Particle Systems In Unity

A Particle System is a component that spawns and controls many small objects called particles. Each particle has its own position, velocity, color, size and lifetime.

Creating a Particle System

Right-click in Hierarchy -> Effects -> Particle System.
A small cloud of white dots appears in Scene view.
Press Play to see particles moving.

Creating-Particle-System-In-Unity — Creating Particle System In Unity

Particle System Inspector

Select the Particle System GameObject. The Inspector has many modules (collapsible sections):

Main: Controls duration, looping, start speed, start size, and max particles.
Emission: Controls how many particles spawn per second.
Shape: Defines the spawn area shape (cone, sphere, box, etc.).
Color over Lifetime: Controls how particle color changes as it ages.
Size over Lifetime: Controls how particle size changes over time.
Renderer: Determines which material or texture the particle uses.

Particle-System-Inspector-In-Unity — Particle System Inspector In Unity

Example 1: Dust Particles (Simple)

Create a simple dust effect for a character landing.

Step 1: Create Particle System (Hierarchy - Effects - Particle System).

Step 2: In Main module:

Duration = 0.5 (plays for half second).
Looping = Unchecked (plays once).
Start Speed = 2.
Start Size = 0.3.
Max Particles = 20.

Step 3: In Emission module:

Rate over Time = 0 (disable).
Click "+" to add a Burst.
Burst Time = 0.
Count = 20.

Step 4: In Shape module:

Shape = Hemisphere.
Radius = 0.5.

Step 5: In Color over Lifetime module:

Check the box.
Click gradient bar.
Set color from brown to transparent.

Dust-Particles-In-Unity — Dust Particle In Unity

Playing Particle from Script

To play the dust effect when character lands:

public class LandDust : MonoBehaviour
{
    public ParticleSystem dustParticles;
    void OnCollisionEnter(Collision collision)
    {
        if (collision.gameObject.CompareTag("Ground"))
        {
            dustParticles.Play();
        }
    }
}

Important Particle Settings

Setting	Location	Effect
Looping	Main	Effect repeats (fire, rain) or plays once (explosion)
Start Lifetime	Main	Defines how long each particle lives (in seconds)
Start Speed	Main	Sets the initial speed of particles
Rate over Time	Emission	Controls number of particles spawned per second
Burst	Emission	Spawns particles instantly in a burst
Gravity Modifier	Main	Applies gravity to particles (negative = upward motion)

Changing Particle Texture

By default, particles are white dots. Use any image as particle.

Import a PNG texture (star, smoke, leaf)
Select Particle System - Renderer module
Drag texture into "Material" slot

Common Use Cases

Fire

Cone shape emission
Colors: orange - red fade
Moves upward (rising effect)

Smoke

Sphere shape emission
Particles grow larger over time
Gradually fade out

Rain

Box shape emission
High speed downward movement
Small particle size