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diff --git a/ETL/ETL/_bspline.h b/ETL/ETL/_bspline.h
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+/*! ========================================================================
+** Extended Template and Library
+** B-Spline Class Implementation
+** $Id$
+**
+** Copyright (c) 2002 Robert B. Quattlebaum Jr.
+**
+** This package is free software; you can redistribute it and/or
+** modify it under the terms of the GNU General Public License as
+** published by the Free Software Foundation; either version 2 of
+** the License, or (at your option) any later version.
+**
+** This package is distributed in the hope that it will be useful,
+** but WITHOUT ANY WARRANTY; without even the implied warranty of
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+** General Public License for more details.
+**
+** === N O T E S ===========================================================
+**
+** This is an internal header file, included by other ETL headers.
+** You should not attempt to use it directly.
+**
+** ========================================================================= */
+
+/* === S T A R T =========================================================== */
+
+#ifndef __ETL__BSPLINE_H
+#define __ETL__BSPLINE_H
+
+/* === H E A D E R S ======================================================= */
+
+#include <vector>
+#include <functional>
+#include "_curve_func.h"
+
+/* === M A C R O S ========================================================= */
+
+/* === T Y P E D E F S ===================================================== */
+
+/* === C L A S S E S & S T R U C T S ======================================= */
+
+_ETL_BEGIN_NAMESPACE
+
+template <class T, class K=float, class C=affine_combo<T,K>, class D=distance_func<T> >
+class bspline : public std::unary_function<K,T>
+{
+public:
+	typedef T value_type;
+	typedef K knot_type;
+	typedef std::vector<knot_type>	knot_container;
+	typedef std::vector<value_type>	cpoint_container;
+	typedef typename knot_container::iterator knot_iterator;
+	typedef typename cpoint_container::iterator cpoint_iterator;
+
+	typedef C affine_func_type;
+	typedef D distance_func_type;
+
+protected:
+	affine_func_type affine_func;
+	distance_func_type distance_func;
+
+private:
+	int m;
+	knot_container _knots;
+	cpoint_container _cpoints;
+	bool _loop;
+
+public:
+	bspline():m(2),_loop(false) {  }
+
+	int get_m()const { return m-1; };
+	int set_m(int new_m) { m=new_m+1; return m-1; };
+
+	bool set_loop(bool x) { _loop=x; reset_knots(); return _loop; }
+
+	knot_container & knots() { return _knots; };
+	cpoint_container & cpoints() { return _cpoints; };
+
+	const knot_container & knots()const { return _knots; };
+	const cpoint_container & cpoints()const { return _cpoints; };
+
+	void reset_knots()
+	{
+		int i;
+
+		if(!_loop)
+		{
+			_knots.clear();
+			if(!_cpoints.size())
+				return;
+			while(m>(signed)_cpoints.size())
+				m--;
+			for(i=0;i<m;i++)
+				*_knots.insert(_knots.end())=0;
+			for(i=1;i<(signed)_cpoints.size()-m+1;i++)
+				*_knots.insert(_knots.end())=i;
+			for(i=0;i<m;i++)
+				*_knots.insert(_knots.end())=_cpoints.size()-m+1;
+		}
+		else
+		{
+			_knots.clear();
+			if(!_cpoints.size())
+				return;
+			while(m>(signed)_cpoints.size())
+				m--;
+			for(i=0;i<=(signed)_cpoints.size()-m+1;i++)
+				*_knots.insert(_knots.end())=i;
+		}
+	}
+
+	int calc_curve_segment(knot_type t)const
+	{
+		int k;
+		if(t<0)
+			t=0;
+		if(t>=_knots.back())
+			t=_knots.back()-0.0001;
+		for(k=0;_knots[k]>t || _knots[k+1]<=t;k++)
+		  ;
+
+		return k;
+	}
+
+	knot_container get_segment_knots(int i)const
+	{
+		if(i+1<m)
+		{
+			knot_container ret(_knots.begin(),_knots.begin()+i+m+1);
+
+			return ret;
+		}
+		if(i+1>=(signed)_knots.size())
+		{
+			knot_container ret(_knots.begin()+i-m+1,_knots.end());
+			return ret;
+		}
+		return knot_container(_knots.begin()+i-m+1,	_knots.begin()+i+m);
+	}
+
+	cpoint_container get_segment_cpoints(int i)const
+	{
+		if(i+1<m)
+		{
+			return cpoint_container();
+		}
+		if(i+1>=(signed)_knots.size())
+		{
+			return cpoint_container();
+		}
+		return cpoint_container(_cpoints.begin()+i-m+1,	_cpoints.begin()+i+1);
+	}
+
+	cpoint_container calc_shell(knot_type t, int level)const
+	{
+		int
+			i=calc_curve_segment(t),
+			j,k;
+
+		knot_container u=get_segment_knots(i);
+
+		cpoint_container d=get_segment_cpoints(i);
+
+		if(!d.size())
+			return cpoint_container();
+
+		for(j=0;d.size()>1 && j<level;d.pop_back(),j++)
+		{
+			for(k=0;k<d.size()-1;k++)
+			{
+				d[k]=affine_func(d[k],d[k+1],((t-u[j+k+1])/(u[m+k]-u[j+k+1])));
+			}
+		}
+		return d;
+	}
+
+	value_type operator()(knot_type t)const
+	{
+		return get_curve_val(calc_curve_segment(t),t);
+	}
+
+	value_type get_curve_val(int i,knot_type t)const
+	{
+		int
+			j,k;
+
+		knot_container u=get_segment_knots(i);
+
+		cpoint_container d=get_segment_cpoints(i);
+
+		if(!d.size())
+			return value_type();
+
+		for(j=0;d.size()>1;d.pop_back(),j++)
+		{
+			for(k=0;k<(signed)d.size()-1;k++)
+			{
+				d[k]=affine_func(d[k],d[k+1],((t-u[j+k+1])/(u[m+k]-u[j+k+1])));
+			}
+		}
+		return d.front();
+	}
+
+	cpoint_iterator find_closest_cpoint(const value_type &point, typename distance_func_type::result_type max)
+	{
+		cpoint_iterator i=_cpoints.begin();
+		cpoint_iterator ret=i;
+		typename distance_func_type::result_type dist=distance_func(point,_cpoints[0]);
+
+		// The distance function returns "cooked" (ie: squared)
+		// distances, so we need to cook our max distance for
+		// the comparison to work correctly.
+		max=distance_func.cook(max);
+
+		for(++i;i<_cpoints.end();i++)
+		{
+			typename distance_func_type::result_type thisdist=distance_func(point,*i);
+
+			if(thisdist<dist)
+			{
+				dist=thisdist;
+				ret=i;
+			}
+		}
+		if(dist<max)
+			return ret;
+		return _cpoints.end();
+	}
+};
+
+_ETL_END_NAMESPACE
+
+/* -- F U N C T I O N S ----------------------------------------------------- */
+
+/* -- E N D ----------------------------------------------------------------- */
+
+#endif