Unity Game Development Cookbook

Chapter 10. Behavior and AI

The appearance of intelligent, decision-based behavior is a core facet of building an engaging . Video game artificial intelligence (AI) isn’t like the rest of the AI field. It’s mostly fakery, tricks, and illusions of complexity. You don’t need to be an AI or machine learning wizard to build complex, engaging behaviors into video games. In this chapter, we’ll explore solutions to some of the most common problems game developers encounter when giving entities behavior and AI.

Tip

You can use Unity to work with genuine AI and machine learning! It’s outside the scope of this book, and not needed to create most sophisticated behaviors, but learn more about it at Unity’s Machine Learning Agents project on GitHub and on the Unity Machine Learning site.

10.1 Defining a Path That AI Entities and the Player Can Follow

Problem

You want to allow entities in your game to find paths around a scene.

Solution

Navigation meshes are easiest to set up when your level is made of objects that you don’t expect to move during gameplay, such as the ground, walls, and other obstacles:

1. Select the objects that you don’t expect to move.

2. At the top right of the Inspector, click the drop-down arrow and choose Navigation Static (Figure 10-1).

Figure 10-1. Setting a game object to be Navigation Static, through the Static menu

With at least one object marked as Navigation ...