ParticleSystem.GetParticles

파라미터

반환

int The number of particles written to the input particle array (the number of particles currently alive).

설명

Gets the particles of this Particle System.

This method is allocation free as long the input "particles" array is preallocated once (see example below). The method only gets the particles that are currently alive in the Particle System when it is called, so it may only get a small part of the particles array.

See Also: Particle, SetParticles.

using UnityEngine;

[RequireComponent(typeof(ParticleSystem))]
public class ParticleFlow : MonoBehaviour
{
    ParticleSystem m_System;
    ParticleSystem.Particle[] m_Particles;
    public float m_Drift = 0.01f;

    private void LateUpdate()
    {
        InitializeIfNeeded();

        // GetParticles is allocation free because we reuse the m_Particles buffer between updates
        int numParticlesAlive = m_System.GetParticles(m_Particles);

        // Change only the particles that are alive
        for (int i = 0; i < numParticlesAlive; i++)
        {
            m_Particles[i].velocity += Vector3.up * m_Drift;
        }

        // Apply the particle changes to the Particle System
        m_System.SetParticles(m_Particles, numParticlesAlive);
    }

    void InitializeIfNeeded()
    {
        if (m_System == null)
            m_System = GetComponent<ParticleSystem>();

        if (m_Particles == null || m_Particles.Length < m_System.main.maxParticles)
            m_Particles = new ParticleSystem.Particle[m_System.main.maxParticles];
    }
}