Overview
ISO 8805:1988 defines the functional description of the Graphical Kernel System for Three Dimensions (GKS-3D). It specifies a standardized set of functions for computer graphics programming that form a basic graphics system for producing computer-generated three‑dimensional pictures on graphics output devices. The standard covers how application programs define and display 3D graphical primitives (using 3D coordinates), store and retrieve graphics from external metafiles, and generate output primitives with upward‑compatible levels of capability.
Key topics and technical requirements
- 3D graphical primitives and attributes: Definitions and mechanisms to create polylines, polymarkers, text, fill areas, cell arrays and generalized drawing primitives with associated attributes (colour, line style, text attributes, etc.).
- Coordinate systems & transformations: Normalization, view and workstation transformations; clipping and coordinate mapping between modelling, normalized and device spaces.
- Viewing and hidden surface handling: Viewing models and support for hidden line/hidden surface removal (HLHSR) identifiers.
- Workstations and device models: Workstation characteristics, selection, deferral of picture changes, clearing display space and output primitive representation across devices.
- Segments and storage: Segment model for grouping primitives, segment attributes, transformations, workstation‑independent segment storage (WISS) and clipping interactions.
- Input and interaction: Logical input device model, locator/stroke/device input modes, input queues, sample/request/event input functions and transformation of input coordinates.
- Metafile interface: GKS‑3D metafile functions for external storage and retrieval of graphical scenes.
- Levels, states and inquiry functions: Functional levels with increasing capability, system/workstation/segment state lists, inquiry and utility functions for runtime state inspection.
- Error handling and data structures: Defined error handling behaviour and standardized data structures (description tables, state lists) for implementers.
Practical applications
ISO 8805:1988 is foundational for:
- Implementing portable 3D graphics libraries and runtime systems.
- Developing CAD/CAM, CAE and scientific visualization applications that require device‑independent 3D output.
- Building graphics drivers and workstations that conform to a common functional model.
- Creating and exchanging 3D scene metafiles between tools and systems.
Who should use this standard
- Software developers and architects of graphics toolkits and rendering systems
- Device and workstation manufacturers implementing graphics output
- CAD/CAE and visualization application vendors seeking portable graphics APIs
- Standards bodies, researchers and educators in computer graphics
Related standards
- Other GKS family standards (2D/earlier GKS documents) and ISO graphics standards produced by ISO/TC 97 (Information processing systems). These offer complementary guidance for device‑independent graphics and API interoperability.
Keywords: ISO 8805:1988, GKS-3D, Graphical Kernel System, 3D graphics standard, computer graphics, workstation transformations, clipping, metafile, hidden surface removal, segments.