Overview
ISO/IEC 9636-6:1991 - "Information technology - Computer graphics - Interfacing techniques for dialogues with graphical devices (CGI) - Functional specification - Part 6: Raster" defines the raster-specific functions of the Computer Graphics Interface (CGI). It describes how CGI clients create, modify, retrieve and display image portions stored as pixel data (bitmaps), and how raster operations are controlled in a device-independent yet efficient way. Annexes A and B are integral; C–F are informative. The standard applies to Virtual Devices of class OUTPUT and OUTIN with display type RASTER.
Key topics and technical scope
- Bitmap management
- Creation and deletion of bitmaps
- Bitmap identifiers and distinction between displayable and non‑displayable bitmaps
- Bitmap types: INDEXED, DIRECT, and MIXED
- Raster control functions
- Selecting, drawing and displaying bitmaps
- Setting mapped-bitmap foreground/background colours and transparent colour
- Control of drawing modes and fill operations
- Raster operation functions
- Pixel array read/write (PIXEL ARRAY, GET PIXEL ARRAY, GET PIXEL ARRAY DIMENSIONS)
- Bitmap manipulation operations (two-operand bitblt, tile three‑operand bitblt, source-destination bitblt)
- Transparency handling, rendering in full-depth and mapped bitmaps
- Mapping and clipping
- VDC-to-device mapping and clipping rules to determine position/size of created bitmaps
- Inquiry and state
- Raster description table and raster capability inquiry (e.g., INQUIRE RASTER CAPABILITY)
- Lists of supported drawing-mode/transparency pairs and state lists for rasters and bitmaps
- Interoperability
- Specifies interactions with other parts of ISO/IEC 9636 (Parts 1–5), notably control, output, segments, input
Practical applications
ISO/IEC 9636-6:1991 is useful for:
- Graphics system and driver implementers who need a standard functional specification for raster operations and bitmap handling
- Middleware and GUI toolkit developers implementing device‑independent raster APIs
- Device vendors (displays, printers, framebuffers) ensuring consistent bitmap display and pixel manipulation
- CAD, visualization and imaging software teams that require predictable raster behaviour across hardware
- Test engineers and standards compliance teams creating conformance tests and validating raster capabilities
Related standards
Keywords: ISO/IEC 9636-6:1991, CGI, computer graphics, raster, bitmaps, pixel array, bitblt, raster operations, VDC-to-device mapping, displayable bitmap.
Open preview (PDF)Information technology — Computer graphics — Interfacing techniques for dialogues with graphical devices (CGI) — Functional specification — Part 6: Raster
