refine raycast test for mobile

AwesomeUIWidgets/Assets/Scripts/RaycastableScene/DragRotate.cs

 using System;
+using System.Collections.Generic;
 using UnityEngine;
 using UnityEngine.EventSystems;
 using UInput = UnityEngine.Input;
                 return new Vector2(UInput.mousePosition.x, UInput.mousePosition.y);
             }
         }
+        
+        private static bool IsPointerOverUIObject(float x, float y) {
+            PointerEventData eventDataCurrentPosition = new PointerEventData(EventSystem.current);
+            eventDataCurrentPosition.position = new Vector2(x, y);
+            List<RaycastResult> results = new List<RaycastResult>();
+            EventSystem.current.RaycastAll(eventDataCurrentPosition, results);
+            return results.Count > 0;
+        }
 
         void OnMouseDown()
         {
             }
+
+            foreach (Touch touch in UInput.touches)
+            {
+                if (touch.phase == TouchPhase.Began)
+                {
+                    int id = touch.fingerId;
+                    if (IsPointerOverUIObject(touch.position.x, touch.position.y))
+                    {
+                        return;
+                    }
+                }
+            }
+
             
             _lastPosition = mousePosition;
         }