ScienceLab.GravityForce/Assets/Materials/Scripts/CameraController.cs

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

public class CameraController : MonoBehaviour
{
    public Camera mainCamera;
    public float transitionSpeed = 3f;

    public float planetDistance = 15f;
    public float planetHeight = 5f;
    public float rotationSpeed = 100f;

    public float cameraLocalX = 1.76f;
    public float cameraLocalY = 1.14f;
    public float cameraLocalZ = -1.51f;
    public Vector3 cameraLocalRotation;

    public float sunZoomSpeed = 10f;
    public float sunMinZ = -200f;
    public float sunMaxZ = -5f;

    private Dictionary<int, GameObject> _planets = new Dictionary<int, GameObject>();
    private GameObject _sun;
    private int _currentIndex = 0;
    private bool _isTransitioning = false;

    private float _currentPlanetDistance;
    private float _planetRotationY = 0f;
    private float _planetRotationX = 20f;

    void Start()
    {
        _sun = GameObject.Find("Sun");

        FindPlanetByName(1, "Mercury");
        FindPlanetByName(2, "Venus");
        FindPlanetByName(3, "Earth");
        FindPlanetByName(4, "Mars");
        FindPlanetByName(5, "Jupiter");
        FindPlanetByName(6, "Saturn");
        FindPlanetByName(7, "Uranus");
        FindPlanetByName(8, "Neptune");
        FindPlanetByName(9, "Pluto");

        _currentPlanetDistance = planetDistance;

        ShowOverview();
    }

    void FindPlanetByName(int key, string planetName)
    {
        GameObject planet = GameObject.Find(planetName);
        if (planet != null)
            _planets[key] = planet;
    }

    void Update()
    {
        HandleInput();

        if (!_isTransitioning && _currentIndex != 0)
            HandlePlanetCamera();

        if (!_isTransitioning && _currentIndex == 0)
            HandleSunZoom();
    }

    void HandleInput()
    {
        if (Input.GetKeyDown(KeyCode.Alpha0) || Input.GetKeyDown(KeyCode.Keypad0))
            ShowOverview();

        if (Input.GetKeyDown(KeyCode.Alpha1) || Input.GetKeyDown(KeyCode.Keypad1)) FocusPlanet(1);
        if (Input.GetKeyDown(KeyCode.Alpha2) || Input.GetKeyDown(KeyCode.Keypad2)) FocusPlanet(2);
        if (Input.GetKeyDown(KeyCode.Alpha3) || Input.GetKeyDown(KeyCode.Keypad3)) FocusPlanet(3);
        if (Input.GetKeyDown(KeyCode.Alpha4) || Input.GetKeyDown(KeyCode.Keypad4)) FocusPlanet(4);
        if (Input.GetKeyDown(KeyCode.Alpha5) || Input.GetKeyDown(KeyCode.Keypad5)) FocusPlanet(5);
        if (Input.GetKeyDown(KeyCode.Alpha6) || Input.GetKeyDown(KeyCode.Keypad6)) FocusPlanet(6);
        if (Input.GetKeyDown(KeyCode.Alpha7) || Input.GetKeyDown(KeyCode.Keypad7)) FocusPlanet(7);
        if (Input.GetKeyDown(KeyCode.Alpha8) || Input.GetKeyDown(KeyCode.Keypad8)) FocusPlanet(8);
        if (Input.GetKeyDown(KeyCode.Alpha9) || Input.GetKeyDown(KeyCode.Keypad9)) FocusPlanet(9);

        if (Input.GetKeyDown(KeyCode.RightArrow)) NextPlanet();
        if (Input.GetKeyDown(KeyCode.LeftArrow)) PreviousPlanet();
    }

    void ShowOverview()
    {
        _currentIndex = 0;
        StopAllCoroutines();
        StartCoroutine(TransitionToSun());
    }

    void FocusPlanet(int planetNumber)
    {
        if (!_planets.ContainsKey(planetNumber)) return;

        _currentIndex = planetNumber;
        StopAllCoroutines();
        StartCoroutine(TransitionToPlanet(planetNumber));
    }

    void NextPlanet()
    {
        _currentIndex++;
        if (_currentIndex > 9) _currentIndex = 0;
        if (_currentIndex == 0) ShowOverview();
        else FocusPlanet(_currentIndex);
    }

    void PreviousPlanet()
    {
        _currentIndex--;
        if (_currentIndex < 0) _currentIndex = 9;
        if (_currentIndex == 0) ShowOverview();
        else FocusPlanet(_currentIndex);
    }

