ScienceLab.AtmosphericPressure/Assets/Scripts/MarsExosphereEffects.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class MarsExosphereEffects : MonoBehaviour
{
    public Material ruptureMaterial;
    public Material escapeMaterial;

    [Range(0f, 1f)]
    public float exosphereLevel = 1f;

    private float previousLevel = 1f;

    private ParticleSystem ruptureSystem;
    private ParticleSystem escapeSystem;

    private bool deathTriggered = false;

    private MarsDeath marsDeath;

    void Awake()
    {
        enabled = false;
    }

    public void InitState()
    {
        if (ruptureSystem != null) Destroy(ruptureSystem.gameObject);
        if (escapeSystem != null) Destroy(escapeSystem.gameObject);

        ruptureSystem = null;
        escapeSystem = null;

        marsDeath = GetComponentInParent<MarsDeath>();

        exosphereLevel = 1f;
        previousLevel = 1f;
        deathTriggered = false;

        CreateSystems();
    }

    void Update()
    {
        if (!Application.isPlaying) return;

        if (exosphereLevel >= 1f && previousLevel < 1f)
            ResetState();

        previousLevel = exosphereLevel;

        if (exosphereLevel <= 0f && !deathTriggered)
        {
            deathTriggered = true;

            if (marsDeath != null)
                marsDeath.mesosphereLevel = 0f;

            StartCoroutine(DeathBurst());
            return;
        }

        if (deathTriggered) return;

        UpdateRupture();
        UpdateEscape();
    }

    void ResetState()
    {
        deathTriggered = false;

        if (marsDeath != null)
            marsDeath.ResetTexture();

        if (ruptureSystem != null)
        {
            var e = ruptureSystem.emission;
            e.rateOverTime = 0;
        }

        if (escapeSystem != null)
        {
            var e = escapeSystem.emission;
            e.rateOverTime = 0;
        }
    }

    void CreateSystems()
    {
        GameObject r = new GameObject("Rupture");
        r.transform.position = transform.position;
        ruptureSystem = r.AddComponent<ParticleSystem>();

        var mainR = ruptureSystem.main;
        mainR.loop = true;
        mainR.startLifetime = new ParticleSystem.MinMaxCurve(0.4f, 1.2f);
        mainR.startSpeed = new ParticleSystem.MinMaxCurve(6f, 14f);
        mainR.startSize = new ParticleSystem.MinMaxCurve(0.05f, 0.2f);
        mainR.startColor = new ParticleSystem.MinMaxGradient(
            new Color(0.4f, 0.05f, 0.05f),
            new Color(0.7f, 0.1f, 0.1f)
        );
        mainR.simulationSpace = ParticleSystemSimulationSpace.World;

        var emissionR = ruptureSystem.emission;
        emissionR.rateOverTime = 0;

        var shapeR = ruptureSystem.shape;
        shapeR.enabled = true;
        shapeR.shapeType = ParticleSystemShapeType.Sphere;
        shapeR.radius = 3.5f;
        shapeR.radiusThickness = 0.05f;

        var noiseR = ruptureSystem.noise;
        noiseR.enabled = true;
        noiseR.strength = 2f;

        var velR = ruptureSystem.velocityOverLifetime;
        velR.enabled = true;
        velR.space = ParticleSystemSimulationSpace.World;
        velR.z = new ParticleSystem.MinMaxCurve(10f);

        if (ruptureMaterial != null)
            ruptureSystem.GetComponent<ParticleSystemRenderer>().material = ruptureMaterial;

        ruptureSystem.Play();

        GameObject e = new GameObject("Escape");
        e.transform.position = transform.position;
        escapeSystem = e.AddComponent<ParticleSystem>();

        var mainE = escapeSystem.main;
        mainE.loop = true;
        mainE.startLifetime = new ParticleSystem.MinMaxCurve(2f, 5f);
        mainE.startSpeed = new ParticleSystem.MinMaxCurve(15f, 40f);
        mainE.startSize = new ParticleSystem.MinMaxCurve(0.03f, 0.15f);
        mainE.startColor = new ParticleSystem.MinMaxGradient(
            new Color(0.3f, 0.05f, 0.05f),
            new Color(0.8f, 0.1f, 0.1f)
        );
        mainE.simulationSpace = ParticleSystemSimulationSpace.World;

        var emissionE = escapeSystem.emission;
        emissionE.rateOverTime = 0;

        var shapeE = escapeSystem.shape;
        shapeE.enabled = true;
        shapeE.shapeType = ParticleSystemShapeType.Sphere;
        shapeE.radius = 3.6f;
        shapeE.radiusThickness = 0.1f;

        var velE = escapeSystem.velocityOverLifetime;
        velE.enabled = true;
        velE.space = ParticleSystemSimulationSpace.World;
        velE.z = new ParticleSystem.MinMaxCurve(25f);

        if (escapeMaterial != null)
            escapeSystem.GetComponent<ParticleSystemRenderer>().material = escapeMaterial;

        escapeSystem.Play();
    }

    void UpdateRupture()
    {
        float t = Mathf.InverseLerp(1f, 0f, exosphereLevel);

        var e = ruptureSystem.emission;
        e.rateOverTime = Mathf.Lerp(0, 2000, t);

        if (Random.value < t * 0.5f)
            ruptureSystem.Emit(20);
    }

    void UpdateEscape()
    {
        float t = Mathf.InverseLerp(1f, 0f, exosphereLevel);

        var e = escapeSystem.emission;
        e.rateOverTime = Mathf.Lerp(0, 5000, t);
    }

    IEnumerator DeathBurst()
    {
        var e1 = ruptureSystem.emission;
        e1.rateOverTime = 7000;

        var e2 = escapeSystem.emission;
        e2.rateOverTime = 12000;

        yield return new WaitForSeconds(0.5f);

        var e3 = ruptureSystem.emission;
        e3.rateOverTime = 0;

        var e4 = escapeSystem.emission;
        e4.rateOverTime = 0;
    }

    public void CleanUp()
    {
        if (ruptureSystem != null) Destroy(ruptureSystem.gameObject);
        if (escapeSystem != null) Destroy(escapeSystem.gameObject);

        if (marsDeath != null)
            marsDeath.ResetTexture();

        enabled = false;
    }
}