Version: 2019.1
public ParticleSystem.ColorBySpeedModule colorBySpeed ;

Description

Script interface for the Particle System color by lifetime module.

This module assigns colors to the particles based on the speed that they are travelling.

Particle System modules do not need to be reassigned back to the system; they are interfaces and not independent objects.

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour { void Start() { ParticleSystem ps = GetComponent<ParticleSystem>(); var col = ps.colorBySpeed; col.enabled = true;

Gradient grad = new Gradient(); grad.SetKeys( new GradientColorKey[] { new GradientColorKey(Color.blue, 0.0f), new GradientColorKey(Color.red, 1.0f) }, new GradientAlphaKey[] { new GradientAlphaKey(1.0f, 0.0f), new GradientAlphaKey(0.0f, 1.0f) } );

col.color = grad; } }