Unity用かんたんカメラ動かすやつ

FollowingCamera.cs

// These codes are licensed under CC0.
// http://creativecommons.org/publicdomain/zero/1.0/deed.ja

using UnityEngine;

/// <summary>
/// The camera added this script will follow the specified object.
/// The camera can be moved by left mouse drag and mouse wheel.
/// </summary>
[ExecuteInEditMode, DisallowMultipleComponent]
public class FollowingCamera : MonoBehaviour
{
    public GameObject target; // an object to follow
    public Vector3 offset; // offset form the target object

    [SerializeField] private float distance = 1.0f; // distance from following object
    [SerializeField] private float polarAngle = 90.0f; // angle with y-axis
    [SerializeField] private float azimuthalAngle = 90.0f; // angle with x-axis

    [SerializeField] private float minDistance = 0.01f;
    [SerializeField] private float maxDistance = 7.0f;
    [SerializeField] private float minPolarAngle = 5.0f;
    [SerializeField] private float maxPolarAngle = 170.0f;
    [SerializeField] private Vector2 mouseTiltSensitivity = new Vector2( 5.0f,  5.0f);
    [SerializeField] private float scrollSensitivity = 0.5f;
    [SerializeField] private Vector2 mouseMoveSensitivity = new Vector2(0.05f, 0.05f);

    void LateUpdate()
    {
        if (Input.GetMouseButton(1)) {
            updateAngle(Input.GetAxis("Mouse X"), Input.GetAxis("Mouse Y"));
        }
        if (Input.GetMouseButton(2)) {
            updateOffset(Input.GetAxis("Mouse X"), Input.GetAxis("Mouse Y"));
        }
        updateDistance(Input.GetAxis("Mouse ScrollWheel"));

        var lookAtPos = target.transform.position + offset;
        updatePosition(lookAtPos);
        transform.LookAt(lookAtPos);
    }

    void updateAngle(float x, float y)
    {
        x = azimuthalAngle - x * mouseTiltSensitivity.x;
        azimuthalAngle = Mathf.Repeat(x, 360);

        y = polarAngle + y * mouseTiltSensitivity.y;
        polarAngle = Mathf.Clamp(y, minPolarAngle, maxPolarAngle);
    }

    void updateOffset(float x, float y)
    {
        offset += transform.rotation * new Vector3(- x * mouseMoveSensitivity.x, - y * mouseMoveSensitivity.y, 0);
    }

    void updateDistance(float scroll)
    {
        scroll = distance - scroll * scrollSensitivity;
        distance = Mathf.Clamp(scroll, minDistance, maxDistance);
    }

    void updatePosition(Vector3 lookAtPos)
    {
        var da = azimuthalAngle * Mathf.Deg2Rad;
        var dp = polarAngle * Mathf.Deg2Rad;
        transform.position = new Vector3(
            lookAtPos.x + distance * Mathf.Sin(dp) * Mathf.Cos(da),
            lookAtPos.y + distance * Mathf.Cos(dp),
            lookAtPos.z + distance * Mathf.Sin(dp) * Mathf.Sin(da));
    }
}