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diff --git a/dep/include/g3dlite/G3D/Box2D.h b/dep/include/g3dlite/G3D/Box2D.h
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+++ b/dep/include/g3dlite/G3D/Box2D.h
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+/**
+  @file Box2D.h
+ 
+  @maintainer Morgan McGuire, http://graphics.cs.williams.edu
+ 
+  @created 2001-06-02
+  @edited  2008-12-27
+
+  Copyright 2000-2009, Morgan McGuire.
+  All rights reserved.
+ */
+
+#ifndef G3D_Box2D_h
+#define G3D_Box2D_h
+
+#include "G3D/platform.h"
+#include "G3D/Vector2.h"
+
+namespace G3D {
+
+class CoordinateFrame;
+typedef class CoordinateFrame CFrame;
+class Rect2D;
+typedef class Rect2D AABox2D;
+
+/**
+   2D oriented box
+   @cite http://www.flipcode.com/archives/2D_OBB_Intersection.shtml
+ */
+class Box2D {
+private:
+    /** Corners of the box, where 0 is the lower left. */
+    Vector2         m_corner[4];
+
+    /** Two edges of the box extended away from corner[0], with length
+        = 1 / extentSquared */
+    Vector2         m_axisin[2];
+
+    /** Two edges of the box extended away from corner[0], with unit length */
+    Vector2         m_axis[2];
+
+    /** Centroid of the box */
+    Vector2         m_center;
+
+    /** origin[a] = m_corner[0].dot(m_axisin[a]); */
+    float           origin[2];
+
+    /** Surface area */
+    float           m_area;
+
+    Vector2         m_extent;
+
+    /** Returns true if other overlaps one dimension of this. */
+    bool overlaps1Way(const Box2D& other) const;
+
+
+    /** Updates the axes after the m_corners move.  Assumes the
+        m_corners actually form a rectangle. */
+    void computeAxes();
+
+public:
+
+    /** 
+        @param center World-space center
+        @param w Width along object-space x-axis
+        @param h Height along object-space y-axis
+        @param angle Counter-clockwise angle from object-space x-axis in radians
+     */
+    Box2D(const Vector2& center = Vector2(0, 0), float w = 0, float h = 0, float angle = 0);
+
+    Box2D(const AABox2D& b);
+
+    Box2D(const Vector2& min, const Vector2& max);
+
+    /** Transform @a b by @a frame, discarding the Z components, and
+        compute the new box.*/
+    Box2D(const CFrame& frame, Box2D& b);
+    
+    inline bool contains(const Vector2& v) const {
+        // Take to object space:
+        const Vector2& p = v - m_center;
+        float x = p.dot(m_axisin[0]);
+        float y = p.dot(m_axisin[1]);
+
+        // Must be within extent/2 on both axes in object space
+        return (abs(x) <= 0.5f) && (abs(y) <= 0.5f);        
+    }
+
+    /** @brief Distance from corner(0) to the next corner along the box's local axis a. */
+    inline const Vector2& extent() const {
+        return m_extent;
+    }
+
+    /** @brief Unit length vector along axis @a a */
+    inline const Vector2& axis(int a) const {
+        debugAssert(a == 0 || a == 1);
+        return m_axis[a];
+    }
+
+    /** @brief Surface area */
+    inline float area() const {
+        return m_area;
+    }
+
+    inline const Vector2& corner(int i) const {
+        debugAssert(i >=0 && i <= 3);
+        return m_corner[i];
+    }
+
+    inline const Vector2& center() const {
+        return m_center;
+    }
+
+    /** Returns true if the intersection of the boxes is non-empty. */
+    inline bool overlaps(const Box2D& other) const {
+        return overlaps1Way(other) && other.overlaps1Way(*this);
+    }
+};
+
+} // G3D
+#endif