    IEnumerator TransitionToSun()
    {
        _isTransitioning = true;

        if (_sun == null)
        {
            _isTransitioning = false;
            yield break;
        }

        Vector3 startPos = mainCamera.transform.position;
        Quaternion startRot = mainCamera.transform.rotation;

        Vector3 targetWorldPos = _sun.transform.TransformPoint(
            new Vector3(cameraLocalX, cameraLocalY, cameraLocalZ)
        );
        Quaternion targetWorldRot = _sun.transform.rotation * Quaternion.Euler(cameraLocalRotation);

        float elapsed = 0f;
        float duration = 1f / transitionSpeed;

        while (elapsed < duration)
        {
            elapsed += Time.deltaTime;
            float t = Mathf.SmoothStep(0, 1, elapsed / duration);

            mainCamera.transform.position = Vector3.Lerp(startPos, targetWorldPos, t);
            mainCamera.transform.rotation = Quaternion.Slerp(startRot, targetWorldRot, t);

            yield return null;
        }

        mainCamera.transform.SetParent(_sun.transform);
        mainCamera.transform.localPosition = new Vector3(cameraLocalX, cameraLocalY, cameraLocalZ);
        mainCamera.transform.localRotation = Quaternion.Euler(cameraLocalRotation);

        _isTransitioning = false;
    }

    void HandleSunZoom()
    {
        if (mainCamera.transform.parent != _sun.transform) return;

        float scroll = Input.GetAxis("Mouse ScrollWheel");
        if (Mathf.Abs(scroll) < 0.001f) return;

        cameraLocalZ += scroll * sunZoomSpeed;
        cameraLocalZ = Mathf.Clamp(cameraLocalZ, sunMinZ, sunMaxZ);

        mainCamera.transform.localPosition = new Vector3(
            cameraLocalX,
            cameraLocalY,
            cameraLocalZ
        );
    }

    IEnumerator TransitionToPlanet(int planetNumber)
    {
        _isTransitioning = true;

        Transform planet = _planets[planetNumber].transform;

        mainCamera.transform.SetParent(null);

        Vector3 startPos = mainCamera.transform.position;
        Quaternion startRot = mainCamera.transform.rotation;

        _currentPlanetDistance = planetDistance;
        Vector3 localTargetPos = new Vector3(0, planetHeight, -_currentPlanetDistance);
        Vector3 worldTargetPos = planet.TransformPoint(localTargetPos);
        Quaternion targetRot = Quaternion.LookRotation(planet.position - worldTargetPos);

        float elapsed = 0f;
        float duration = 1f / transitionSpeed;

        while (elapsed < duration)
        {
            elapsed += Time.deltaTime;
            float t = Mathf.SmoothStep(0, 1, elapsed / duration);

            mainCamera.transform.position = Vector3.Lerp(startPos, worldTargetPos, t);
            mainCamera.transform.rotation = Quaternion.Slerp(startRot, targetRot, t);

            yield return null;
        }

        mainCamera.transform.SetParent(planet);
        mainCamera.transform.localPosition = localTargetPos;
        mainCamera.transform.LookAt(planet.position);

        _planetRotationY = 0f;
        _planetRotationX = planetHeight > 0 ? 20f : 0f;

        _isTransitioning = false;
    }

    void HandlePlanetCamera()
    {
        if (!_planets.ContainsKey(_currentIndex)) return;

        Transform planet = _planets[_currentIndex].transform;

        if (Input.GetMouseButton(1))
        {
            _planetRotationY += Input.GetAxis("Mouse X") * rotationSpeed * Time.deltaTime;
            _planetRotationX -= Input.GetAxis("Mouse Y") * rotationSpeed * Time.deltaTime;
            _planetRotationX = Mathf.Clamp(_planetRotationX, -85f, 85f);
        }

        float scroll = Input.GetAxis("Mouse ScrollWheel");
        _currentPlanetDistance -= scroll * 10f;
        _currentPlanetDistance = Mathf.Clamp(_currentPlanetDistance, 3f, 100f);

        Quaternion rotation = Quaternion.Euler(_planetRotationX, _planetRotationY, 0);
        Vector3 localPos = rotation * new Vector3(0, 0, -_currentPlanetDistance);

        mainCamera.transform.localPosition = localPos;
     Vector3 direction = planet.position - mainCamera.transform.position;
mainCamera.transform.rotation =
    Quaternion.LookRotation(direction, planet.up);
    }
}