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diff --git a/indra/llmath/llline.h b/indra/llmath/llline.h
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+// llline.h
+/**
+ * @file llline.cpp
+ * @author Andrew Meadows
+ * @brief Simple line for computing nearest approach between two infinite lines
+ *
+ * Copyright (c) 2006-$CurrentYear$, Linden Research, Inc.
+ * $License$
+ */
+
+#ifndef LL_LINE_H
+#define LL_LINE_H
+
+#include <iostream>
+#include "stdtypes.h"
+#include "v3math.h"
+
+const F32 DEFAULT_INTERSECTION_ERROR = 0.000001f;
+
+class LLLine
+{
+public:
+	LLLine();
+	LLLine( const LLVector3& first_point, const LLVector3& second_point );
+	virtual ~LLLine() {};
+
+	void setPointDirection( const LLVector3& first_point, const LLVector3& second_point );
+	void setPoints( const LLVector3& first_point, const LLVector3& second_point );
+
+	bool intersects( const LLVector3& point, F32 radius = DEFAULT_INTERSECTION_ERROR ) const;
+
+	// returns the point on this line that is closest to some_point
+	LLVector3 nearestApproach( const LLVector3& some_point ) const;
+
+	// returns the point on this line that is closest to other_line
+	LLVector3 nearestApproach( const LLLine& other_line ) const;
+
+	friend std::ostream& operator<<( std::ostream& output_stream, const LLLine& line );
+
+	// returns 'true' if this line intersects the plane
+	// on success stores the intersection point in 'result'
+	bool intersectsPlane( LLVector3& result, const LLLine& plane ) const;
+
+	// returns 'true' if planes intersect, and stores the result 
+	// the second and third arguments are treated as planes
+	// where mPoint is on the plane and mDirection is the normal
+	// result.mPoint will be the intersection line's closest approach 
+	// to first_plane.mPoint
+	static bool getIntersectionBetweenTwoPlanes( LLLine& result, const LLLine& first_plane, const LLLine& second_plane );
+
+	const LLVector3& getPoint() const { return mPoint; }
+	const LLVector3& getDirection() const { return mDirection; }
+
+protected:
+	// these are protected because some code assumes that the normal is 
+	// always correct and properly normalized.
+	LLVector3 mPoint;
+	LLVector3 mDirection;
+};
+
+
+#endif