ParticleSystem.LightsModule.maxLights

Description

Set a limit on how many lights this Module can create.

This value is useful for avoiding bad performance, due to how easy it can be to create lots of lights.

using UnityEngine;
using System.Collections;

// For best results, use Deferred Rendering (see Camera settings)
public class ExampleClass : MonoBehaviour
{
    private ParticleSystem ps;
    public Light lightPrefab;     // Provide a light Prefab in the inspector
    public float hSliderValueRatio = 1.0f;
    public float hSliderValueMax = 1000.0f;
    public bool randomDistribution = true;

    void Start()
    {
        ps = GetComponent<ParticleSystem>();
        ps.transform.localRotation = Quaternion.Euler(0.0f, 0.0f, 45.0f);

        var shape = ps.shape;
        shape.shapeType = ParticleSystemShapeType.Circle;

        var lights = ps.lights;
        lights.enabled = true;
        lights.light = lightPrefab;

        // plane to receive lights
        var plane = GameObject.CreatePrimitive(PrimitiveType.Plane);
        plane.transform.parent = ps.transform;
        plane.transform.localPosition = new Vector3(0.0f, 0.0f, 3.0f);
        plane.transform.localScale = new Vector3(20.0f, 20.0f, 20.0f);
        plane.transform.localRotation = Quaternion.Euler(-90.0f, 0.0f, 0.0f);

        var material = new Material(Shader.Find("Standard"));
        material.color = new Color(0.1f, 0.1f, 0.1f, 1.0f);
        plane.GetComponent<MeshRenderer>().material = material;
    }

    void Update()
    {
        var lights = ps.lights;
        lights.ratio = hSliderValueRatio;
        lights.maxLights = (int)hSliderValueMax;
        lights.useRandomDistribution = randomDistribution;
    }

    void OnGUI()
    {
        GUI.Label(new Rect(25, 40, 100, 30), "Ratio");
        GUI.Label(new Rect(25, 80, 100, 30), "Max Lights");

        hSliderValueRatio = GUI.HorizontalSlider(new Rect(95, 45, 100, 30), hSliderValueRatio, 0.0f, 1.0f);
        hSliderValueMax = GUI.HorizontalSlider(new Rect(95, 85, 100, 30), hSliderValueMax, 0.0f, 500.0f);

        randomDistribution = GUI.Toggle(new Rect(25, 125, 400, 30), randomDistribution, "Randomly assign Lights to Particles instead of evenly distributing them.");
    }
}