Book Image

SFML Game Development

By : Artur Moreira, Henrik Vogelius Hansson, Jan Haller, Henrik Valter Vogelius, SFML
Book Image

SFML Game Development

By: Artur Moreira, Henrik Vogelius Hansson, Jan Haller, Henrik Valter Vogelius, SFML

Overview of this book

Game development comprises the combination of many different aspects such as game logics, graphics, audio, user input, physics and much more. SFML is an Open Source C++ library designed to make game development more accessible, exposing multimedia components to the user through a simple, yet powerful interface. If you are a C++ programmer with a stack of ideas in your head and seeking a platform for implementation, your search ends here.Starting with nothing more than a blank screen, SFML Game Development will provide you with all the guidance you need to create your first fully featured 2D game using SFML 2.0. By the end, you'll have learned the basic principles of game development, including advanced topics such as how to network your game, how to utilize particle systems and much more.SFML Game Development starts with an overview of windows, graphics, and user inputs. After this brief introduction, you will start to get to grips with SFML by building up a world of different game objects, and implementing more and more gameplay features. Eventually, you'll be handling advanced visual effects, audio effects and network programming like an old pro. New concepts are discussed, while the code steadily develops.SFML Game Development will get you started with animations, particle effects and shaders. As well as these fundamental game aspects, we're also covering network programming to the extent where you'll be able to support the game running from two different machines. The most important part, the gameplay implementation with enemies and missiles, will make up the core of our top-scrolling airplane shoot' em-up game!You will learn everything you need in SFML Game Development in order to start with game development and come closer to creating your own game.
Table of Contents (18 chapters)
SFML Game Development
Credits
Foreword
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Updating the scene


In each frame, we update our world with all the entities inside. During an update, the whole game logic is computed: entities move and interact with each other, collisions are checked, and missiles are launched. Updating changes the state of our world and makes it progress over time, while rendering can be imagined as a snapshot of a part of the world at a given time point.

We can reuse our scene graph to reach all entities with our world updates. To achieve this, we implement a public update() member function in the SceneNode class. Analogous to the way we have proceeded for the draw() function, we split up update() into two parts: an update for the current node, and one for the child nodes. We thus write two private methods updateCurrent() and updateChildren(), of which the former is virtual.

All update functions take the frame time dt as a parameter of type sf::Time (the SFML class for time spans). This is the frame time we computed for the Game class in Chapter 1, Making...