Floating origin to handle large worlds in Unity.

FloatingOrigin.cs

  This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.

Learn more about bidirectional Unicode characters

Show hidden characters

// Based on the Unity Wiki FloatingOrigin script by Peter Stirling

// URL: http://wiki.unity3d.com/index.php/Floating_Origin

using UnityEngine;

using UnityEngine.SceneManagement;

public class FloatingOrigin : MonoBehaviour

{

    [Tooltip("Point of reference from which to check the distance to origin.")]

    public Transform ReferenceObject = null;

    [Tooltip("Distance from the origin the reference object must be in order to trigger an origin shift.")]

    public float Threshold = 5000f;

    [Header("Options")]

    [Tooltip("When true, origin shifts are considered only from the horizontal distance to orign.")]

    public bool Use2DDistance = false;

    [Tooltip("When true, updates ALL open scenes. When false, updates only the active scene.")]

    public bool UpdateAllScenes = true;

    [Tooltip("Should ParticleSystems be moved with an origin shift.")]

    public bool UpdateParticles = true;

    [Tooltip("Should TrailRenderers be moved with an origin shift.")]

    public bool UpdateTrailRenderers = true;

    [Tooltip("Should LineRenderers be moved with an origin shift.")]

    public bool UpdateLineRenderers = true;

    private ParticleSystem.Particle[] parts = null;

    void LateUpdate()

    {

        if (ReferenceObject == null)

            return;

        Vector3 referencePosition = ReferenceObject.position;

        if (Use2DDistance)

            referencePosition.y = 0f;

        if (referencePosition.magnitude > Threshold)

        {

            MoveRootTransforms(referencePosition);

            if (UpdateParticles)

                MoveParticles(referencePosition);

            if (UpdateTrailRenderers)

                MoveTrailRenderers(referencePosition);

            if (UpdateLineRenderers)

                MoveLineRenderers(referencePosition);

        }

    }

    private void MoveRootTransforms(Vector3 offset)

    {

        if (UpdateAllScenes)

        {

            for (int z = 0; z < SceneManager.sceneCount; z++)

            {

                foreach (GameObject g in SceneManager.GetSceneAt(z).GetRootGameObjects())

                    g.transform.position -= offset;

            }

        }

        else

        {

            foreach (GameObject g in SceneManager.GetActiveScene().GetRootGameObjects())

                g.transform.position -= offset;

        }

    }

    private void MoveTrailRenderers(Vector3 offset)

    {

        var trails = FindObjectsOfType<TrailRenderer>() as TrailRenderer[];

        foreach (var trail in trails)

        {

            Vector3[] positions = new Vector3[trail.positionCount];

            int positionCount = trail.GetPositions(positions);

            for (int i = 0; i < positionCount; ++i)

                positions[i] -= offset;

            trail.SetPositions(positions);

        }

    }

    private void MoveLineRenderers(Vector3 offset)

    {

        var lines = FindObjectsOfType<LineRenderer>() as LineRenderer[];

        foreach (var line in lines)

        {

            Vector3[] positions = new Vector3[line.positionCount];

            int positionCount = line.GetPositions(positions);

            for (int i = 0; i < positionCount; ++i)

                positions[i] -= offset;

            line.SetPositions(positions);

        }

    }

    private void MoveParticles(Vector3 offset)

    {

        var particles = FindObjectsOfType<ParticleSystem>() as ParticleSystem[];

        foreach (ParticleSystem system in particles)

        {

            if (system.main.simulationSpace != ParticleSystemSimulationSpace.World)

                continue;

            int particlesNeeded = system.main.maxParticles;

            if (particlesNeeded <= 0)

                continue;

            // ensure a sufficiently large array in which to store the particles

            if (parts == null || parts.Length < particlesNeeded)

            {

                parts = new ParticleSystem.Particle[particlesNeeded];

            }

            // now get the particles

            int num = system.GetParticles(parts);

            for (int i = 0; i < num; i++)

            {

                parts[i].position -= offset;

            }

            system.SetParticles(parts, num);

        }

    }

}