Chapter 1: Introduction

image by George Hagerman, hagerman@vt.edu

1.1 Prerequisites

A working knowledge of the OpenGL graphics interface is requiured to understand the examples in this book.

1.2 What is DIVERSE?

DIVERSE stands for Device Independant Virtual Environments -- Reconfigurable, Scaleable and Extensible. DIVERSE was born at Virginia Tech in 1999, and the first release was made in the summer of 2000. The following is the official description of DIVERSE taken from the DIVERSE web page:

DIVERSE is a free (GNU LGPL and GPL) software Application Programming Interface (API) and programs. It runs on GNU/Linux and IRIX systems

DIVERSE is comprised of two components:

• The DIVERSE graphics interface for Performer (dgiPf) provides a framework to implement 3D Virtual Environment (VE) applications.
• The DIVERSE ToolKit (DTK), a separate standalone package, is used by dgiPf to provide access to local and networked VE interaction devices.

DIVERSE is designed without the "center of the universe" paradigm; you only use the parts of DIVERSE that you need, without being forced into using a particular design for your code, or having to add unneeded features.

DIVERSE provides:

• a common user interface to interactive graphics and/or VE programs.   Using DIVERSE the same program can be run on everything from a CAVE^TM to a desktop without modification.

• a common API to VE oriented hardware such as trackers, wands, joysticks and stereo glasses.

• a "remote shared memory" facility allows data from hardware or computation to be asynchronously shared between both local and remote processes

1.3 What is dgiGL?

dgiGL is an extension to DIVERSE which supports rendering with the OpenGL programming interface. Hopefully someday dgiGL will merge with DIVERSE

1.4 How does dgiGL Work?

dgiGL provides the application programmer with a simple progamming interface with which to create an OpenGL program. The application programmer stets up callbacks for the display and initialization routines (as in GLUT), and then dgiGL takes care of setting up the proper windows, viewports and projection matricies for any number of types of VE hardware. If the programmer requires a specific window or projection setup, he or she may write a display DSO which is then integrated with the program at run time.