ボタンなどを押さなかった時のタッチイベントを取得する【Unity】【uGUI】

TouchEventHandler.cs

//  TouchEventHandler.cs
//  http://kan-kikuchi.hatenablog.com/entry/uGUI_TouchEventHandler
//
//  Created by kan.kikuchi on 2016.04.20.

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

/// <summary>
/// タッチ判定をハンドリングするクラス
/// </summary>
public class TouchEventHandler : SingletonMonoBehaviour<TouchEventHandler>,
IPointerDownHandler,
IPointerUpHandler,
IBeginDragHandler,
IEndDragHandler,
IDragHandler{

  //タップ中
  private bool _isPressing = false;
  public  bool  IsPressing{
    get{return _isPressing;}
  }

  //ドラック中か
  private bool _isDragging = false;
  public  bool  IsDragging{
    get{return _isDragging;}
  }

  //ピンチ中かのフラグ
  private bool _isPinching = false;
  public  bool  IsPinching{
    get{return _isPinching;}
  }

  //全フレームでのドラック位置(ワールド座標)
  private Vector3 _beforeTapWorldPoint;

  //ピンチ開始時の指の距離
  private float _beforeDistanceOfPinch;

  //タップ関係
  public event Action<bool> onPress       = delegate {};
  public event Action        onBeginPress  = delegate {};
  public event Action        onEndPress    = delegate {};

  //ドラッグ
  public event Action<Vector2> onDrag      = delegate {};
  public event Action<Vector3> onDragIn3D  = delegate {};
  public event Action          onBeginDrag = delegate {};
  public event Action          onEndDrag   = delegate {};

  //ビンチ
  public event Action<float> onPinch      = delegate {};
  public event Action        onBeginPinch = delegate {};
  public event Action        onEndPinch   = delegate {};

  //ドラッグしている指のデータ
  private Dictionary<int, PointerEventData> _draggingDataDict = new Dictionary<int, PointerEventData>();

  //=================================================================================
  //タップ
  //=================================================================================

  /// <summary>
  /// タップ開始時
  /// </summary>
  public void OnPointerDown (PointerEventData eventData){
    _isPressing = true;

    onBeginPress ();
    onPress (true);
  }

  /// <summary>
  /// タップ終了時
  /// </summary>
  public void OnPointerUp (PointerEventData eventData){
    _isPressing = false;

    onEndPress ();
    onPress (false);

    //ピンチ終了イベント実行
    if(_isPinching && _draggingDataDict.Count < 2){
      _isPinching = false;
      onEndPinch ();
    }
  }

  //=================================================================================
  //ドラッグ
  //=================================================================================

  /// <summary>
  /// ドラッグ開始時
  /// </summary>
  public void OnBeginDrag(PointerEventData eventData){
    if(!_isDragging){
      _beforeTapWorldPoint = GetTapWorldPoint ();
    }

    _isDragging = true;
    onBeginDrag ();

    //ドラッグデータ追加
    _draggingDataDict[eventData.pointerId] = eventData;
  }

  /// <summary>
  /// ドラッグ終了時
  /// </summary>
  public void OnEndDrag (PointerEventData eventData){
    _isDragging = false;
    onEndDrag ();

    //ドラッグデータ削除
    if(_draggingDataDict.ContainsKey(eventData.pointerId)){
      _draggingDataDict.Remove (eventData.pointerId);
    }
  }

  /// <summary>
  /// ドラッグ中
  /// </summary>
  public void OnDrag (PointerEventData eventData){
    if (!_isDragging) {
      OnBeginDrag (eventData);
      return;
    }

    //ドラッグデータ更新
    _draggingDataDict[eventData.pointerId] = eventData;

    //2本以上ドラッグデータがある時はピンチ
    if(_draggingDataDict.Count >= 2){
      //ドラック中だった場合は終了する
      if(_isDragging){
        _isDragging = false;
        onEndDrag ();
      }

      OnPinch ();
    }
    //指が一本だけの時だけドラッグ(PC上では0本)
    else if(Input.touches.Length <= 1){

      //ピンチの状態からすぐ移ってきた場合はピンチの終了処理、ドラッグの開始処理をする
      if(_isPinching){
        _isDragging = false;
        _isPinching = false;
        onEndPinch ();
        OnBeginDrag (eventData);
      }

      onDrag (eventData.delta);
      OnDragInWorldPoint ();
    }
  }

  /// <summary>
  /// ドラッグ中(座標をワールド座標で返す)
  /// </summary>
  public void OnDragInWorldPoint (){
    Vector3 tapWorldPoint = GetTapWorldPoint ();
    onDragIn3D (tapWorldPoint - _beforeTapWorldPoint);
    _beforeTapWorldPoint = tapWorldPoint;
  }

  //タップしている場所をワールド座標で取得
  private Vector3 GetTapWorldPoint(){
    //タップ位置を画面内の座標に変換
    Vector2 screenPos = Vector2.zero;
    RectTransformUtility.ScreenPointToLocalPointInRectangle(GetComponent<RectTransform>(), 
      new Vector2(Input.mousePosition.x, Input.mousePosition.y),
      null,
      out screenPos
    );

    //ワールド座標に変換
    Vector3 tapWorldPoint = Camera.main.ScreenToWorldPoint (
      new Vector3(screenPos.x, screenPos.y, -Camera.main.transform.position.z)
    );

    return tapWorldPoint;
  }

  //=================================================================================
  //ピンチ
  //=================================================================================

  //ピンチ中
  private void OnPinch(){

    //最初と2本目のタッチ情報取得
    Vector2 firstTouch = Vector2.zero, secondTouch = Vector2.zero;
    int count = 0;

    foreach (var draggingData in _draggingDataDict) {
      if(count == 0){
        firstTouch = draggingData.Value.position;
        count = 1;
      }
      else if(count == 1){
        secondTouch = draggingData.Value.position;
        break;
      }
    }

    //ピンチの幅を取得
    float distanceOfPinch = Vector2.Distance (firstTouch, secondTouch); 

    //ピンチ開始
    if(!_isPinching){
      _isPinching = true;
      _beforeDistanceOfPinch = distanceOfPinch;

      onBeginPinch ();
      return;
    }

    //現在地の座標差も算出し、座標差からピンチの倍率を計算
    float pinchiDiff   = distanceOfPinch -   _beforeDistanceOfPinch;
    onPinch(pinchiDiff);


    _beforeDistanceOfPinch = distanceOfPinch;
  }

}