*event system鍒濇帰

1 files changed, 14 insertions, 10 deletions

diff --git a/Assets/uGUI-2017.1/UnityEngine.UI/EventSystem/InputModules/PointerInputModule.cs b/Assets/uGUI-2017.1/UnityEngine.UI/EventSystem/InputModules/PointerInputModule.cs
index d31f433..9103162 100644
--- a/Assets/uGUI-2017.1/UnityEngine.UI/EventSystem/InputModules/PointerInputModule.cs
+++ b/Assets/uGUI-2017.1/UnityEngine.UI/EventSystem/InputModules/PointerInputModule.cs
@@ -16,7 +16,7 @@ namespace UnityEngine.EventSystems
 
         protected bool GetPointerData(int id, out PointerEventData data, bool create)
         {
-            if (!m_PointerData.TryGetValue(id, out data) && create)
+            if (!m_PointerData.TryGetValue(id, out data) && create) // 一个池子
             {
                 data = new PointerEventData(eventSystem)
                 {
@@ -33,29 +33,33 @@ namespace UnityEngine.EventSystems
             m_PointerData.Remove(data.pointerId);
         }
 
+        //c 根据touch数据得到pointEventData，并且保存raycaster结果
         protected PointerEventData GetTouchPointerEventData(Touch input, out bool pressed, out bool released)
         {
             PointerEventData pointerData;
-            var created = GetPointerData(input.fingerId, out pointerData, true);
+            var created = GetPointerData(input.fingerId, out pointerData, true); // 拿到存储结构，返回是否是新建结构
 
             pointerData.Reset();
 
-            pressed = created || (input.phase == TouchPhase.Began);
-            released = (input.phase == TouchPhase.Canceled) || (input.phase == TouchPhase.Ended);
+            // pressed和released用来判断抬起或者放下
 
-            if (created)
+            pressed = created || (input.phase == TouchPhase.Began); // 如果结构是新建的或input phase是bagan，说明是刚按下
+            released = (input.phase == TouchPhase.Canceled) || (input.phase == TouchPhase.Ended); // 如果phase是这两种，说明是抬起来了
+
+            if (created)//如果是新建的，记录下起始位置，否则还保留旧值，下面用来计算delta
                 pointerData.position = input.position;
 
-            if (pressed)
+            if (pressed)//如果是刚按下，delta置为0
                 pointerData.delta = Vector2.zero;
             else
-                pointerData.delta = input.position - pointerData.position;
+                pointerData.delta = input.position - pointerData.position; // 计算delta
 
-            pointerData.position = input.position;
+            pointerData.position = input.position; // 计算完delta后覆盖
 
-            pointerData.button = PointerEventData.InputButton.Left;
+            pointerData.button = PointerEventData.InputButton.Left; // 这里不知道为什么
 
-            eventSystem.RaycastAll(pointerData, m_RaycastResultCache);
+            // 用这个触摸数据做射线检测，检测结果在m_RaycastResultCache
+            eventSystem.RaycastAll(pointerData, m_RaycastResultCache); 
 
             var raycast = FindFirstRaycast(m_RaycastResultCache);
             pointerData.pointerCurrentRaycast = raycast;