ISO/IEC INTERNATIONAL STANDARD 7942-1 Second edition 1994-11-01 Information technology Computer graphics and image processing Graphical Kernel System (GKS) Part 1: Functional description Technologies de I'information - Infographie et traitement d'image Systeme graphique GKS Partie 1: Description fonctionnelle TEC Reference number ISO/IEC7942-1:1994(E) Copyright Intemational Organization for Standardization No repr Not for Resale ISO/IEC 7942-1:1994(E) Contents Introduction .ix 1 2 Normative references. 3 Definitions. 3 4 4.1 Specification. 6 4.2 Registration 6' 5 Concepts. 5.1 Pictures... 10 5.2 Output primitive classes and attributes.. 5.3 Workstations.. 5.4 Coordinate systems and transformations. 14 5.5 Logical input devices.. ..14 5.6 Picture part store. 14 5.7 State lists. 5.8 Description tables . 14 5.9 Metafiles and archives... ..14 5.10 Routing to the backdrop ..15 5.11 Audit trail .15 5.12 Segments.... 5.13 Compatibility with ISO 7942:1985 15 5.14 6 The Graphical Kernel System ..17 6.1 Initialization. .17 6.2 Graphical output . 6.2.1 Output primitive classes 17 6.2.2 Output primitive attributes. ..17 6.3 Normalization transformations .. ..19 6.4 Picture part store .20 6.4.1 Picture part creation.... 6.4.2 Picture part functions... ..20 6.4.3 Adding picture parts .... 6.4.4 Picture part archiving.. ..20 6.5 6.5.1 Introduction ..20 6.5.2 NDC picture operations ..21 6.5.3 NDC metafiles.. ..21 6.6 Selection criterion. .21 6.7 Graphical input.... 6.7.1 Introduction to logical input devices ... 6.7.2 6.7.3 Operating modes of logical inputdevices ..24 6.7.4 Input queue and current event report... 25 ISO/IEC1994 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the publisher. ISO/IECCopyrightOffice·Casepostale56·CH-1211Geneve20·Switzerland Printed in Switzerland ii Copyright Intemational Organization for Standardization se from IHS Not for Resale ISO/IEC 7942-1:1994(E) CISO/IEC .26 6.8 Inquiry functions.. 6.9 Error handling .26 6.10 Special interfaces between GKS and the application program . .26 6.11 Backdrop.. 6.12 Audit and playback. 27 Workstation dependent control... 28 7.1 Introduction.... 7.2 Workstation characteristics .28 7.3 Selecting a workstation.. 7.4 Selection criteria.... ..29 7.5 Viewing... .30 7.6 Workstation transformations .. ..30 7.7 ..31 7.8 Colour .. 7.9 Setting representations.. .33 7.10 Removing a backdrop. 7.11 Visual effect state ..34 7.12 Realized metafile .34 7.13 Logical input devices.. ..34 7.13.1 ..34 7.13.2 Initialization of logical input devices .... 7.13.3 Definition of logical and composite input devices ....35 7.14 Sending messages to a workstation . .35 8 Output primitives . 8.1 Introduction... .36 8.2 Curve output primitives 8.2.1 Curve primitives . .36 8.2.2 Curve attributes....... .37 8.3 Marker output primitives.. .37 8.4 Area output primitives ..... .38 8.4.1 Area primitives 8.4.2 Definition of interior. .38 8.4.3 Area attributes. 8.5 Character output primitives . ..40 8.5.1 Introduction .... .40 8.5.2 Glyph specification 8.5.3 .42 8.5.4 Text extent 8.5.5 Text skewing... .43 8.5.6 .44 8.5.7 Text orientation... ...46 8.5.8 Transformed text. .47 8.5.9 Precision 8.5.10 Estimate of text extent .48 8.6 Image output primitives.. 8.7 Design output primitives. 49 8.7.1 Introduction .... .49 8.7.2 Stencils... .50 8.7.3 .52 8.7.4 Stencil composition 8.7.5 ...57 8.7.6 ii Copyright Intemational Organization for Standardization se from IHS Not for Resale ISO/IEC 7942-1:1994(E) @ISO/IEC 8.8 Generalized drawing primitive 9 Logical input device classes .. ..60 9.1 Introduction..... 9.2 Measures of eachlogical input device class.. ..60 9.3 Transformation of LOCATOR and STROKE input. 9.3.1 Transformation of LOCATOR input... 9.3.2 Transformation of STROKE input .. ...63 9.4 Prompt and echo types... 9.4.1 LOCATOR prompt a