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03-UnrealEngine/Gameplay/UObject/UnrealSpecifiers/Meta/Enum/UseEnumValuesAsMaskValuesInEditor/UseEnumValuesAsMaskValuesInEditor.md

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+# UseEnumValuesAsMaskValuesInEditor
+
+- **功能描述：** 指定枚举值已经是位移后的值，而不是位标记的索引下标。
+- **使用位置：** UENUM
+- **元数据类型：** bool
+- **关联项：** [Bitflags](../Bitflags/Bitflags.md)
+- **常用程度：** ★★
+
+指定在编辑器里的枚举值直接就是位标记的最终值，而不是标记位。但是注意在C++里的定义是一样的形式：
+
+```cpp
+UENUM(BlueprintType, meta = (Bitflags, UseEnumValuesAsMaskValuesInEditor = "true"))
+enum class EMotionExtractor_MotionType : uint8
+{
+	None				= 0 UMETA(Hidden),
+	Translation			= 1 << 0,
+	Rotation			= 1 << 1,
+	Scale				= 1 << 2,
+	TranslationSpeed	= 1 << 3,
+	RotationSpeed		= 1 << 4,
+};
+
+UENUM(meta = (Bitflags))
+enum class EPCGChangeType : uint8
+{
+	None = 0,
+	Cosmetic = 1 << 0,
+	Settings = 1 << 1,
+	Input = 1 << 2,
+	Edge = 1 << 3,
+	Node = 1 << 4,
+	Structural = 1 << 5
+};
+```
+
+## 测试的代码：
+
+```cpp
+UENUM(BlueprintType,Meta = (Bitflags))
+enum class EMyEnum_BitFlags:uint8
+{
+	First,//0
+	Second,//1
+	Third,//2
+};
+
+UENUM(BlueprintType, meta = (Bitflags, UseEnumValuesAsMaskValuesInEditor = "true"))
+enum class EMyEnum_BitFlagsInEditor:uint8
+{
+	First,//0
+	Second,//1
+	Third,//2
+};
+```
+
+## 测试的蓝图1：
+
+![Untitled_a](Untitled_a.png)
+
+## 测试的蓝图2：
+
+![Untitled_b](Untitled_b.png)
+
+因此可以看出前者是1<<2+1<<2，而后者是1|2，因此后者是直接把枚举值作为已经位移后的值