Cache m_Target camera component to avoid repeatedly calling GetComponent<>()

Author: JoJo2nd

PostProcessing/Editor/PostProcessLayerEditor.cs

@@ -38,6 +38,10 @@ sealed class PostProcessLayerEditor : BaseEditor<PostProcessLayer>
 
         Dictionary<PostProcessEvent, ReorderableList> m_CustomLists;
 
+        #if UNITY_2017_3_OR_NEWER
+        Camera m_TargetCameraComponent;
+        #endif
+
         static GUIContent[] s_AntialiasingMethodNames =
         {
             new GUIContent("No Anti-aliasing"),
@@ -75,6 +79,10 @@ void OnEnable()
 
             m_ShowToolkit = serializedObject.FindProperty("m_ShowToolkit");
             m_ShowCustomSorter = serializedObject.FindProperty("m_ShowCustomSorter");
+
+            #if UNITY_2017_3_OR_NEWER
+            m_TargetCameraComponent = m_Target.GetComponent<Camera>();
+            #endif
         }
 
         void OnDisable()
@@ -162,9 +170,10 @@ void DoAntialiasing()
                     if (RuntimeUtilities.isSinglePassStereoSelected)
                         EditorGUILayout.HelpBox("TAA requires Unity 2017.3+ for Single-pass stereo rendering support.", MessageType.Warning);
                     #endif
-                    var camera = m_Target.GetComponent<Camera>();
-                    if (camera.allowDynamicResolution)
+                    #if UNITY_2017_3_OR_NEWER
+                    if (m_TargetCameraComponent != null && m_TargetCameraComponent.allowDynamicResolution)
                         EditorGUILayout.HelpBox("TAA is not supported with Dynamic Resolution.", MessageType.Warning);
+                    #endif
 
                     EditorGUILayout.PropertyField(m_TaaJitterSpread);
                     EditorGUILayout.PropertyField(m_TaaStationaryBlending);