Hey guys! Ever dreamed of making your own awesome platformer game? Well, you're in the right place! Unity is a fantastic game engine, and we're gonna walk through creating a basic platformer from scratch. Get ready to jump, run, and maybe even face some pixelated enemies!

Setting Up Your Unity Project

First things first, let's get a new Unity project up and running. Open up Unity Hub and click on "New Project." Choose a 2D template because, well, platformers are generally 2D. Give your project a cool name like "AwesomePlatformer" or whatever strikes your fancy. Choose a location to save it, and hit that "Create" button. Boom! You're officially a game developer (sort of).

Once Unity loads up, you'll see the main editor window. It might look a little intimidating at first, but don't worry, we'll break it down. The Scene view is where you visually arrange your game world. The Game view is what the player sees when they're playing. The Hierarchy window lists all the objects in your current scene. And the Inspector window lets you tweak the properties of selected objects.

Before we dive in, let's set up the scene a bit. Right-click in the Hierarchy window and create a new 2D -> Tilemap -> Rectangular. This creates a Grid object with a Tilemap as a child. Tilemaps are perfect for building the level's ground, walls, and other static elements. Rename the Tilemap object to something descriptive like "GroundTilemap". Next, let's import some assets. You can find tons of free tile sets online. A great place to find assets is the Unity Asset Store or websites like Kenney.nl. Download a tileset you like, and drag the image file into your Unity project's Assets folder. In the Inspector window for your tileset image, change the Texture Type to "Sprite (2D and UI)" and click "Apply." Then, open the Sprite Editor (button in the Inspector). Slice the tileset into individual tiles. Use the Automatic slicing option and adjust the Pixel Size if necessary to match your tiles. Click "Apply" again. Now, create a new Palette in the Tile Palette window (Window -> Tile Palette). This palette will hold all your tiles for easy access. Drag the sliced tiles from your Project window into the Tile Palette. Now you can select tiles from the palette and paint them onto your GroundTilemap in the Scene view. Create a basic ground for your player to stand on. Make it as long or short as you like for now. We can always adjust it later. And that’s it for setting up the Unity Project, now let us move on to other steps.

Creating the Player Character

Okay, time to create our hero! Right-click in the Hierarchy window and create a new 2D -> Sprite -> Square. This will be our placeholder player. Rename it to "Player." In the Inspector window, change the Color property to something other than white so you can see it easily. Add a Rigidbody 2D component to the Player (Add Component -> Physics 2D -> Rigidbody 2D). This will allow the player to be affected by gravity and other forces. Set the Body Type to "Kinematic" for now. We'll control the movement directly with code, so we don't want the physics engine messing with us too much. Add a Box Collider 2D component to the Player (Add Component -> Physics 2D -> Box Collider 2D). This will define the player's collision area. Adjust the Size property of the Box Collider 2D so it fits snugly around the player sprite. Now, let's write some code to make our player move. Create a new C# script in your Project window (Create -> C# Script) and name it "PlayerMovement". Double-click the script to open it in your code editor (like Visual Studio).

Here's a basic PlayerMovement script to get you started:

using UnityEngine;

public class PlayerMovement : MonoBehaviour
{
    public float moveSpeed = 5f;
    public float jumpForce = 10f;
    public Transform groundCheck;
    public float groundCheckRadius = 0.2f;
    public LayerMask groundLayer;

    private Rigidbody2D rb;
    private bool isGrounded;

    void Start()
    {
        rb = GetComponent<Rigidbody2D>();
    }

    void Update()
    {
        // Horizontal movement
        float horizontalInput = Input.GetAxisRaw("Horizontal");
        rb.velocity = new Vector2(horizontalInput * moveSpeed, rb.velocity.y);

        // Jumping
        isGrounded = Physics2D.OverlapCircle(groundCheck.position, groundCheckRadius, groundLayer);
        if (Input.GetButtonDown("Jump") && isGrounded)
        {
            rb.velocity = new Vector2(rb.velocity.x, jumpForce);
        }
    }
}

Save the script and go back to Unity. Attach the PlayerMovement script to the Player object by dragging it from the Project window onto the Player in the Hierarchy window. In the Inspector window for the Player, you'll see the public variables we declared in the script: moveSpeed, jumpForce, groundCheck, groundCheckRadius, and groundLayer. Create an empty child object under the Player and name it "GroundCheck". This will be used to determine if the player is touching the ground. Position the GroundCheck object at the player's feet. Drag the GroundCheck object from the Hierarchy window into the groundCheck field in the PlayerMovement component in the Inspector. Create a new Layer in the Layers dropdown (Edit -> Project Settings -> Tags and Layers). Name it "Ground". Select your GroundTilemap in the Hierarchy window and set its Layer to "Ground". Back in the Inspector for the Player, set the groundLayer field in the PlayerMovement component to the "Ground" layer you just created. Adjust the moveSpeed and jumpForce values to your liking. Try playing the game now. You should be able to move left and right with the A/D or left/right arrow keys, and jump with the spacebar. If the player falls through the ground, make sure the GroundTilemap's Layer is set to "Ground" and that the groundLayer field in the PlayerMovement script is also set to "Ground".

Designing the Game Level

Alright, let’s get creative and design a cool level for our game! Using the Tile Palette, paint more ground tiles to create platforms, walls, and other obstacles. Experiment with different tile arrangements to make the level interesting and challenging. Consider adding gaps that the player has to jump over, or narrow platforms that require precise movement. Think about where you want to place enemies, power-ups, and the level's exit.

