1、BRITISH STANDARD BSISO/IEC 9636-2:1991 Implementation of ISO/IEC9636-2:1991 Information technology Computer graphics Interfacing techniques for dialogues with graphical devices (CGI) Functional specification Part 2: Control UDC681.3.04(084):681.3.01BSISO/IEC9636-2:1991 This BritishStandard, having b
2、een prepared under the directionof the Information Systems Technology Standards Policy Committee, was publishedunder the authority ofthe Standards Board and comesinto effect on 15June1992 BSI02-2000 The following BSI references relate to the work on this standard: Committee referenceIST/31 Draft for
3、 comment90/62655DC ISBN 0 580 20736 6 Committees responsible for this BritishStandard The preparation of this BritishStandard was entrusted by the Information Systems Technology Standards Policy Committee (IST/-) to Technical CommitteeIST/31, upon which the following bodies were represented: Departm
4、ent of Trade and Industry (IT Standards Unit) Information Systems Committee of the Universities Funding Council Rutherford Appleton Laboratory Amendments issued since publication Amd. No. Date CommentsBSISO/IEC9636-2:1991 BSI 02-2000 i Contents Page Committees responsible Inside front cover National
5、 foreword ii Foreword v Text of ISO/IEC9636-2 1BSISO/IEC9636-2:1991 ii BSI 02-2000 National foreword This BritishStandard reproduces verbatim ISO/IEC9636-2:1991 and implements it as the UK national standard. This BritishStandard is published under the direction of the Information Systems Technology
6、Standards Policy Committee whose Technical CommitteeIST/31 has the responsibility to: aid enquirers to understand the text; present to the responsible international committee any enquiries on interpretation, or proposals for change, and keep UK interests informed; monitor related international and E
7、uropean developments and promulgate them in the UK. NOTEInternational and EuropeanStandards, as well as overseas standards, are available from BSI Sales Department, BSI, LinfordWood, MiltonKeynes, MK146LE. A British Standard does not purport to include all the necessary provisions of a contract. Use
8、rs of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, theISO/IEC title page, pages ii to vi, pag
9、es1 to36 and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.ISO/IEC9636-2:1991(E) ii BSI 02-2000 Contents Page Foreword v Introduction 1 1 Scope 1 2 Normative referenc
10、es 1 3 Concepts 2 3.1 Introduction 2 3.2 Virtual Device management 2 3.2.1 Device control 2 3.2.2 Drawing surface 2 3.2.3 Deferral mode 3 3.2.4 Serial synchronous interface 3 3.3 Coordinate space concepts 3 3.3.1 The Virtual Device coordinate system 3 3.3.2 Device coordinates 3 3.3.3 Device viewport
11、 4 3.3.4 VDC space and range 4 3.3.5 VDC extent 4 3.3.6 VDC tailoring 5 3.3.7 Drawing surface clipping 7 3.4 Error control 7 3.5 Miscellaneous control 7 3.5.1 Numerical precision requirement specifications 7 3.5.2 Escape concepts 8 3.5.3 External functions 8 3.6 Inquiry concepts 8 4 Interactions wit
12、h other parts of ISO/IEC9636 8 4.1 Interactions with more than one part of ISO/IEC9636 8 4.1.1 Virtual Device management 9 4.1.2 Coordinate space control 9 4.1.3 Error 9 4.1.4 Miscellaneous 9 5 Abstract specification of functions 9 5.1 Introduction 9 5.1.1 Control functions 9 5.1.2 Validity of retur
13、ned information 10 5.1.3 Data types employed 10 5.2 Virtual Device management functions 10 5.2.1 INITIALIZE 10 5.2.2 Terminate 10 5.2.3 EXECUTE DEFERRED ACTIONS 10 5.2.4 Deferral Mode 10 5.2.5 Prepare Drawing Surface 11 5.2.6 END PAGE 11 5.3 Coordinate space control functions 11 5.3.1 VDC Type 11 5.
