QCad User Reference Manual

# 2 Preface

## Scope of This Manual

This manual is designed to get you started using QCad and to help you using it more efficiently. Further it will give you an idea of the more advanced possibilities behind QCad. Chapter 3 will introduce you in the world of computer aided design (CAD). If you've already worked with a CAD program before, you might want to skip this chapter.

## CAD - For the Uninitiated

If you take a look around you, most objects you will see once started off as a drawing in a CAD program. From your ball pen, your desk, furniture to your house and probably even your city - everything once had to be constructed either manually on paper or more likely with a CAD system.

CAD stands for Computer-Aided Design. It's essential to realize that CAD applications differ from painting or drawing programs. Drawings made in CAD applications represent real-world objects in their exact original measures. The most important factors are accuracy and to show as many details as necessary to produce the object. If you're used to drawing programs, you will most likely find it inconvenient that there's usually no or only limited drag-and-drop functionality in CAD systems. This is part of the idea, that everything is done accurately. The drawing doesn't only have to look accurate on the screen - it has to be accurate as a model. Moving an entity around means moving it from an exactly defined location to another exactly defined position. However, once you got used to this approach, you will never want to do technical drawings in an ordinary drawing program anymore.

## Is QCad for me?

There are many different CAD systems out there and depending on what you intend to do, QCad might or might not fit your bill. If you are looking for a 3D modeling CAD application, you'll have to look somewhere else. QCad is a 2D CAD program. That means that everything is projected onto a plane. This doesn't mean that it's only suitable to represent 2D objects though. A couple of 2D drawings which represent an object from different perspectives (e.g. from the side, the top and from the front) provide usually enough information to fully define the object and all its dimensions.

Some of the main reasons why you might want to use QCad are its simplicity, the user friendly interface, its many features or simply the fact that it works on your favorite platform - be it Linux, an other Unix system, Windows or Mac OS X. Last but not least QCad is part of the open source movement. This means that if you're a programmer you can add your own functionality.

QCad has an estimated user base of over 100'000 people worldwide. Its users range from industrial companies in the fields of mechanical and electronic engineering to private users, teachers and students. There are many other capable CAD systems out there and most of them offer much more than QCad does. But most of them are bound to one single platform or are simply not affordable for many potential users. That's where QCad kicks in. QCad targets the hobbyists, occasional CAD users and people who are not CAD professionals but still need to draw plans once in a while. QCad is the CAD for the rest of us.

## Who Is Behind QCad?

QCad is a product of RibbonSoft, a software engineering company based in Switzerland. However, many other people have contributed to QCad and it wouldn't be what it is today without the help of translators, developers and the feedback of QCad users. Please refer also to the company homepage of RibbonSoft for more information: www.ribbonsoft.com .

## How can I get QCad?

You can get the latest version of QCad from www.qcad.org . On this web site you can also find more documentation and other resources for QCad.

## QCad and Qt

Qt is the cross platform C++ application framework that QCad is based on. Much of the work involved in QCad is done by Trolltech ( www.trolltech.com ), the guys who develop Qt.