PENCIL(ID:451/pen001)Pictorial encoding languagePictorial ENCodIng Language. On-line system to display line structures. Extension to the MULTILANG on-line programming system Related languages
References: in [AFIPS] Proceedings of the 1967 Spring Joint Computer Conference, April 18-20, Atlantic City, N. J. SJCC 30 view details techniques, thereby reducing the time required to imple- ment the language. Although the syntax of one-dimen- sional languages is not a natural medium for two-di- mensional problems, it is at present the only practical technique for making progress with graphic languages. Abstract: Interactive use of computers with graphic terminals will permit many new problems to be solved using machines. In order to handle a variety of applications, it is expedient to develop a general purpose graphic language that is useful on a number of graphic devices. A system has been designed to produce such a language quickly and cheaply. A model graphic language which has been developed with the system is presented. in [ACM] CACM 11(04) (April 1968) view details in [ACM] CACM 11(04) (April 1968) view details in Computers & Automation 21(6B), 30 Aug 1972 view details The exact number of all the programming languages still in use, and those which are no longer used, is unknown. Zemanek calls the abundance of programming languages and their many dialects a "language Babel". When a new programming language is developed, only its name is known at first and it takes a while before publications about it appear. For some languages, the only relevant literature stays inside the individual companies; some are reported on in papers and magazines; and only a few, such as ALGOL, BASIC, COBOL, FORTRAN, and PL/1, become known to a wider public through various text- and handbooks. The situation surrounding the application of these languages in many computer centers is a similar one. There are differing opinions on the concept "programming languages". What is called a programming language by some may be termed a program, a processor, or a generator by others. Since there are no sharp borderlines in the field of programming languages, works were considered here which deal with machine languages, assemblers, autocoders, syntax and compilers, processors and generators, as well as with general higher programming languages. The bibliography contains some 2,700 titles of books, magazines and essays for around 300 programming languages. However, as shown by the "Overview of Existing Programming Languages", there are more than 300 such languages. The "Overview" lists a total of 676 programming languages, but this is certainly incomplete. One author ' has already announced the "next 700 programming languages"; it is to be hoped the many users may be spared such a great variety for reasons of compatibility. The graphic representations (illustrations 1 & 2) show the development and proportion of the most widely-used programming languages, as measured by the number of publications listed here and by the number of computer manufacturers and software firms who have implemented the language in question. The illustrations show FORTRAN to be in the lead at the present time. PL/1 is advancing rapidly, although PL/1 compilers are not yet seen very often outside of IBM. Some experts believe PL/1 will replace even the widely-used languages such as FORTRAN, COBOL, and ALGOL.4) If this does occur, it will surely take some time - as shown by the chronological diagram (illustration 2) . It would be desirable from the user's point of view to reduce this language confusion down to the most advantageous languages. Those languages still maintained should incorporate the special facets and advantages of the otherwise superfluous languages. Obviously such demands are not in the interests of computer production firms, especially when one considers that a FORTRAN program can be executed on nearly all third-generation computers. The titles in this bibliography are organized alphabetically according to programming language, and within a language chronologically and again alphabetically within a given year. Preceding the first programming language in the alphabet, literature is listed on several languages, as are general papers on programming languages and on the theory of formal languages (AAA). As far as possible, the most of titles are based on autopsy. However, the bibliographical description of sone titles will not satisfy bibliography-documentation demands, since they are based on inaccurate information in various sources. Translation titles whose original titles could not be found through bibliographical research were not included. ' In view of the fact that nany libraries do not have the quoted papers, all magazine essays should have been listed with the volume, the year, issue number and the complete number of pages (e.g. pp. 721-783), so that interlibrary loans could take place with fast reader service. Unfortunately, these data were not always found. It is hoped that this bibliography will help the electronic data processing expert, and those who wish to select the appropriate programming language from the many available, to find a way through the language Babel. We wish to offer special thanks to Mr. Klaus G. Saur and the staff of Verlag Dokumentation for their publishing work. Graz / Austria, May, 1973 in Computers & Automation 21(6B), 30 Aug 1972 view details in Computers & Automation 21(6B), 30 Aug 1972 view details in Computers & Automation 21(6B), 30 Aug 1972 view details Historically SKETCHPAD (Sutherland) was the first widely recognized general purpose graphics system. The SKETCHPAD system consists of a collection of subroutines called interactively through a menu selection process. The system allows pictures to be constructed hierarchically from other pictures and is noted for its use of a ring data structure to store picture descriptions. Kulsrud, Williams, and Giloi presented models for the definition of a general purpose graphics language, Kulsrud suggested that the first version of the proposed language have written commands and that it later be adjusted to accept input from graphics devices such as light pens and trackballs. The language she described was capable of picture description, manipulation, and analysis. Although it could be used with interactive applications programs, it was not an interactive language. Williams described a language that provided (i) data types with related operations particularly suited to graphical applications, and (2) the ability to add new data types and operations. For example, a "point,' could be a data type, and a specially defined addition operator would operate on that data type. The language was thus highly extensible, but it was not interactive. Giloi proposed a model to be used in constructing either subroutine packages for graphic display applications or graphical extensions to existing languages. In this model, pictures were described as a hierarchy of subpictures and picture primitives. Primitives were defined as anything for which there was a hardware generator in the display processor, placing limits on the device independence of a language developed from his model. An interactive version of the model was developed by extending APL to include graphics capabilities, and a non-interactive version was developed as a FORTRAN subroutine package. The general purpose graphics systems presented in recent years can be classified as (i) subroutine packages for graphics applications, (2) graphics extensions to existing languages, and (3) new languages possessing graphics capabilities. Graphics subroutine packages are most widely distributed particularly by manufacturers of graphics display hardware. Some example packages are GINO-F, GPGS, GRAF, DISSPLA, and EXPLOR. Most packages are limited to the manipulation of picture displays with few programming control or storage capabilities. Where such abilities are available they often serve specialized purposes as in WAVE, a package for waveform analysis. One exception is the VIP system where the user is able to combine the available system function subroutines into special purpose functions which can then be used in the same way that the original system functions were used. Extensions of an existing language such as Euler-G, IMAGE, APLBAGS, APLG, and PENCIL, provide a programmer with graphics capabilities as well as general programming features. Euler-G has excellent data structure definition facilities. IMAGE, an extension of FORTRAN, cannot provide the data structure description capabilities that are available in Euler-G, but it has the advantage of being based on the most widely distributed host language available. APLBAGS, APLG, and PENCIL, an extension of the MULTILANG on-line programming system, are truly conversational languages. GRASP, a PL/I extension, is a compiled language but it allows dynamic interaction. GRASP also allows the definition of models from which complex pictures can be created hierarchically. ESP3, an extension of SNOBOL4, is a non-interactive language from which many of the high-level concepts found in PIGLI are drawn. Language extensions are found mainly in experimental installations. Two complete graphics languages are METAVISU and GLIDE. Both take characteristics from a base language (PL/I and ALGOL, respectively) and add capabilities for defining, displaying, and manipulating pictures. Full languages are less widely distributed than subroutine packages or language extensions. in Proceedings of the 1978 annual conference 1978, Washington, D.C., United States view details |