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diff --git a/dep/include/g3dlite/G3D/Plane.h b/dep/include/g3dlite/G3D/Plane.h
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+/**
+ @file Plane.h
+
+ Plane class
+
+ @maintainer Morgan McGuire, matrix@graphics3d.com
+
+ @created 2001-06-02
+ @edited  2004-07-18
+*/
+
+#ifndef G3D_PLANE_H
+#define G3D_PLANE_H
+
+#include "G3D/platform.h"
+#include "G3D/Vector3.h"
+#include "G3D/Vector4.h"
+
+namespace G3D {
+
+/**
+ An infinite 2D plane in 3D space.
+ */
+class Plane {
+private:
+
+    /** normal.Dot(x,y,z) = distance */
+    Vector3						_normal;
+    float						_distance;
+
+    /**
+     Assumes the normal has unit length.
+     */
+    Plane(const Vector3& n, float d) : _normal(n), _distance(d) {
+    }
+
+public:
+
+    Plane() : _normal(Vector3::unitY()), _distance(0) {
+    }
+
+    /**
+     Constructs a plane from three points.
+     */
+    Plane(
+        const Vector3&      point0,
+        const Vector3&      point1,
+        const Vector3&      point2);
+
+    /**
+     Constructs a plane from three points, where at most two are
+     at infinity (w = 0, not xyz = inf).
+     */
+    Plane(
+        Vector4             point0,
+        Vector4             point1,
+        Vector4             point2);
+
+    /**
+     The normal will be unitized.
+     */
+    Plane(
+        const Vector3&      __normal,
+        const Vector3&      point);
+
+    static Plane fromEquation(float a, float b, float c, float d);
+
+    virtual ~Plane() {}
+
+    /**
+     Returns true if point is on the side the normal points to or 
+     is in the plane.
+     */
+    inline bool halfSpaceContains(Vector3 point) const {
+        // Clamp to a finite range for testing
+        point = point.clamp(Vector3::minFinite(), Vector3::maxFinite());
+
+        // We can get away with putting values *at* the limits of the float32 range into
+        // a dot product, since the dot product is carried out on float64.
+        return _normal.dot(point) >= _distance;
+    }
+
+    /**
+     Returns true if point is on the side the normal points to or 
+     is in the plane.
+     */
+    inline bool halfSpaceContains(const Vector4& point) const {
+        if (point.w == 0) {
+            return _normal.dot(point.xyz()) > 0;
+        } else {
+            return halfSpaceContains(point.xyz() / point.w);
+        }
+    }
+
+    /**
+     Returns true if point is on the side the normal points to or 
+     is in the plane.  Only call on finite points.  Faster than halfSpaceContains.
+     */
+    inline bool halfSpaceContainsFinite(const Vector3& point) const {
+        debugAssert(point.isFinite());
+        return _normal.dot(point) >= _distance;
+    }
+
+    /**
+     Returns true if the point is nearly in the plane.
+     */
+    inline bool fuzzyContains(const Vector3 &point) const {
+        return fuzzyEq(point.dot(_normal), _distance);
+    }
+
+	inline const Vector3& normal() const {
+		return _normal;
+	}
+
+    /**
+      Returns distance from point to plane. Distance is negative if point is behind (not in plane in direction opposite normal) the plane.
+    */
+    inline float distance(const Vector3& x) const {
+        return (_normal.dot(x) - _distance);
+    }
+
+    inline Vector3 closestPoint(const Vector3& x) const {
+        return x + (_normal * (-distance(x)));
+    }
+
+    /** Returns normal * distance from origin */
+    Vector3 center() const {
+        return _normal * _distance;
+    }
+
+    /**
+     Inverts the facing direction of the plane so the new normal
+     is the inverse of the old normal.
+     */
+    void flip();
+
+    /**
+      Returns the equation in the form:
+
+      <CODE>normal.Dot(Vector3(<I>x</I>, <I>y</I>, <I>z</I>)) + d = 0</CODE>
+     */
+    void getEquation(Vector3 &normal, double& d) const;
+    void getEquation(Vector3 &normal, float& d) const;
+
+    /**
+      ax + by + cz + d = 0
+     */
+    void getEquation(double& a, double& b, double& c, double& d) const;
+    void getEquation(float& a, float& b, float& c, float& d) const;
+
+    std::string toString() const;
+};
+
+} // namespace
+
+#endif