Version: 2018.4
public bool allowRoll ;

Description

Allow billboard particles to roll around their Z axis.

Allows billboards to roll with the camera. It is often useful to disable this option when using VR, to give particles a more believable grounding in the world.

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour {

private ParticleSystemRenderer psr; public bool allowRoll = true;

void Start() { psr = GetComponent<ParticleSystemRenderer>(); psr.material = new Material(Shader.Find("Sprites/Default")); }

void Update() { var psr = GetComponent<ParticleSystemRenderer>(); psr.allowRoll = allowRoll;

Camera.main.transform.rotation = Quaternion.Euler(0.0f, 0.0f, Mathf.Sin(Time.time * 0.2f) * 90.0f); }

void OnGUI() { allowRoll = GUI.Toggle(new Rect(25, 45, 200, 30), allowRoll, "Allow Roll"); } }