diff -r 7b44eea654d0 -r 7cd965d2257f lemon/bits/bezier.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lemon/bits/bezier.h	Thu Apr 03 11:10:49 2008 +0100
@@ -0,0 +1,176 @@
+/* -*- C++ -*-
+ *
+ * This file is a part of LEMON, a generic C++ optimization library
+ *
+ * Copyright (C) 2003-2008
+ * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
+ * (Egervary Research Group on Combinatorial Optimization, EGRES).
+ *
+ * Permission to use, modify and distribute this software is granted
+ * provided that this copyright notice appears in all copies. For
+ * precise terms see the accompanying LICENSE file.
+ *
+ * This software is provided "AS IS" with no warranty of any kind,
+ * express or implied, and with no claim as to its suitability for any
+ * purpose.
+ *
+ */
+
+#ifndef LEMON_BEZIER_H
+#define LEMON_BEZIER_H
+
+///\ingroup misc
+///\file
+///\brief Classes to compute with Bezier curves.
+///
+///Up to now this file is used internally by \ref graph_to_eps.h
+///
+///\author Alpar Juttner
+
+#include<lemon/dim2.h>
+
+namespace lemon {
+  namespace dim2 {
+
+class BezierBase {
+public:
+  typedef Point<double> Point;
+protected:
+  static Point conv(Point x,Point y,double t) {return (1-t)*x+t*y;}
+};
+
+class Bezier1 : public BezierBase
+{
+public:
+  Point p1,p2;
+
+  Bezier1() {}
+  Bezier1(Point _p1, Point _p2) :p1(_p1), p2(_p2) {}
+  
+  Point operator()(double t) const
+  {
+    //    return conv(conv(p1,p2,t),conv(p2,p3,t),t);
+    return conv(p1,p2,t);
+  }
+  Bezier1 before(double t) const
+  {
+    return Bezier1(p1,conv(p1,p2,t));
+  }
+  
+  Bezier1 after(double t) const
+  {
+    return Bezier1(conv(p1,p2,t),p2);
+  }
+
+  Bezier1 revert() const { return Bezier1(p2,p1);}
+  Bezier1 operator()(double a,double b) const { return before(b).after(a/b); }
+  Point grad() const { return p2-p1; }
+  Point norm() const { return rot90(p2-p1); }
+  Point grad(double) const { return grad(); }
+  Point norm(double t) const { return rot90(grad(t)); }
+};
+
+class Bezier2 : public BezierBase
+{
+public:
+  Point p1,p2,p3;
+
+  Bezier2() {}
+  Bezier2(Point _p1, Point _p2, Point _p3) :p1(_p1), p2(_p2), p3(_p3) {}
+  Bezier2(const Bezier1 &b) : p1(b.p1), p2(conv(b.p1,b.p2,.5)), p3(b.p2) {}
+  Point operator()(double t) const
+  {
+    //    return conv(conv(p1,p2,t),conv(p2,p3,t),t);
+    return ((1-t)*(1-t))*p1+(2*(1-t)*t)*p2+(t*t)*p3;
+  }
+  Bezier2 before(double t) const
+  {
+    Point q(conv(p1,p2,t));
+    Point r(conv(p2,p3,t));
+    return Bezier2(p1,q,conv(q,r,t));
+  }
+  
+  Bezier2 after(double t) const
+  {
+    Point q(conv(p1,p2,t));
+    Point r(conv(p2,p3,t));
+    return Bezier2(conv(q,r,t),r,p3);
+  }
+  Bezier2 revert() const { return Bezier2(p3,p2,p1);}
+  Bezier2 operator()(double a,double b) const { return before(b).after(a/b); }
+  Bezier1 grad() const { return Bezier1(2.0*(p2-p1),2.0*(p3-p2)); }
+  Bezier1 norm() const { return Bezier1(2.0*rot90(p2-p1),2.0*rot90(p3-p2)); }
+  Point grad(double t) const { return grad()(t); }
+  Point norm(double t) const { return rot90(grad(t)); }
+};
+
+class Bezier3 : public BezierBase
+{
+public:
+  Point p1,p2,p3,p4;
+
+  Bezier3() {}
+  Bezier3(Point _p1, Point _p2, Point _p3, Point _p4)
+    : p1(_p1), p2(_p2), p3(_p3), p4(_p4) {}
+  Bezier3(const Bezier1 &b) : p1(b.p1), p2(conv(b.p1,b.p2,1.0/3.0)), 
+			      p3(conv(b.p1,b.p2,2.0/3.0)), p4(b.p2) {}
+  Bezier3(const Bezier2 &b) : p1(b.p1), p2(conv(b.p1,b.p2,2.0/3.0)),
+			      p3(conv(b.p2,b.p3,1.0/3.0)), p4(b.p3) {}
+  
+  Point operator()(double t) const 
+    {
+      //    return Bezier2(conv(p1,p2,t),conv(p2,p3,t),conv(p3,p4,t))(t);
+      return ((1-t)*(1-t)*(1-t))*p1+(3*t*(1-t)*(1-t))*p2+
+	(3*t*t*(1-t))*p3+(t*t*t)*p4;
+    }
+  Bezier3 before(double t) const
+    {
+      Point p(conv(p1,p2,t));
+      Point q(conv(p2,p3,t));
+      Point r(conv(p3,p4,t));
+      Point a(conv(p,q,t));
+      Point b(conv(q,r,t));
+      Point c(conv(a,b,t));
+      return Bezier3(p1,p,a,c);
+    }
+  
+  Bezier3 after(double t) const
+    {
+      Point p(conv(p1,p2,t));
+      Point q(conv(p2,p3,t));
+      Point r(conv(p3,p4,t));
+      Point a(conv(p,q,t));
+      Point b(conv(q,r,t));
+      Point c(conv(a,b,t));
+      return Bezier3(c,b,r,p4);
+    }
+  Bezier3 revert() const { return Bezier3(p4,p3,p2,p1);}
+  Bezier3 operator()(double a,double b) const { return before(b).after(a/b); }
+  Bezier2 grad() const { return Bezier2(3.0*(p2-p1),3.0*(p3-p2),3.0*(p4-p3)); }
+  Bezier2 norm() const { return Bezier2(3.0*rot90(p2-p1),
+				  3.0*rot90(p3-p2),
+				  3.0*rot90(p4-p3)); }
+  Point grad(double t) const { return grad()(t); }
+  Point norm(double t) const { return rot90(grad(t)); }
+
+  template<class R,class F,class S,class D>
+  R recSplit(F &_f,const S &_s,D _d) const 
+  {
+    const Point a=(p1+p2)/2;
+    const Point b=(p2+p3)/2;
+    const Point c=(p3+p4)/2;
+    const Point d=(a+b)/2;
+    const Point e=(b+c)/2;
+    const Point f=(d+e)/2;
+    R f1=_f(Bezier3(p1,a,d,e),_d);
+    R f2=_f(Bezier3(e,d,c,p4),_d);
+    return _s(f1,f2);
+  }
+  
+};
+
+
+} //END OF NAMESPACE dim2
+} //END OF NAMESPACE lemon
+
+#endif // LEMON_BEZIER_H