🏁 Lesson 7.3: Win & Lose Conditions

A game needs a finish line. We'll make collecting every star a win, add a countdown timer for a lose, and show a result panel — turning our sandbox into an actual game with stakes.

🎯 Learning Objectives

Track total stars and detect when all are collected (win)
Add a countdown timer and detect time-out (lose)
Show a win/lose panel and pause the game
Use Time.timeScale to freeze gameplay

Estimated Time: 40 minutes

In This Lesson

The Result Screen

When the player collects the last star, we freeze the game and show a win message like this:

A real Unity render of the arena with a 'You Win!' panel overlaid. — Figure 1: The win panel over a real render. A lose screen works the same way when the timer hits zero.

Detecting a Win

The GameManager needs to know how many stars exist, then compare the score to that total. Add a totalStars and check it in AddPoint():

public int totalStars = 6;      // set to how many you placed

public void AddPoint()
{
    score++;
    UpdateScoreText();

    if (score >= totalStars)
    {
        Win();
    }
}

✅ Pro Tip: count automatically

Instead of typing 6 by hand, count them at start: totalStars = GameObject.FindGameObjectsWithTag("Star").Length; (tag your collectibles "Star" first). Now adding or removing stars just works.

A Countdown Timer (Lose)

A ticking clock adds tension. Count down in Update(); if it reaches zero before the win, the player loses:

public float timeLimit = 30f;    // seconds
public TMP_Text timerText;
private float timeLeft;
private bool gameOver = false;

void Start()
{
    timeLeft = timeLimit;
    UpdateScoreText();
}

void Update()
{
    if (gameOver) return;

    timeLeft -= Time.deltaTime;         // count down in real seconds
    timerText.text = "Time: " + Mathf.CeilToInt(timeLeft);

    if (timeLeft <= 0f)
    {
        Lose();
    }
}

💡 Mathf.CeilToInt rounds the decimal time up to a whole number, so the timer shows "5, 4, 3…" instead of "4.87, 4.86…".

Showing the Panel & Freezing the Game

Both endings show a message and stop the action. Freezing everything is a one-liner: set Time.timeScale = 0, which pauses all time-based movement and physics.

public TMP_Text resultText;    // a big centred text, hidden at start

void Win()
{
    gameOver = true;
    resultText.text = "🎉 You Win!";
    resultText.gameObject.SetActive(true);
    Time.timeScale = 0f;       // freeze the game
}

void Lose()
{
    gameOver = true;
    resultText.text = "⏱ Time's Up!";
    resultText.gameObject.SetActive(true);
    Time.timeScale = 0f;
}

⚠️ Remember to reset timeScale

Time.timeScale = 0 stays 0 even into a new game. If you add a "Play Again" button that reloads the scene, set Time.timeScale = 1f first, or the new game will start frozen.

graph TD A[Collect a star] --> B{score >= total?} B -->|yes| W[Win: show panel, freeze] C[Timer each frame] --> D{time <= 0?} D -->|yes| Lo[Lose: show panel, freeze]

Hands-on Exercise

🏋️ Exercise: Add a finish line

Add totalStars, a timer, and a hidden centred resultText to the GameManager (wire the text slots).
Make collecting the last star trigger Win.
Make the timer hitting zero trigger Lose.
Play twice: once collecting all stars in time (win), once letting the clock run out (lose).

💡 The win never triggers

Check totalStars matches the number of stars actually in the scene (or auto-count them). If you added extra stars, the count is off.

💡 The game starts frozen after replaying

You left Time.timeScale at 0. Set it back to 1f when starting or reloading.

🎯 Quick Quiz

Question 1: What does Time.timeScale = 0f do?

Question 2: Why subtract Time.deltaTime from the timer each frame?

Summary

🎉 Key Takeaways

Win when score >= totalStars; auto-count stars by tag for safety.
Lose when a Time.deltaTime countdown reaches zero.
Show a result text and freeze with Time.timeScale = 0f.
Reset timeScale to 1 when replaying, or the next game starts frozen.

🚀 What's Next?

It's a real game now — win, lose, and all. The final touch is juice: particles, glow, and sound. Lesson 7.4 adds the polish.