To add some depth and visual interest, you can create multiple Tilemaps. For example, you could have a "BackgroundTilemap" behind the "GroundTilemap" to display scenery like mountains, trees, or clouds. Remember to adjust the Z position of each Tilemap in the Inspector window so that they are rendered in the correct order. You can also add decorative elements like sprites or particle effects to make the level more visually appealing. For example, you could add some animated torches or falling leaves to create a more immersive atmosphere. Don't be afraid to experiment and try new things. The most important thing is to have fun and create a level that you enjoy playing.

Once you have a basic level layout, you can start thinking about adding more advanced features like moving platforms, traps, and secrets. You could create a moving platform by attaching a script to a tile or sprite that moves it back and forth between two points. You could create a trap by placing a trigger collider that activates a damaging effect when the player enters it. You could create a secret by hiding a collectible item in a hard-to-reach location. The possibilities are endless!

Adding Enemies

No platformer is complete without some enemies! Let's add a simple enemy that moves back and forth and damages the player on contact. Create a new 2D -> Sprite -> Square in the Hierarchy window and rename it "Enemy". Change its color to something menacing like red or purple. Add a Rigidbody 2D component to the Enemy and set its Body Type to "Kinematic". Add a Box Collider 2D component to the Enemy and adjust its size to fit the sprite. Create a new C# script named "EnemyMovement" and attach it to the Enemy object.

Here's a simple EnemyMovement script:

using UnityEngine;

public class EnemyMovement : MonoBehaviour
{
    public float moveSpeed = 2f;
    public float moveDistance = 3f;
    public bool moveRight = true;

    private Vector3 startPosition;

    void Start()
    {
        startPosition = transform.position;
    }

    void Update()
    {
        if (moveRight)
        {
            transform.position += Vector3.right * moveSpeed * Time.deltaTime;
            if (transform.position.x > startPosition.x + moveDistance)
            {
                moveRight = false;
            }
        }
        else
        {
            transform.position -= Vector3.right * moveSpeed * Time.deltaTime;
            if (transform.position.x < startPosition.x - moveDistance)
            {
                moveRight = true;
            }
        }
    }
}

Back in Unity, adjust the moveSpeed and moveDistance values in the Inspector window to control how fast and far the enemy moves. Now, let's add some code to the PlayerMovement script to handle collisions with the enemy. Add a OnTriggerEnter2D function to the PlayerMovement script:

    void OnTriggerEnter2D(Collider2D collision)
    {
        if (collision.gameObject.CompareTag("Enemy"))
        {
            // Handle player damage here
            Debug.Log("Player hit by enemy!");
        }
    }

In Unity, select the Enemy object and add a Tag to it (Add Tag in the Inspector, then create a new tag named "Enemy"). Set the Enemy's Tag to "Enemy". Now, when the player collides with the enemy, the OnTriggerEnter2D function will be called, and you'll see "Player hit by enemy!" in the console. You can replace the Debug.Log with code to reduce the player's health, play a sound effect, or trigger other events. Remember to set Is Trigger to true in the box collider.

You can create different types of enemies with varying behaviors by creating new scripts and attaching them to different enemy prefabs. For example, you could create an enemy that shoots projectiles, an enemy that jumps, or an enemy that patrols a specific area. You can also adjust the enemy's health, damage, and other stats to make them more or less challenging to defeat. Remember to balance the difficulty of the enemies with the overall difficulty of the level to create a fun and engaging experience for the player.

Collecting Items

Let's add some collectible items to our game! This will give the player an extra objective and make the game more rewarding. Create a new 2D -> Sprite -> Circle in the Hierarchy window and rename it "Coin". Change its color to something shiny like yellow or gold. Add a Circle Collider 2D component to the Coin and set Is Trigger to true. Create a new C# script named "CoinCollection" and attach it to the Coin object.

Here's a simple CoinCollection script:

using UnityEngine;

public class CoinCollection : MonoBehaviour
{
    void OnTriggerEnter2D(Collider2D collision)
    {
        if (collision.gameObject.CompareTag("Player"))
        {
            // Handle coin collection here
            Debug.Log("Coin collected!");
            Destroy(gameObject);
        }
    }
}

In Unity, select the Player object and add a Tag to it if you haven't already. Set the Player's Tag to "Player". Now, when the player collides with the coin, the OnTriggerEnter2D function will be called, and you'll see "Coin collected!" in the console, and the coin will be destroyed. You can replace the Debug.Log with code to increase the player's score, play a sound effect, or trigger other events.

You can create different types of collectible items with varying effects by creating new scripts and attaching them to different item prefabs. For example, you could create a power-up that increases the player's speed, a health potion that restores the player's health, or a key that unlocks a door. You can also adjust the item's value, rarity, and other stats to make them more or less desirable to collect. Remember to place the items strategically throughout the level to encourage exploration and reward the player for taking risks.

What's Next?

This is just the beginning! You've got the basic framework for a platformer game. From here, you can add all sorts of cool features: more enemy types, power-ups, traps, a scoring system, sound effects, music, and of course, more levels! Keep experimenting, keep learning, and most importantly, keep having fun! You're on your way to becoming a platformer game dev master!