Sub-emitters in Unity

Introduction

Sub-emitters let you create extra particle effects that start when main particles die or collide. This helps make effects look more natural and exciting.

When you want sparks to fly out after a firework explodes.

To create smoke puffs after a bullet hits a surface.

For adding small explosions after a big explosion fades.

When particles should trigger other effects on collision.

To chain particle effects for more complex visuals.

Syntax

Unity

ParticleSystem subEmitter = mainParticleSystem.subEmitters.AddSubEmitter(subEmitterPrefab, SubEmitterType.Birth, SubEmitterProperties.InheritColor);

Use SubEmitterType to decide when the sub-emitter triggers: on Birth, Collision, or Death of the main particle.

Sub-emitters are added to the main particle system's subEmitters property.

Examples

Adds a smoke effect that starts when each main particle dies.

Unity

mainParticleSystem.subEmitters.AddSubEmitter(smokePrefab, SubEmitterType.Death, SubEmitterProperties.None);

Adds sparks that appear when particles collide, inheriting the main particle's color.

Unity

mainParticleSystem.subEmitters.AddSubEmitter(sparkPrefab, SubEmitterType.Collision, SubEmitterProperties.InheritColor);

Creates a flash effect every time a new particle is born, inheriting its lifetime.

Unity

mainParticleSystem.subEmitters.AddSubEmitter(flashPrefab, SubEmitterType.Birth, SubEmitterProperties.InheritLifetime);

Sample Program

This script adds a sub-emitter to the main particle system. The sub-emitter plays its effect whenever a main particle dies, such as smoke or sparks. It then starts the main particle system.

Unity

using UnityEngine;

public class SubEmitterExample : MonoBehaviour
{
    public ParticleSystem mainParticleSystem;
    public ParticleSystem subEmitterPrefab;

    void Start()
    {
        // Add a sub-emitter that triggers when main particles die
        mainParticleSystem.subEmitters.AddSubEmitter(subEmitterPrefab, SubEmitterType.Death, SubEmitterProperties.None);

        // Start the main particle system
        mainParticleSystem.Play();
    }
}

Important Notes

Sub-emitters only work if the main particle system has subEmitters enabled.

Remember to assign the sub-emitter prefab in the Unity Editor or by script before adding it.

Sub-emitters can affect performance if overused, so use them wisely.

Summary

Sub-emitters create extra particle effects triggered by main particles.

They can start on particle birth, collision, or death.

Use them to make effects more dynamic and realistic.