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Source/Engine/Core/Config/PlatformSettingsBase.h

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+#pragma once
+
+#include "Engine/Core/Config/Settings.h"
+#include "Engine/Serialization/Serialization.h"
+
+/// <summary>
+/// Specifies the display mode of a game window.
+/// </summary>
+API_ENUM() enum class GameWindowMode
+{
+    /// <summary>
+    /// The window has borders and does not take up the full screen.
+    /// </summary>
+    Windowed = 0,
+
+    /// <summary>
+    /// The window takes up the full screen exclusively.
+    /// </summary>
+    Fullscreen = 1,
+
+    /// <summary>
+    /// The window behaves like in Windowed mode but has no borders.
+    /// </summary>
+    Borderless = 2,
+
+    /// <summary>
+    /// Same as in Borderless, but is of the size of the screen.
+    /// </summary>
+    FullscreenBorderless = 3
+};