Your First Unity Game: A Complete 2D Game from A to Z

ASCENO / UNITY STUDY NOTES · 70

Your First Unity Game: A Complete 2D Game from A to Z

Làm game Unity đầu tiên: game 2D hoàn chỉnh từ A-Z

The lesson starts with a direct Unity screenshot so the practical action is visible. The nine following figures are language-neutral illustrations; the bilingual text below them carries the explanation. The main topic is unity tutorial game 2d. Figure 1 is practical evidence; figures 2–10 use only shapes, symbols, and visual relationships so they can remain unchanged across languages.

Learning goals

• Explain the concept with a model or data flow.
• Know exactly which Unity window to open.
• Predict the result before pressing Play and find evidence.
• Rebuild a small experiment and debug it methodically.

1. Hands-on practice in Unity

Open the test Scene, select the relevant object, and perform the action described in the lesson. This is a native Unity screenshot that shows where to begin; the steps and meaning are explained in the text below.

2. System illustration

A complete 2D game connects the pieces: Scenes, sprites, input, movement, collisions, UI, audio, score, restart, and a build. The scope is small, but the play loop should be complete. The illustration below contains no language-specific text; read it together with this explanation and the concrete steps.

• unity tutorial game 2d | the lesson concept | read the focus and hands-on example | do not infer it from object colours
• Input/setting | the input data or configuration | record the value before changing it | do not change several things at once
• Result/evidence | what must be observed in the Scene, Game, Inspector, or Console | capture the correct panel | a polished image is not evidence

3. Cause → result illustration

Read the arrow direction, relative position, and symbol changes as a causal relationship. The explanation below names each step in text rather than relying on words inside the image.

1. Scene
2. Sprite
3. Input
4. Movement
5. Collision
6. UI / Build

4. Sequence illustration

Open Unity and build a minimal 2D Scene: Player, Ground, Obstacle, and Goal. Run each milestone in the Game view; add UI, audio, and build only after movement and collision have evidence in the Console.

5. Object structure illustration

Read the object name in the Hierarchy first. If the name does not communicate its role, rename it in the test Scene; a screenshot is useful only when the reader knows what is selected.

6. Configuration illustration

Select the object representing unity tutorial game 2d in the Hierarchy. Read Transform first, then find the relevant Component/field. Record the current value before changing it; Lock the core loop first: start, control, challenge, fail, and replay

7. Result observation illustration

The Console is not decoration: use it to verify Build early after each milestone to catch platform issues. If no log appears, check the active object, script compilation, and Console filters before adding more code.

8. Code → state illustration

Do not copy code away from the Scene. Before each line, identify the input object/reference; after each line, identify the state or output that should change.

// PlayerController2D.cs
using UnityEngine;

public class PlayerController2D : MonoBehaviour
{
    [SerializeField] private Rigidbody2D body;
    [SerializeField] private float moveSpeed = 5f;
    [SerializeField] private float jumpVelocity = 8f;
    [SerializeField] private Transform groundCheck;
    [SerializeField] private LayerMask groundLayer;
    private float horizontal;

    private void Update()
    {
        horizontal = Input.GetAxisRaw("Horizontal");
        if (Input.GetButtonDown("Jump") && IsGrounded())
            body.linearVelocity = new Vector2(body.linearVelocity.x, jumpVelocity);
    }

    private void FixedUpdate()
    {
        body.linearVelocity = new Vector2(horizontal * moveSpeed, body.linearVelocity.y);
    }

    private bool IsGrounded() => Physics2D.OverlapCircle(groundCheck.position, .12f, groundLayer);
}

// Obstacle.cs
using UnityEngine;

public class Obstacle : MonoBehaviour
{
    [SerializeField] private float speed = 3f;

    private void Update()
    {
        transform.Translate(Vector3.left * speed * Time.deltaTime);
        if (transform.position.x < -14f) Destroy(gameObject);
    }

    private void OnTriggerEnter2D(Collider2D other)
    {
        if (other.CompareTag("Player"))
            FindFirstObjectByType<GameManager2D>().GameOver();
    }
}

// GameManager2D.cs
using UnityEngine;
using UnityEngine.SceneManagement;
using TMPro;

public class GameManager2D : MonoBehaviour
{
    [SerializeField] private GameObject gameOverPanel;
    [SerializeField] private TMP_Text scoreLabel;
    private float score;

    private void Update()
    {
        score += Time.deltaTime;
        scoreLabel.SetText("Score: {0:0}", score);
    }

    public void GameOver()
    {
        Time.timeScale = 0f;
        gameOverPanel.SetActive(true);
    }

    public void Restart()
    {
        Time.timeScale = 1f;
        SceneManager.LoadScene(SceneManager.GetActiveScene().buildIndex);
    }
}

9. Experiment illustration

This pillar project moves from a one-level obstacle-dodging idea through prototype, polish, and build. Each milestone has a completion check so beginners do not get lost in feature lists.

1. Lock the core loop first: start, control, challenge, fail, and replay.
2. Graybox with simple shapes before replacing them with art and audio.
3. Build early after each milestone to catch platform issues.
4. Run again after reverting to check that the result is reproducible.
5. Record the input value, action, result, and reason for the change.

10. Failure → fix illustration

• Selecting the wrong object or asset means a correct edit appears to do nothing.
• Changing several fields at once hides the cause.
• Looking only at the Scene while ignoring the Inspector/Console.
• Skipping verification specific to unity tutorial game 2d.

The ASCENO perspective: A good figure must help the reader answer one concrete question. If it does not show what to select, where to look, what to change, or where the result appears, it is not ready for documentation.