title>Unity Basics Course: Creating Function by State

Hello! In this tutorial, we will learn how to create state-based functions in Unity. Unity is an excellent game engine, but its usage can be somewhat difficult for beginners. This tutorial will specifically explain the concepts of basic state management and the process of creating state-based functions.

1. What is a State?

A state represents the current situation of an object, determining how various elements of the game behave and interact. For example, there are various states such as the character sitting, walking, or jumping. States are an important concept in defining events and actions in your game.

1.1 Importance of States

Through state management, we can define various behaviors and actions within the game. Since the actions a character can perform change based on the state, it significantly impacts the flow of the game and the user experience.

2. Creating State-Based Functions

Now, let’s learn how to create state-based functions in Unity. We will create a simple character controller for this purpose.

2.1 Creating a New Script

Create a new C# script in the Unity editor. Let’s name it CharacterController. Add the following code to the script:

using UnityEngine;

public class CharacterController : MonoBehaviour
{
    private enum State { Idle, Walking, Jumping }
    private State currentState = State.Idle;

    private void Update()
    {
        switch (currentState)
        {
            case State.Idle:
                HandleIdleState();
                break;
            case State.Walking:
                HandleWalkingState();
                break;
            case State.Jumping:
                HandleJumpingState();
                break;
        }
    }

    private void HandleIdleState()
    {
        // Idle state logic
        if (Input.GetKeyDown(KeyCode.W))
        {
            currentState = State.Walking;
        }
        else if (Input.GetKeyDown(KeyCode.Space))
        {
            currentState = State.Jumping;
        }
    }

    private void HandleWalkingState()
    {
        // Walking state logic
        if (Input.GetKeyDown(KeyCode.S))
        {
            currentState = State.Idle;
        }
        else if (Input.GetKeyDown(KeyCode.Space))
        {
            currentState = State.Jumping;
        }
        // Implement walking movement
    }

    private void HandleJumpingState()
    {
        // Jumping state logic
        // Set to return to idle state after jumping is done
        currentState = State.Idle;
    }
}

2.2 Explanation

In the above code, we define three states: Idle, Walking, and Jumping using an enum named State. The currentState variable manages the current state. The Update method calls appropriate functions (e.g., HandleIdleState, HandleWalkingState, HandleJumpingState) based on the current state.

2.3 State Transition

State transitions occur based on user input. In the idle state, you can press the W key to transition to the walking state, and the Space key to transition to the jumping state. In the walking state, you can press the S key to return to the idle state, and the Space key to transition to the jumping state. In the jumping state, it generally returns to the idle state after the jump is completed.

3. Advantages of State-Based Functions

There are several advantages to using state-based functions:

• Improved Code Readability: By separating the code based on states, the logic for each state is clearly defined.
• Ease of Maintenance: It becomes easier to add or modify functionality based on states.
• Scalability: Adding new states becomes straightforward, making it advantageous when expanding the game’s features.

4. Practice: Adding State-Based Functions

Now, try adding your own character states. For example, add a new state called “Running” and implement transitioning to that state when the user presses the Shift key.

private enum State { Idle, Walking, Jumping, Running }

// Add the following logic in the appropriate part of the code
if (Input.GetKeyDown(KeyCode.LeftShift))
{
    currentState = State.Running;
}

// Running logic
private void HandleRunningState()
{
    // Running logic
   
    if (Input.GetKeyDown(KeyCode.S))
    {
        currentState = State.Idle;
    }
    // ...
}

5. Conclusion

In this tutorial, we learned about creating state-based functions in Unity. State management is a crucial aspect of game development, and a well-designed state system increases code readability and ease of maintenance. Implement various states to enrich your own game!

Thank you. See you in the next tutorial!