Book Image

Unity Artificial Intelligence Programming - Fifth Edition

By : Dr. Davide Aversa
Book Image

Unity Artificial Intelligence Programming - Fifth Edition

By: Dr. Davide Aversa

Overview of this book

Developing artificial intelligence (AI) for game characters in Unity has never been easier. Unity provides game and app developers with a variety of tools to implement AI, from basic techniques to cutting-edge machine learning-powered agents. Leveraging these tools via Unity's API or built-in features allows limitless possibilities when it comes to creating game worlds and characters. The updated fifth edition of Unity Artificial Intelligence Programming starts by breaking down AI into simple concepts. Using a variety of examples, the book then takes those concepts and walks you through actual implementations designed to highlight key concepts and features related to game AI in Unity. As you progress, you’ll learn how to implement a finite state machine (FSM) to determine how your AI behaves, apply probability and randomness to make games less predictable, and implement a basic sensory system. Later, you’ll understand how to set up a game map with a navigation mesh, incorporate movement through techniques such as A* pathfinding, and provide characters with decision-making abilities using behavior trees. By the end of this Unity book, you’ll have the skills you need to bring together all the concepts and practical lessons you’ve learned to build an impressive vehicle battle game.
Table of Contents (17 chapters)
1
Part 1:Basic AI
6
Part 2:Movement and Navigation
11
Part 3:Advanced AI

Avoiding obstacles

In this section, we explore obstacle avoidance. As a first step, we need, of course, obstacles. So, we set up a scene similar to the one shown in Figure 6.6. Then, we create a script for the main character to avoid obstacles while trying to reach the target point. The algorithm presented here uses the raycasting method, which is very straightforward. However, this means it can only avoid obstacles that are blocking its path directly in front of it:

Figure 6.6 – A sample scene setup

We make a few cube entities and group them under an empty game object called Obstacles to create the environment. We also create another cube object called Vehicle and give it the obstacle avoidance script. Finally, we create a plane object representing the ground.

Figure 6.7 – Here is the structure of the scene's Hierarchy

It is worth noting that the Vehicle object does not perform pathfinding, that is, the active search...