Particle lifetime and speed in Unity - Mini Project: Build & Apply

Particle lifetime and speed

📖 Scenario: You are creating a simple particle effect in Unity. Each particle has a lifetime and a speed. You want to control these properties using code.

🎯 Goal: Build a Unity script that sets up particles with specific lifetimes and speeds, then prints their properties.

📋 What You'll Learn

Create a list of particles with given lifetimes and speeds

Add a speed threshold variable

Filter particles that have speed greater than the threshold

Print the filtered particles' lifetimes and speeds

💡 Why This Matters

🌍 Real World

Controlling particle effects in games or simulations to create visual effects like fire, smoke, or magic.

💼 Career

Understanding how to manage particle properties programmatically is useful for game developers and graphics programmers.

1

Create the initial particle list

Create a list called particles that contains these exact particle data as tuples: (2.5f, 5f), (3f, 7f), (1.5f, 4f), (4f, 6f). Each tuple represents (lifetime, speed).

Unity

# Create a list called particles with tuples (lifetime, speed)
# Your code here

Need a hint?

Use List<(float, float)> and initialize with the exact tuples.

2

Add a speed threshold variable

Add a float variable called speedThreshold and set it to 5.5f inside the Start() method, below the particles list.

Unity

using System.Collections.Generic;
using UnityEngine;

public class ParticleManager : MonoBehaviour
{
    void Start()
    {
        List particles = new List
        {
            (2.5f, 5f),
            (3f, 7f),
            (1.5f, 4f),
            (4f, 6f)
        };
        // Add speedThreshold variable here
        # Your code here
    }
}

Need a hint?

Declare float speedThreshold = 5.5f; inside Start().

3

Filter particles by speed

Create a new list called fastParticles that contains only the particles from particles where the speed is greater than speedThreshold. Use a foreach loop with variables lifetime and speed to iterate over particles.

Unity

using System.Collections.Generic;
using UnityEngine;

public class ParticleManager : MonoBehaviour
{
    void Start()
    {
        List particles = new List
        {
            (2.5f, 5f),
            (3f, 7f),
            (1.5f, 4f),
            (4f, 6f)
        };
        float speedThreshold = 5.5f;
        // Create fastParticles list and add particles with speed > speedThreshold
        # Your code here
    }
}

Need a hint?

Use a foreach loop with var (lifetime, speed) and an if to filter.

4

Print filtered particles

Use a foreach loop with variables lifetime and speed to iterate over fastParticles and print each particle's lifetime and speed in this exact format: "Particle - Lifetime: {lifetime}, Speed: {speed}" using Debug.Log.

Unity

using System.Collections.Generic;
using UnityEngine;

public class ParticleManager : MonoBehaviour
{
    void Start()
    {
        List particles = new List
        {
            (2.5f, 5f),
            (3f, 7f),
            (1.5f, 4f),
            (4f, 6f)
        };
        float speedThreshold = 5.5f;
        List fastParticles = new List();
        foreach (var (lifetime, speed) in particles)
        {
            if (speed > speedThreshold)
            {
                fastParticles.Add((lifetime, speed));
            }
        }
        // Print each particle in fastParticles
        # Your code here
    }
}

Need a hint?

Use Debug.Log($"Particle - Lifetime: {lifetime}, Speed: {speed}") inside a foreach loop over fastParticles.