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diff --git a/agg/inc/agg_ellipse_bresenham.h b/agg/inc/agg_ellipse_bresenham.h
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+//----------------------------------------------------------------------------
+// Anti-Grain Geometry - Version 2.3
+// Copyright (C) 2002-2005 Maxim Shemanarev (http://www.antigrain.com)
+//
+// Permission to copy, use, modify, sell and distribute this software
+// is granted provided this copyright notice appears in all copies.
+// This software is provided "as is" without express or implied
+// warranty, and with no claim as to its suitability for any purpose.
+//
+//----------------------------------------------------------------------------
+// Contact: mcseem@antigrain.com
+//          mcseemagg@yahoo.com
+//          http://www.antigrain.com
+//----------------------------------------------------------------------------
+//
+// Simple Bresenham interpolator for ellipsees
+//
+//----------------------------------------------------------------------------
+
+#ifndef AGG_ELLIPSE_BRESENHAM_INCLUDED
+#define AGG_ELLIPSE_BRESENHAM_INCLUDED
+
+
+#include "agg_basics.h"
+
+
+namespace agg
+{
+
+    //------------------------------------------ellipse_bresenham_interpolator
+    class ellipse_bresenham_interpolator
+    {
+    public:
+        ellipse_bresenham_interpolator(int rx, int ry) :
+            m_rx2(rx * rx),
+            m_ry2(ry * ry),
+            m_two_rx2(m_rx2 << 1),
+            m_two_ry2(m_ry2 << 1),
+            m_dx(0),
+            m_dy(0),
+            m_inc_x(0),
+            m_inc_y(-ry * m_two_rx2),
+            m_cur_f(0)
+        {}
+
+        int dx() const { return m_dx; }
+        int dy() const { return m_dy; }
+
+        void operator++ ()
+        {
+            int  mx, my, mxy, min_m;
+            int  fx, fy, fxy;
+
+            mx = fx = m_cur_f + m_inc_x + m_ry2;
+            if(mx < 0) mx = -mx;
+
+            my = fy = m_cur_f + m_inc_y + m_rx2;
+            if(my < 0) my = -my;
+
+            mxy = fxy = m_cur_f + m_inc_x + m_ry2 + m_inc_y + m_rx2;
+            if(mxy < 0) mxy = -mxy;
+
+            min_m = mx;
+            bool flag = true;
+
+            if(min_m > my)
+            {
+                min_m = my;
+                flag = false;
+            }
+
+            m_dx = m_dy = 0;
+
+            if(min_m > mxy)
+            {
+                m_inc_x += m_two_ry2;
+                m_inc_y += m_two_rx2;
+                m_cur_f = fxy;
+                m_dx = 1;
+                m_dy = 1;
+                return;
+            }
+
+            if(flag)
+            {
+                m_inc_x += m_two_ry2;
+                m_cur_f = fx;
+                m_dx = 1;
+                return;
+            }
+
+            m_inc_y += m_two_rx2;
+            m_cur_f = fy;
+            m_dy = 1;
+        }
+
+    private:
+        int m_rx2;
+        int m_ry2;
+        int m_two_rx2;
+        int m_two_ry2;
+        int m_dx;
+        int m_dy;
+        int m_inc_x;
+        int m_inc_y;
+        int m_cur_f;
+
+    };
+
+}
+
+#endif
+