Book Image

Game Programming Using Qt: Beginner's Guide

By : Lorenz Haas, Witold Wysota, Witold Wysota, Lorenz Haas
Book Image

Game Programming Using Qt: Beginner's Guide

By: Lorenz Haas, Witold Wysota, Witold Wysota, Lorenz Haas

Overview of this book

Qt is the leading cross-platform toolkit for all significant desktop, mobile, and embedded platforms and is becoming more popular by the day, especially on mobile and embedded devices. Despite its simplicity, it's a powerful tool that perfectly fits game developers’ needs. Using Qt and Qt Quick, it is easy to build fun games or shiny user interfaces. You only need to create your game once and deploy it on all major platforms like iOS, Android, and WinRT without changing a single source file. The book begins with a brief introduction to creating an application and preparing a working environment for both desktop and mobile platforms. It then dives deeper into the basics of creating graphical interfaces and Qt core concepts of data processing and display before you try creating a game. As you progress through the chapters, you’ll learn to enrich your games by implementing network connectivity and employing scripting. We then delve into Qt Quick, OpenGL, and various other tools to add game logic, design animation, add game physics, and build astonishing UI for the games. Towards the final chapters, you’ll learn to exploit mobile device features such as accelerators and sensors to build engaging user experiences. If you are planning to learn about Qt and its associated toolsets to build apps and games, this book is a must have.
Table of Contents (18 chapters)
Game Programming Using Qt
About the Authors
About the Reviewers

Integrating Qt and Qt Script

So far, we were only evaluating some standalone scripts that could make use of the features built in JavaScript. Now, it is time to learn to use data from your programs in the scripts.

This is done by exposing different kinds of entities to and from scripts.

Exposing objects

The simplest way to expose data to Qt Script is to take advantage of Qt's meta-object system. Qt Script is able to inspect QObject instances and detect their properties and methods. To use them in scripts, the object has to be visible to the script execution context. The easiest way to make this happen is to add it to the engine's global object or to some context's activation object. As you remember, all data between the script engine and C++ is exchanged using the QScriptValue class, so first we have to obtain a script value handle for the C++ object:

QScriptEngine engine;
QPushButton *button = new QPushButton("Button");
// …
QScriptValue scriptButton = engine.newQObject(button);