VAX LISP/VMS Graphics Programming Guide

This document, the "VAX LISP/VMS Graphics Programming Guide" (Order Number: AA-GH76A-TE, May 1986) from Digital Equipment Corporation, serves as a comprehensive manual for LISP language programmers. Its primary purpose is to provide the necessary information for writing programs that utilize the VAX LISP interface to VAXstation graphics, specifically on VAXstation II under VAX/VMS Version 4.2 (and VAX LISP/VMS Version 2.0).

The guide is divided into two main parts:

1. Part I: Guide to Graphics Programming (Tutorial): This section introduces the VAX LISP graphics system and provides a conceptual and practical understanding of its capabilities. Key topics include:

   • Virtual Displays and Windows: Explains how graphic information is stored and displayed, covering coordinate systems (World, Device, Screen), creation and manipulation of virtual displays, windows, and viewports, and handling user actions like window movement and resizing.
   • Graphics Output Operations: Details functions for drawing lines, shapes (circles, ellipses), and text. It extensively covers "attributes" and "attribute blocks" which control the appearance of graphical output (e.g., color, line style, writing mode, fonts, clipping). It also introduces "segments" for temporary attribute changes and how to move and erase graphic information.
   • Screen Images and Bitmaps: Describes how to read screen images into memory, manipulate them as "bitmap arrays" (using the BITBLT function), and write them back to the screen or store them in files.
   • Pointer Operations: Explains how to use pointing devices (like a mouse) for input, including obtaining and setting pointer position, responding to pointer movement within defined areas, and handling button input.
   • Keyboard Input: Covers the use of "virtual keyboards" to capture keystrokes, either synchronously or asynchronously, and how to associate keyboards with windows.
   • Window Output Streams: Describes how to direct standard LISP text output to a window, including options for text wrapping, scrolling, and controlling text appearance.

2. Part II: Graphics System Components (Reference): This section serves as an alphabetical reference for all specific functions, macros, and data types (such as DISPLAY, WINDOW, TRANSFORMATION, and KEYBOARD objects) within the VAX LISP graphics system, detailing their formats, arguments, and return values.

The document is intended for programmers already familiar with VAX LISP and the VAXstation environment.