ParticleSystem.ForceOverLifetimeModule.y

Description

The curve defining particle forces in the y-axis.

Additional resources: MinMaxCurve.

using UnityEngine;
using System.Collections;

[RequireComponent(typeof(ParticleSystem))]
public class ExampleClass : MonoBehaviour
{
    private ParticleSystem ps;
    public bool moduleEnabled = true;
    public float hSliderValue = 10.0f;

    void Start()
    {
        ps = GetComponent<ParticleSystem>();
    }

    void Update()
    {
        var forceOverLifetime = ps.forceOverLifetime;
        forceOverLifetime.enabled = moduleEnabled;
        forceOverLifetime.y = hSliderValue;
    }

    void OnGUI()
    {
        moduleEnabled = GUI.Toggle(new Rect(25, 45, 100, 30), moduleEnabled, "Enabled");
        hSliderValue = GUI.HorizontalSlider(new Rect(25, 85, 100, 30), hSliderValue, -50.0f, 50.0f);
    }
}