14、3.2 VDC Integer Precision Requirement 11 5.3.3 VDC Real Precision Requirements 12 5.3.4 VDC Extent 12 5.3.5 Device Viewport 12 5.3.6 Device Viewport Specification Mode 13ISO/IEC9636-2:1991(E) BSI 02-2000 iii Page 5.3.7 Device Viewport Mapping 13 5.3.8 Drawing Surface Clip Rectangle 14 5.3.9 Drawing
15、Surface Clip Indicator 14 5.4 Error functions 14 5.4.1 Dequeue Error Reports 14 5.4.2 Error Handling Control 14 5.5 Miscellaneous control functions 15 5.5.1 Integer Precision Requirement 15 5.5.2 Real Precision Requirements 15 5.5.3 Index Precision Requirement 16 5.5.4 Colour Precision Requirement 1
16、6 5.5.5 Colour Index Precision Requirement 16 5.5.6 Client Specified Name Precision Requirement 17 5.5.7 MESSAGE 17 5.5.8 ESCAPE 17 5.5.9 GET ESCAPE 18 5.5.10 State List Inquiry Source 18 6 Control inquiry functions 19 6.1 Introduction 19 6.1.1 Control inquiry functions 19 6.1.2 Data types employed
17、20 6.1.3 Validity of returned information 20 6.2 Device Identity Description Table 20 6.2.1 Inquire Device Identification 20 6.3 Output Device Description Table 20 6.3.1 Inquire Device Description 20 6.4 Function and Profile Support Description Table 20 6.4.1 Lookup Function Support 20 6.4.2 Lookup
18、Profile Support 21 6.4.3 Inquire List of Profile Support Indicators 21 6.5 Control Description Table 21 6.5.1 Inquire Supported VDC Types 21 6.5.2 Inquire Device Control Capability 21 6.5.3 Lookup Escape Support 22 6.5.4 Lookup Get Escape Support 22 6.6 Control State List 22 6.6.1 Inquire Control St
19、ate 22 6.6.2 Inquire Current Precision Requirements 22 6.6.3 Inquire VDC to Device Mapping 23 6.6.4 Inquire Error Handling 23 6.6.5 Inquire Miscellaneous Control State 24 7 CGI description tables and state lists 24 7.1 Description tables 24 7.2 State lists 25 Annex A (normative) Formal Grammar of th
20、e Functional Specification 28 Annex B (normative) Control errors 36 Annex C (informative) Guidelines for CGI implementors 36ISO/IEC9636-2:1991(E) iv BSI 02-2000 Page Figure 1 An example VDC-to-Device Mapping 5 Figure 2 VDC extent establishes the reference directions relative to the drawing surface 6
21、 Table 1 Precision functions 7 Table 2 Device Identification Description Table 24 Table 3 Output Device Description Table 24 Table 4 Function and Profile Support Description Table 25 Table 5 Control Description Table 25 Table 6 Control State List 26 Descriptors: Information processing, information i
22、nterchange, graphic data processing, data handling, data transfer, interfaces, computer interfaces, specifications.ISO/IEC9636-2:1991(E) BSI 02-2000 v Foreword ISO (the International Organization for Standardization) and IEC (theInternational Electrotechnical Commission) form the specialized system
23、for worldwide standardization. National bodies that are members of ISO or IEC participate in the development of InternationalStandards through technical committees established by the respective organization to deal with particular fields of technical activity. ISO and IEC technical committees collab
24、orate in fields of mutual interest. Other international organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of information technology, ISO and IEC have established a joint technical committee, ISO/IECJTC1. Draft InternationalStandar
25、ds adopted by the joint technical committee are circulated to national bodies for voting. Publication as an InternationalStandard requires approval by at least75% of the national bodies casting a vote. InternationalStandard ISO/IEC9636-2 was prepared by Joint Technical Committee ISO/IECJTC1, Informa
26、tion technology. ISO/IEC9636 consists of the following parts, under the general title Information technology Computer graphics Interfacing techniques for dialogues with graphical devices (CGI) Functional specification: Part 1: Overview, profiles, and conformance; Part 2: Control; Part 3: Output; Par
27、t 4: Segments; Part 5: Input and echoing; Part 6: Raster. Annex A and Annex B form an integral part of this part of ISO/IEC9636. Annex C is for information only.vi blankISO/IEC9636-2:1991(E) BSI 02-2000 1 Introduction This part of ISO/IEC9636 describes the functions of the Computer Graphics Interfac
28、e concerned with Virtual Device management, coordinate space control, and error control. The functionality incorporated in this part of ISO/IEC9636 is concerned with the management of the graphics image and the interrelationship of the graphical and non-graphical parts of the interface. The function
29、ality described in this part of ISO/IEC9636 pertains to all classes of CGI Virtual Device (i.e.INPUT, OUTPUT, or OUTIN). 1 Scope This part of ISO/IEC9636 establishes those functions of the Computer Graphics Interface concerned with Virtual Device management, coordinate space control, and error contr
30、ol. The functionality incorporated in this part of ISO/IEC9636 is concerned with the management of the graphics image and the interrelationship of the graphical and non-graphical parts of the interface. This part of ISO/IEC9636 is part2 of ISO/IEC9636, and should be read in conjunction with ISO/IEC9
31、636-1 and other parts. The relationship of this part of ISO/IEC9636 to the other parts of ISO/IEC9636 is described in ISO/IEC9636-1 and in clause4. The functionality described in this part of ISO/IEC9636 pertains to all classes of CGI Virtual Device (i.e.INPUT, OUTPUT, and OUTIN). 2 Normative refere
