VR空間内をデバッグできるようにマウスで移動する

概要

VR開発をしていると、HMDをかぶるのが意外と手間になります。
そこで、マウスで位置や回転を制御できると便利です。

ということで、カメラに適用しておくとさっと動かせるスクリプトを残しておきます。
こんな感じ↓

using UnityEngine;
using System.Collections;

/// <summary>
/// マウスでカメラの位置、回転を制御する
/// </summary>
public class MouseCameraController : MonoBehaviour
{
    enum DragType
    {
        Move,
        Rotate,
    }

    private bool _isDragging = false;
    private Vector3 _prevPos = Vector3.zero;
    private DragType _currenType;
    private float _speedLimit = 100f;
    private Quaternion _originalRot;

    private float _x = 0f;
    private float _y = 0f;

    [SerializeField][Range(0f, 10f)]
    private float _moveSpeed = 5f;

    [SerializeField][Range(0f, 10f)]
    private float _rotateSpeed = 5f;

    [SerializeField]
    private Transform _controlTarget;
    private Transform ControlTarget
    {
        get
        {
            if (!_controlTarget)
            {
                _controlTarget = transform;
            }

            return _controlTarget;
        }
    }


    #region MonoBehaviour
    void Start()
    {
        _originalRot = ControlTarget.rotation;
    }
    
    void Update()
    {
        float wheelval = Input.GetAxis("Mouse ScrollWheel");

        Vector3 pos = ControlTarget.position;
        pos += ControlTarget.forward * wheelval * 2f;
        ControlTarget.position = pos;

        if (Input.GetMouseButtonDown(0))
        {
            OnMouseDown(DragType.Move);
        }

        if (Input.GetMouseButtonDown(1))
        {
            OnMouseDown(DragType.Rotate);
        }

        if (Input.GetMouseButtonUp(0) || Input.GetMouseButtonUp(1))
        {
            OnMouseUp();
        }

        OnMouseMove();
    }
    #endregion


    void OnMouseDown(DragType type)
    {
        _isDragging = true;
        _currenType = type;
        _prevPos = Input.mousePosition;
    }

    void OnMouseUp()
    {
        _isDragging = false;
    }

    void OnMouseMove()
    {
        if (!_isDragging)
        {
            return;
        }

        Vector3 delta = Input.mousePosition - _prevPos;
        _prevPos = Input.mousePosition;

        switch (_currenType)
        {
            case DragType.Move:
                delta *= (_moveSpeed / _speedLimit);

                Vector3 pos = ControlTarget.position;
                pos += ControlTarget.up * -delta.y;
                pos += ControlTarget.right * delta.x;

                ControlTarget.position = pos;

                return;

            case DragType.Rotate:
                delta *= (_rotateSpeed / _speedLimit);

                _x += delta.x;
                if (_x <= -180)
                {
                    _x += 360;
                }
                else if (_x > 180)
                {
                    _x -= 360;
                }

                _y -= delta.y;
                _y = Mathf.Clamp(_y, -85f, 85f);

                ControlTarget.rotation = _originalRot * Quaternion.Euler(_y, _x, 0f);

                return;
        }

    }
}