LOGICAL INPUT DEVICES IN GRAPHIGS

ŘEZNÍČEK, D.

Abstract

Portability of Graphics systems depends on interface of logical devices. The article descibes functionality of logical input devices in graphics system graPHIGS (implementation of graphics system PHIGS in the operation system AIX). Logical input device is an abstraction of one or more physical input devices which delivers logical input values to the application program. The graPHIGS supports a wide range of input devices and provides the essential tools for application interaction. The graPHIGS API supports six classes of input devices (LOCATOR, STROKE, VALUATOR, CHOICE, PICK, STRING). These classes represent generic physical devices that differ one from another by the type of data they return to the application. The graPHIGS API supports three modes of interaction (REQUEST, SAMPLE, EVENT) that allow you to request and obtain data from a logical input device.

Coresponding author e-mail: david[dot]reznicek[at]vslib[dot]cz

Session: Information Technologies in Automation