then released w ...

character set, which replaced flashing uppercase characters when enabled. Although these Apple systems did not rely on these character sets they did play a role in simulating GUI like graphics of their more advanced family members, while still in text mode.

References

{{reflist, refs= {{cite book , title=Proposal to add characters from legacy computers and teletext to the UCS , chapter=5. Graphic characters , work=Universal Multiple-Octet Coded Character Set , publisher=Terminals Working Group (TWG),

International Organization for Standardization The International Organization for Standardization (ISO ; ; ) is an independent, non-governmental, international standard development organization composed of representatives from the national standards organizations of member countries. M ...

, author-first1=Doug , author-last1=Ewell , author-link1=Doug Ewell , author-first2=Rebecca G. , author-last2=Bettencourt , author-link2=Rebecca G. Bettencourt , author-first3=Ricardo , author-last3=Bánffy , author-first4=Michael , author-last4=Everson , author-link4=Michael Everson , author-first5=Eduardo Marín , author-last5=Silva , author-first6=Elias , author-last6=Mårtenson , author-first7=Mark , author-last7=Shoulson , author-first8=Shawn , author-last8=Steele , author-first9=Rebecca , author-last9=Turner , date=2019-01-04 , id=L2/19-25 , page=3 , url=http://www.unicode.org/L2/L2019/19025-terminals-prop.pdf , access-date=2021-01-11 , url-status=live , archive-url=https://web.archive.org/web/20201224013239/https://www.unicode.org/L2/L2019/19025-terminals-prop.pdf , archive-date=2020-12-24 , quote-page=3 , quote=The word "sextant" is used in this document, by analogy with "quadrant"—a term used for certain UCS characters since 1999—to refer to a semigraphics block consisting of six smaller blocks or "cells" arranged in two columns and three rows. In the teletext specification, characters in this group could be displayed either with the cells joined together, as with the existing quadrant characters, or with a narrow space between cells. A teletext emulator could interpret the control character U+001A ("separated graphics") to display space between cells, or U+0019 ("contiguous graphics") to revert to the default, joined appearance {{cite web , author-first=Ira , author-last=Goldklang , date=2015 , title=Graphic Tips & Tricks , url=http://www.trs-80.com/wordpress/zaps-patches-pokes-tips/graphics/ , access-date=2017-07-29 , url-status=live , archive-url=https://web.archive.org/web/20170729202445/http://www.trs-80.com/trs80-zaps-hardware-model4.htm , archive-date=2017-07-29 {{Cite web, url=http://jayceland.com/LunchNStuff/Archives/2002905.html, title=JayceLand's Weekly Rochester Events #191: All White Sixel, website=jayceland.com {{Cite web , url=http://www.old-computers.com/museum/software.asp?t=2&c=330&st=1 , title=OLD-COMPUTERS.COM Museum ~ GALAKSIJA Galaksija software & screenshots , access-date=2014-01-27 , at=See the second image from above. The image shows small difference in height of some "pixel"s. {{Cite web, url=http://www.old-computers.com/museum/doc.asp?c=409&st=1, title=Description of TRS-80 block graphics Technical details ZX-81 character set and block graphics
/ref> {{Cite web, url=http://www.cs.unc.edu/~yakowenk/coco/text/semigraphics.html, title=CoCo Semi-graphics-6 display mode {{Cite web, url=http://www.bbcbasic.co.uk/bbcwin/manual/bbcwinh.html, title=R.T.Russell: BBC BASIC for Windows, website=www.bbcbasic.co.uk {{Citation , year=1983 , title=IBM PC XT Technical Reference , publisher=IBM , url=https://archive.org/details/IBMPCXTTechnicalReference1502237 , at=p. 1-142 , access-date=2018-08-24 {{Citation , year=1983 , title= Commodore C64 Manual: Commodore 64 Programmers Reference Guide , publisher=Commodore , page=379 , url=https://archive.org/details/Commodore_64_Programmers_Reference_Guide_1983_Commodore , access-date=2018-08-24 {{Cite web, url=http://www.old-computers.com/museum/computer.asp?c=174, title=old-computers.com Entry on the Sharp MZ80K mentions the lack of graphics capabilities {{Cite web, url=https://www.youtube.com/watch?v=MgBQH2PLHs4, title=Sharp MZ80K - BASE ZERO game., date=29 January 2010 , via=www.youtube.com {{Cite web, url=https://www.vdsteenoven.com/aquarius/, title=Mattel Aquarius Homecomputer system, website=www.vdsteenoven.com {{Cite web, url=http://old-computers.com/museum/software.asp?c=174&st=1, title=Games on the MZ-80K relied on its great set of semigraphical characters Computer graphic techniques Character sets Computer graphics data structures Graphics file formats Videotex

Block graphics

Examples of the use of block graphics

Semigraphical characters

Systems that relied on semigraphical characters

See also

References