Unity3d property drawer for automatically making enums flags into mask fields in the inspector.

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Unity3d property drawer for automatically making enums flags into mask fields in the inspector.

Usage: Put the .cs files somewhere in your project. When you have an enum field you want to turn into a mask field in the inspector, add the EnumFlag attribute over the field. Eg:

[EnumFlag]
MyCustomEnum thisEnum;
// This lets you give the field a custom name in the inspector.
[EnumFlag("Custom Inspector Name")]
MyCustomEnum anotherEnum;

My updates:
-Added modification check to better support multi-object editing
-Added support for the better Unity 2017.3 version of the flag property drawer: EditorGUI.EnumFlagsField()
-Added Nicifier formatting on field name for parameter-less attribute
-Removed "static T GetBaseProperty<T>(SerializedProperty prop)", and replaced it
    with the cleaner "Enum targetEnum = (Enum)Enum.ToObject(fieldInfo.FieldType, property.intValue);" line from another fork

The EnumFlagsAtrribute.cs is the same as other forks

EnumFlagAttribute.cs

using UnityEngine;

public class EnumFlagAttribute : PropertyAttribute
{
	public string enumName;

	public EnumFlagAttribute() {}

	public EnumFlagAttribute(string name)
	{
		enumName = name;
	}
}

EnumFlagDrawer.cs

using System;
using System.Reflection;
using UnityEditor;
using UnityEngine;

[CustomPropertyDrawer(typeof(EnumFlagAttribute))]
public class EnumFlagDrawer : PropertyDrawer {
	public override void OnGUI(Rect position, SerializedProperty property, GUIContent label)
	{

		EnumFlagsAttribute flagSettings = (EnumFlagsAttribute)attribute;
		Enum targetEnum = (Enum)Enum.ToObject(fieldInfo.FieldType, property.intValue);

		string propName = flagSettings.enumName;
		if (string.IsNullOrEmpty(propName))
			propName = ObjectNames.NicifyVariableName(property.name);

		EditorGUI.BeginChangeCheck();
		EditorGUI.BeginProperty(position, label, property);
#if UNITY_2017_3_OR_NEWER
		Enum enumNew = EditorGUI.EnumFlagsField(position, propName, targetEnum);
#else
		Enum enumNew = EditorGUI.EnumMaskField(position, propName, targetEnum);
#endif
		if (!property.hasMultipleDifferentValues || EditorGUI.EndChangeCheck())
			property.intValue = (int)Convert.ChangeType(enumNew, targetEnum.GetType());

		EditorGUI.EndProperty();
	}
}

thanks a lot
here is one that does not need attributes

using System;
using UnityEditor;
using UnityEngine;
namespace UnityEngine.Tilemaps
{
	[Flags]
	public enum TileOrientation
	{
		None = 0,
		FlipX = 1,
		FlipY = (1 << 1),
		Rot90 = (1 << 2),
	}
#if UNITY_EDITOR
	[CustomPropertyDrawer(typeof(TileOrientation))]
	public class TileOrientationDrawer : PropertyDrawer
	{
		public override void OnGUI(Rect position, SerializedProperty property, GUIContent label)
		{
			label = EditorGUI.BeginProperty(position, label, property);
			property.intValue = (int)(TileOrientation)EditorGUI.EnumFlagsField(position, label, (TileOrientation)property.intValue);
			EditorGUI.EndProperty();
		}
	}
#endif
}