Create Stunning 3D Terrain in Unity

Table of Contents

1. Introduction
2. Variables and Theories
3. Unity Job System and Burst Compiler
4. Implementing the Chunk Learning System
5. Structs for Mesh and Noise Variables
6. Height Map Generator
7. Native Arrays and Execute Function
8. Creating the Mesh
9. Disposing and Returning the Mesh
10. Using the Burst Compile Attribute
11. Final Steps: Generate Map Function
12. Setting Up in the Editor
13. Conclusion

Introduction

In this article, we will dive into the process of creating a procedural terrain chunk in Unity using C# code. We will start by defining the variables and theories involved in the terrain generation process. Then, we will explore the Unity job system and burst compiler, which allow us to optimize the performance of our code. Next, we will implement the chunk learning system to generate a height map at the beginning of the game. This will significantly improve rendering and procedural times. We will discuss the necessary structs for mesh and noise variables and how to generate a height map using the job system. Additionally, we will cover the creation of a mesh and the disposal of native arrays. Finally, we will explain how to use the burst compile attribute and provide a step-by-step guide for the final implementation of our terrain generation system. So, let's get started!

1. Variables and Theories

Before we delve into the code, let's define some important variables and theories that will be used in the terrain generation process. First, we need to determine the number of squares on the side of the chunk. This will be defined by the variable "grid detail." Additionally, we have the variables "width" and "height," which determine the size and height of the terrain, respectively. We also need to understand the concept of noise, which will be used to calculate the terrain's height values. As we progress through the code, we will provide more detailed explanations of these variables and theories.

2. Unity Job System and Burst Compiler

In traditional Unity C# code, scripts are executed sequentially on the main thread. However, modern CPUs often come with multiple threads that can be utilized to speed up calculations. We can make use of these additional threads using the Unity job system and burst compiler. By running parallel loops on separate worker threads, we can significantly improve performance. In our case, we will run loops to calculate the noise values for each vertex of the terrain. This approach will speed up the terrain generation process, providing substantial performance boosts.

3. Implementing the Chunk Learning System

To further enhance performance, we will implement the chunk learning system. This system involves generating a height map at the beginning of the game, storing it, and then reading and displaying the data at runtime. This approach eliminates the need for real-time calculations, resulting in faster rendering and procedural times. Although this may seem like extra work for the CPU initially, the long-term benefits in terms of performance outweigh the initial overhead. Implementing the chunk learning system will propel our render times to over 200 FPS and procedural times to over 800.

4. Structs for Mesh and Noise Variables

To organize our code and variables, we will create two structs: one for mesh variables and one for noise variables. These structs will hold the necessary variables for generating the mesh and applying noise to the terrain. We will explain these variables in more detail as we progress through the code.

5. Height Map Generator

Within the struct for noise variables, we will create a height map generator. This generator will utilize the job system to calculate the height values for each vertex of the terrain. We will use a native array to store the height map, color map, and gradient values required for coloring. In the execute function of the job, we will calculate the position of each vertex, generate a noise value, and assign it to the corresponding position on the height map. We will also normalize the height value and use the gradient array to color the vertex. By creating native arrays and a return and dispose function, we ensure efficient memory management and avoid memory leaks in our code.

6. Native Arrays and Execute Function

In the main C# script, we will create a function called "generate map" that initializes the necessary variables and arrays. We will also define a native array to hold the gradient values for coloring the terrain. Additionally, we will create variables for the mesh filter, mesh, noise variables, and gradient. Within the "generate map" function, we will loop through the gradient values, run the noise job, and schedule it to complete. We will also run the mesh job, assigning the vertex and triangle arrays to create the mesh. Finally, we will set the mesh of the mesh filter and dispose of the gradient array.

7. Creating the Mesh

To create the mesh, we will define a struct for the mesh variables. This struct will contain the necessary variables for generating the mesh, such as vertex and triangle arrays. In the execute function of the mesh job, we will calculate the positions of each square's vertices and assign the correct values to the vertex and triangle arrays. By creating a return and dispose function for the mesh struct, we ensure proper memory management.

8. Disposing and Returning the Mesh

After generating the mesh, we need to dispose of the native arrays to avoid memory leaks. We will create a dispose function within the mesh struct to handle this. Additionally, we will create a return function that returns the mesh variables, allowing us to use the generated mesh for rendering.

9. Using the Burst Compile Attribute

To further optimize our code, we will use the burst compile attribute atop both the mesh and noise generator structs. This attribute tells Unity to compile the structs using the burst compiler, which greatly improves performance. By selecting the appropriate burst attributes and ensuring the necessary packages are installed, we can maximize the efficiency of our terrain generation system.

10. Final Steps: Generate Map Function

To complete the implementation of our terrain generation system, we will finalize the generate map function. We can place this function in the start method or the on validate method, depending on our preferences. The generate map function generates the terrain, sets up necessary attributes, and ensures real-time updates in the Unity editor. By following the provided step-by-step guide, we can successfully generate a procedural terrain in Unity.

11. Setting Up in the Editor

To visualize the generated terrain, we need to set up the necessary components in the Unity editor. First, we create an empty game object with a mesh filter and renderer. We then attach the script to this game object. Additionally, we can create a Shader graph to display the color map by connecting a vertex color node to the base color.

12. Conclusion

In this article, we explored the process of creating a procedural terrain chunk in Unity using C# code. We discussed important variables and theories, such as the grid detail, width, and height. We learned about the Unity job system and burst compiler and how they can significantly improve performance. We explored the implementation of the chunk learning system and how it can boost rendering and procedural times. Within our code, we created structs for mesh and noise variables, implemented a height map generator using the job system, and created the mesh for rendering. We optimized our code using the burst compile attribute and provided a step-by-step guide for the final implementation. By following this guide, we can successfully generate procedural terrains in Unity and unleash our creativity in game development.