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Source/Engine/CSG/Polygon.h

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+#pragma once
+
+#include "Engine/Core/Math/AABB.h"
+
+namespace CSG
+{
+    enum PolygonSplitResult
+    {
+        /// <summary>
+        /// Polygon is completely inside half-space defined by plane
+        /// </summary>
+        CompletelyInside,
+
+        /// <summary>
+        /// Polygon is completely outside half-space defined by plane
+        /// </summary>
+        CompletelyOutside,
+
+        /// <summary>
+        /// Polygon has been split into two parts by plane
+        /// </summary>
+        Split,
+
+        /// <summary>
+        /// Polygon is aligned with cutting plane and the polygons' normal points in the same direction
+        /// </summary>
+        PlaneAligned,
+
+        /// <summary>
+        /// Polygon is aligned with cutting plane and the polygons' normal points in the opposite direction
+        /// </summary>
+        PlaneOppositeAligned
+    };
+
+    /// <summary>
+    /// Polygon structure
+    /// </summary>
+    struct Polygon
+    {
+        int32 FirstEdgeIndex;
+        int32 SurfaceIndex;
+        bool Visible;
+        bool Inverted;
+        AABB Bounds;
+
+        Polygon()
+        {
+            // TODO: remove this constructor to boost performance??
+            FirstEdgeIndex = INVALID_INDEX;
+            SurfaceIndex = INVALID_INDEX;
+            Inverted = false;
+            Visible = false;
+            Bounds = AABB();
+        }
+    };
+};