Introduction

At the turn of the century, someone defined an inventor as a person who makes an ingenious arrangement of wheels, levers and springs, and believes it civilization. Now, nearly a hundred years later, it could be said that an inventor is a person who concocts an ingenious arrangement of computer code and believes it intuitive. Since everyone's intuition has its off-days, the IRIS Explorer User's Guide provides a few tips for using IRIS Explorer(tm), a decidedly ingenious arrangement.

IRIS Explorer is a system for creating powerful application maps, each of which comprises a series of small software tools, called modules. A map is a collection of modules that carries out a series of related operations on a dataset and produces a result. IRIS Explorer applications are usually, but not exclusively, concerned with visualisation.

IRIS Explorer has three main components:


The IRIS Explorer System

To understand how these components interact in the system, think of a factory. The purpose of a factory is to take raw materials and fashion them into an end product, according to a specific design. The raw materials are fed into an assembly line at one end, go through a number of alterations and manipulations as they pass through the machines on the factory floor, and then come out at the other end in the form of a finished product. The product is inspected for the qualities stipulated in the design. If they are not present, or not satisfactory, the machines on the floor can be adjusted until the quality of the product meets requirements.

The factory floor is not the only important area in a factory. To make products, the machines need raw materials that are suitable for the task at hand. The materials may be delivered in usable condition, or they may need processing to get them into a form that the machines can accept. So the materials controller is important.

The factory also needs machines, a different one for each process that takes place on the floor. Some machines may be standard models, but for certain tasks, the factory needs custom-built machines. The machine shop, then, is also very important.

The way in which IRIS Explorer operates is analogous to the workings of this factory. Think of IRIS Explorer itself as the factory. The Map Editor corresponds to the factory floor, and the modules to the machines. The raw materials are the data, fed in at one end and passing through the system into the visualization unit, the inspection area. Here, the finished product, which is the visual object or image, is inspected and, if necessary, tweaked. A little more color here, a slightly smoother isosurface there, and the object is ready for its destiny - to be interpreted.

Alongside the Map Editor is the Module Librarian, where the modules are stored. These correspond to functioning machines, a variety of which are brought out of storage and reconnected each time a new design is implemented on the factory floor. So specific modules are launched in the Map Editor and wired together into a map.

Raw materials are critical to the manufacturing process. The IRIS Explorer factory uses data as the manufacturing unit. It makes some of its own raw materials, in the form of generated lattices. But many designs will require materials from elsewhere, external data that needs to be picked over and cleaned up, sorted through and carefully sieved, before the machines will accept it. There are a number of reader modules for getting data in, plus a `flat file' format for the main datatypes - and of course the user can produce data reader modules using the module builder.

With data coming in and modules firing, the IRIS Explorer factory produces many interesting and informative geometric objects. However, the day may come when no modules are available in the Module Librarian to fulfill a part of the map design. This calls for a trip to the machine shop, the Module Builder. Here, you can build a module that will do exactly what you want it to do when it is wired into the map. It looks just like the other modules, with the same type of control panel and controls, and it can be stored and used again. Thus the scope of the factory has been enlarged.

However, large factory floors have a disadvantage. They can be noisy and messy, with lots of wires snaking here and looping there, and they tend to be crowded, on the principle that an empty space is immoral. Some machines may be running at less than their full capacity if a couple of their features are not needed for a particular design. Likewise with the IRIS Explorer Map Editor. When you create large maps, you might be tempted to think less of visualization systems and more of a bowl of noodle soup.

The IRIS Explorer factory has a way to cope with this. The manager scopes out a group of machines that for some reason are logically related, probably because they carry out closely related tasks, and selects certain of their functions to wire into a new control panel. The machines themselves are relegated, still intact, to the basement and the connecting wires come through the factory floor to the administrative, or group, control panel. In one easy move, the factory floor has gained a large open space, the assembly line has increased in efficiency, and the individual machines in the group are unscathed - simply out of sight until fetched up from the basement again. If you plan carefully, you could end up with one sleek control panel on the visualization unit and a completely clean and quiet floor.

The analogy should be clear. You can encapsulate a collection of modules in a group and gain all the benefits of a streamlined work area without sacrificing the integrity of the individual modules.

IRIS Explorer is a powerful and versatile system. The analogy of the factory necessarily simplifies its structure, but the examples in Chapter 1 give you a sense of what can be accomplished.

To use IRIS Explorer effectively, you should know what data you have, but you need no blueprint for what kind of visualization you want to produce. The great strength of IRIS Explorer is that you can innovate without retooling, and the design of your map reveals itself as you go. As with any exploration, you could end up with a map that takes you into uncharted realms of discovery and shows you implications of your data that you would not have thought existed.

The inventors of today have a distinct advantage over their predecessors. An ordinary factory floor is limited by the constraints of matter: the IRIS Explorer factory floor is limited only by the power of your imagination.


How to Use This Guide

The IRIS Explorer User's Guide describes how to use IRIS Explorer, which is a system for creating custom visualization programs and applications.

This guide is written for computational scientists and engineers in the fields of fluid dynamics, chemistry, meteorology, cosmology, physics, and mathematics. It addresses high-level users who are experts in their fields but are not programmers, and who will use the visual interface and tools in IRIS Explorer to create their models.

The guide assumes you have a basic understanding of your operating and windowing system.


Contents of This Guide

The IRIS Explorer User's Guide has seven chapters and two appendices. They cover the following topics:

Some of the examples are complete, and some are fragmentary. Maps for all the examples are included with the IRIS Explorer software.

This guide has two companion volumes:

IRIS Explorer Module Writer's Guide, which provides information on how to build your own modules with the Module Builder.

IRIS Explorer Reference Pages , which lists all the modules available with IRIS Explorer and provides information on the Application Programming Interface (API) routines.


Last modified: Thu Feb 13 12:49:54 1997
[ Documentation Home ]
© NAG Ltd. Oxford, UK, 1996