32、nces The following standards contain provisions which, through reference in this text, constitute provisions of this part of ISO/IEC9636. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this part of ISO/IEC9636
33、are encouraged to investigate the possibility of applying the most recent editions of the standards listed below. Members of IEC and ISO maintain registers of currently valid InternationalStandards. ISO2382-13:1984, Data processing Vocabulary Part13: Computer graphics. ISO/IEC9636-1:1991, Informatio
34、n technology Computer graphics Interfacing techniques for dialogues with graphical devices (CGI) Functional specification Part1: Overview, profiles, and conformance. ISO/IEC9636-3:1991, Information technology Computer graphics Interfacing techniques for dialogues with graphical devices (CGI) Functio
35、nal specification Part3: Output. ISO/IEC9636-4:1991, Information technology Computer graphics Interfacing techniques for dialogues with graphical devices (CGI) Functional specification Part4: Segments. ISO/IEC9636-5:1991, Information technology Computer graphics Interfacing techniques for dialogues
36、with graphical devices (CGI) Functional specification Part5: Input and echoing. ISO/IEC9636-6:1991, Information technology Computer graphics Interfacing techniques for dialogues with graphical devices (CGI) Functional specification Part6: Raster. ISO/IEC9637-1:, Information technology Computer graph
37、ics Interfacing techniques for dialogues with graphical devices (CGI) Data stream binding Part1: Character encoding 1) . ISO/IEC9637-2:, Information technology Computer graphics Interfacing techniques for dialogues with graphical devices (CGI) Data stream binding Part2: Binary encoding 1) . ISO/IECT
38、R9973:1988, Information processing Procedures for registration of graphical items. 1) To be published.ISO/IEC9636-2:1991(E) 2 BSI 02-2000 3 Concepts 3.1 Introduction This part of ISO/IEC9636 defines those functions of the Computer Graphics Interface concerned with Virtual Device management, coordina
39、te space control, and error control. The functionality incorporated in this part of ISO/IEC9636 is concerned with the management of the graphics image and the interrelationship of the graphical and non-graphical parts of the interface. This functionality is divided into the following areas: Virtual
40、Device management functions, which allows the CGI client to initiate and terminate sessions of dialogue and to manage the graphics image on the Virtual Device. Coordinate space control functions, for the establishment of coordinate information, placement of the picture on the drawing surface, and fo
41、r the management of drawing surface clipping. Error control functions, which involves the detection of errors both at and subsequent to the transmission of parameters through the CGI. Miscellaneous control functions, for the establishment of data stream numeric precisions, the accessing of implement
42、ation specific functionality, and the accessing of CGI external functions. Control inquiry functions, which provide access to the description tables and state lists concerned with function and Profile support, device description, and CGI control information. 3.2 Virtual Device management 3.2.1 Devic
43、e control The CGI Virtual Device is initialized by the function INITIALIZE. The function TERMINATE sets the CGI Virtual Device in a state in which further CGI commands, other than INITIALIZE, will be ignored. It is not required that any other action take place. There are no state restrictions on the
44、 use of INITIALIZE and TERMINATE, i.e.INITIALIZE and TERMINATE may be used at any time. The Virtual Device is required to perform in conformance with ISO/IEC9636 from when the INITIALIZE function is invoked until the first TERMINATE. 3.2.2 Drawing surface Graphical output through the CGI is to a con
45、ceptual drawing surface. Physical implementations of a drawing surface may vary, but the functional capability offered by the CGI to control the drawing surface shall be the same for any implementation. Drawing surfaces are classified as being either hard-copy or soft-copy, on the basis of the mediu
46、m that implements the display surface. A drawing surface that is hard-copy is implemented by means of a medium that has to be replaced for each new image. A soft-copy drawing surface is implemented by means of a medium that may be cleared for each new image. Examples of hard-copy drawing surfaces ar
47、e found in plotter media and film for projection displays. Examples of soft-copy drawing surfaces are found in storage cathode ray tubes, cursively or raster refreshed cathode ray tubes, and in liquid crystal cells. The PREPARE DRAWING SURFACE function is used to ensure that the Virtual Device is re
48、ady to accept graphics at the start of a page or frame. The END PAGE function ensures that all output is visible and, for a hard-copy device, advances the medium if it has been marked upon. This permits the CGI client to protect the page from being overwritten by the next client to use the device, w
49、hich is of particular value in a shared peripheral environment. In some environments, the display surface is subject to spontaneous change in size or shape, for example, in window-managed environments. Whether or not such spontaneous change in display surface size or shape can occur in a given implementation is indicated by an entry in the Output Device Description Table. If such spontaneous change in size or shape information can occur in a given implementation, the device coordinate and size
