Master Unity 3D AI with Rain Indie: Creating Ghost Patrol

Table of Contents:

1. Introduction
2. Tutorial Number One Recap
3. Creating a Waypoint Route
4. Adding Waypoints to the Route
5. Configuring the Ghost Monster
6. Creating the Ghost AI
7. Understanding Behavior Trees
8. Configuring the Ghost Behavior Tree
9. Using the Waypoint Patrol Action
10. Setting the Move Target Variable
11. Conclusion

🎯 Introduction

In this tutorial, we will be exploring how to use Unity 3D's AI system, specifically focusing on Rain Indie from Rival Theories. This tutorial is the Second part of a series, where we will be creating a PowerPoint slideshow using the Unity 3D AI system. If you haven't watched the first tutorial, I highly recommend going back and watching it to get familiar with the project we will be building upon. In the previous tutorial, we created a character, a main camera with directional light, and a ground plane. We also learned how to create a Waypoint Route using Rain. In this tutorial, we will be adding waypoints to the route and configuring the AI for our ghost monster.

🔁 Tutorial Number One Recap

Before we proceed, let's do a quick recap of what we covered in tutorial number one. In the first tutorial, we created the foundation of our project. We set up our character, main camera, directional light, and ground plane. Additionally, we created a Waypoint Route using Rain, which serves as a path for our ghost monster to patrol. If you missed any of these steps, I highly recommend watching tutorial number one to get up to speed.

🛣️ Creating a Waypoint Route

Now that we have a basic understanding of what we covered in the previous tutorial, let's dive into creating our Waypoint Route. To create a Waypoint Route, you will need to click on the Rain tab at the top of the Unity editor. From the dropdown menu, select "Create Waypoint Route." By default, a new Waypoint Route will be generated and named "Waypoint Route One." To ensure Clarity, we can rename it to something more descriptive, such as "Route One."

➕ Adding Waypoints to the Route

Once we have our Waypoint Route set up, it's time to add waypoints to define the path for our ghost monster. To add a waypoint, select the Route One object in the Hierarchy window, then click on the "+ ADD" button in the Inspector panel. You can also use the shortcut 'W' key to add waypoints. Each waypoint represents a specific location that our ghost monster will move towards when patrolling. Feel free to experiment with the number and placement of waypoints to create diverse and interesting patrol paths.

⚙️ Configuring the Ghost Monster

Before we can proceed with configuring the AI for our ghost monster, let's make some adjustments to its initial position. Grab the ghost monster object and position it slightly offset from the first waypoint. This will ensure that our ghost starts its patrol from a specific direction. Additionally, let's assign the ghost monster an idle animation to give it some personality. You can choose from animations like idle hover, idle side-to-side, or any animation that suits your ghost monster's behavior.

🤖 Creating the Ghost AI

Now that we have our Waypoint Route and the ghost monster ready, it's time to create the AI for the ghost. To do this, select the ghost monster object in the Hierarchy and click on the "Create AI" button under the Rain tab. This will automatically generate the necessary AI components for our ghost. Don't worry, this process is incredibly simple and takes care of most of the AI setup for us.

🌳 Understanding Behavior Trees

To better understand how our ghost monster's AI will behave, we need to familiarize ourselves with Behavior Trees. Behavior Trees are a hierarchical system that defines the actions and decisions for an AI entity. It operates in a tree-like structure, where each node represents a specific action, decision, or condition. In our case, we will be creating a Behavior Tree for our ghost monster to define its patrol behavior.

📊 Configuring the Ghost Behavior Tree

Now, let's configure the Behavior Tree for our ghost. Open the Behavior Editor by clicking on the "Open Behavior Editor" button in the Rain tab. In the Behavior Editor, create a new Behavior Tree by clicking on the "Create New Behavior Tree" button. Name the Behavior Tree "Ghost" or choose a name that suits your project. By default, a sequencer node is created, but we will switch it to a Parallel node to allow simultaneous execution of multiple actions.

🚶 Using the Waypoint Patrol Action

To implement the waypoint patrol behavior, we will utilize the Waypoint Patrol action provided by Rain. Add a new action node under the parallel node and select Waypoint Patrol. Connect this action node to the parallel node using an edge. The Waypoint Patrol action allows us to specify the waypoint route we created earlier and configure its looping behavior. We want our ghost to patrol the waypoints continuously, so we'll select "Loop" as the looping option.

📍 Setting the Move Target Variable

In order for the Waypoint Patrol action to function correctly, we need to provide it with a Move Target variable. This variable stores information about the next waypoint the ghost should move towards. In the Waypoint Patrol action's inspector, locate the Move Target Variable field and assign it a variable name. We can call it "VAR_Path" to indicate that it contains information about the path our ghost will follow.

🎯 Conclusion

In this tutorial, we have learned how to create a Waypoint Route, add waypoints to define a patrol path, and configure the AI for our ghost monster. We have also explored Behavior Trees and configured the ghost's Behavior Tree to implement the waypoint patrol behavior using the Waypoint Patrol action. By following these steps, you now have a basic understanding of how to set up AI behavior using Rain Indie from Rival Theories. In the next tutorial, we will continue with the implementation and introduce a moving character.

🌟 Highlights

• Learn how to set up AI behavior using Unity 3D's AI system, Rain Indie from Rival Theories.
• Create a Waypoint Route to define a patrol path for your AI Character.
• Add waypoints to the route and configure their properties.
• Configure the AI for your character using Rain's AI system.
• Understand Behavior Trees and their role in defining AI behavior.
• Configure a Behavior Tree for your AI character to implement waypoint patrol.
• Utilize the Waypoint Patrol action to control the movement of your character between waypoints.

❓ FAQ

Q: Can I create a more complex patrol path with multiple waypoint routes? A: Absolutely! By adding multiple Waypoint Routes and linking them together, you can create more intricate patrol paths for your AI character.

Q: Can I customize the animations for my ghost monster? A: Yes, you can assign different animations to your ghost monster using Unity's animation system. This allows you to bring your AI character to life and add unique behaviors.

Q: Is Rain Indie from Rival Theories the only AI system available in Unity? A: No, Unity offers several AI solutions and plugins. Rain Indie from Rival Theories is just one of them. Feel free to explore other options and choose the one that best suits your project's requirements.

Q: Can I create a Behavior Tree with more complex behaviors besides waypoint patrol? A: Absolutely! Behavior Trees provide a flexible framework to implement a wide range of AI behaviors, including chasing, attacking, and decision-making. With Rain Indie, you can easily expand the capabilities of your AI character.

Q: Can I combine multiple AI behaviors in a single Behavior Tree? A: Yes, Behavior Trees allow you to combine multiple behaviors to create complex AI systems. Each behavior can be represented as a node in the Behavior Tree, allowing for dynamic and flexible AI behavior.

Q: Are there any online resources available for further learning about Unity AI systems? A: Yes, there are many online tutorials, documentation, and forums dedicated to Unity AI systems. Unity's official website, as well as various community-based resources, provide extensive learning material to help you dive deeper into AI development in Unity.

🌐 Resources

• Unity Official Website
• Rain Indie from Rival Theories Documentation
• YouTube Channel of Recommended Tutor