--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,23 @@
+2009-11-10  Shai Ayal  <shaiay@users.sourceforge.net>
+
+	* gl2ps-renderer.cc, gl2ps-renderer.h, gl2ps.c, gl2ps.h:
+	New files.  PostScript backend based on opengl_renderer and gl2ps.
+	* Makefile.am (octinclude_HEADERS): Add gl2ps.h to the list.
+	(DIST_SRC): Add gl2ps.c to the list.
+	* gl-render.cc (opengl_renderer::render_text): Rename from
+	opengl_renderer::draw_text.
+	(opengl_renderer::draw_figure, opengl_renderer::draw_axes,
+	opengl_renderer::draw_line, opengl_renderer::draw_surface,
+	opengl_renderer::draw_patch, opengl_renderer::draw_hggroup,
+	opengl_renderer::draw_text, opengl_renderer::draw_image):
+	Rename from overloaded opengl_renderer::draw.
+	* gl-render.h: Fix decls.
+
+	* DLD-FUNCTIONS/fltk_backend.cc	(OpenGL_fltk::print): New function.
+	(OpenGL_fltk::print_filename): New data member.
+	(OpenGL_fltk::draw): Add support for printing.
+	(fltk_backend::print_figure): Call figure_manager::print.
+
 2009-11-10  John W. Eaton  <jwe@octave.org>
 
 	* file-io.cc (Fferror): Update doc string.

--- a/src/DLD-FUNCTIONS/fltk_backend.cc
+++ b/src/DLD-FUNCTIONS/fltk_backend.cc
@@ -60,6 +60,7 @@
 #include "defun-dld.h"
 #include "error.h"
 #include "gl-render.h"
+#include "gl2ps-renderer.h"
 #include "graphics.h"
 #include "parse.h"
 #include "variables.h"
@@ -83,7 +84,8 @@
 {
 public:
   OpenGL_fltk (int xx, int yy, int ww, int hh, double num)
-    : Fl_Gl_Window (xx, yy, ww, hh, 0), number (num), in_zoom (false)
+    : Fl_Gl_Window (xx, yy, ww, hh, 0), number (num), in_zoom (false),
+      print_filename ("")
   {
     // ask for double buffering and a depth buffer
     mode (FL_DEPTH | FL_DOUBLE);
@@ -92,18 +94,29 @@
   ~OpenGL_fltk (void) { }
 
   void zoom (bool z) 
-  {in_zoom = z; if (!in_zoom) hide_overlay ();}
+  {
+    in_zoom = z;
+    if (! in_zoom)
+      hide_overlay ();
+  }
+
   bool zoom (void) { return in_zoom; }
   void set_zoom_box (const Matrix& zb) { zoom_box = zb; }
+  
+  void print (const std::string& filename)
+  {
+    print_filename  = filename;
+  }
 
 private:
   double number;
   opengl_renderer renderer;
   bool in_zoom;
-
   // (x1,y1,x2,y2)
   Matrix zoom_box;
 
+  std::string print_filename;
+
   void setup_viewport (int _w, int _h)
   {
     glMatrixMode (GL_PROJECTION);
@@ -113,16 +126,26 @@
 
   void draw (void)
   {
-    if (!valid ())
+    if (! valid ())
       {
 	valid (1);
 	setup_viewport (w (), h ());
       }
 
-    renderer.draw (gh_manager::lookup (number));
+    if (! print_filename.empty ())
+      {
+	opengl_renderer *rend = new glps_renderer (print_filename);
+	rend->draw (gh_manager::lookup (number));
+	print_filename = "";
+	delete rend;
+      }
+    else
+      {
+	renderer.draw (gh_manager::lookup (number));
+      }
   }
 
-  void resize (int _x,int _y,int _w,int _h)
+  void resize (int _x, int _y, int _w, int _h)
   {
     Fl_Gl_Window::resize (_x, _y, _w, _h);
     setup_viewport (_w, _h);
@@ -131,12 +154,12 @@
 
   void draw_overlay (void)
   {
-    if (!in_zoom)
+    if (! in_zoom)
       return;
 
-    if (!valid())
+    if (! valid ())
       {
-	valid(1);
+	valid (1);
 	setup_viewport (w (), h ());
       }
 
@@ -269,6 +292,11 @@
   // FIXME -- this could change
   double number (void) { return fp.get___myhandle__ ().value (); }
 
+  void print (const std::string& fname)
+  {
+    canvas->print (fname);
+  }
+
   void mark_modified (void)
   {
     damage (FL_DAMAGE_ALL);
@@ -654,6 +682,12 @@
     return get_size (hnd2idx (gh));
   }
 
+  static void print (const graphics_handle& gh , const std::string& filename)
+  {
+    if (instance_ok ())
+      instance->do_print (hnd2idx(gh), filename);
+  }
+
 private:
 
   static figure_manager *instance;
@@ -727,6 +761,15 @@
     return sz;
   }
 
+  void do_print (int idx, const std::string& filename)
+  {
+    wm_iterator win;
+    if ((win = windows.find (idx)) != windows.end ())
+      {
+	win->second->print (filename);
+      }
+  }
+
   // FIXME -- default size should be configurable.
   void default_size (int& x, int& y, int& w, int& h)
   {
@@ -873,10 +916,13 @@
     __fltk_redraw__ ();
   }
 
-  void print_figure (const graphics_object& /*go*/,
-		     const std::string& /*term*/,
-		     const std::string& /*file*/, bool /*mono*/,
-		     const std::string& /*debug_file*/) const { }
+  void print_figure (const graphics_object& go,
+		     const std::string& term,
+		     const std::string& file, bool mono,
+		     const std::string& debug_file) const 
+  { 
+    figure_manager::print (go.get_handle (), file);
+  }
 
   Matrix get_canvas_size (const graphics_handle& fh) const
   {

--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -206,6 +206,8 @@
   error.h \
   file-io.h \
   gl-render.h \
+  gl2ps.h \
+  gl2ps-renderer.h \
   graphics.h \
   graphics-props.cc \
   gripes.h \
@@ -368,6 +370,8 @@
   error.cc \
   file-io.cc \
   gl-render.cc \
+  gl2ps.c \
+  gl2ps-renderer.cc \
   graphics.cc \
   gripes.cc \
   help.cc \

--- a/src/gl-render.cc
+++ b/src/gl-render.cc
@@ -535,32 +535,32 @@
 {
   if (! go.valid_object ())
     return;
-
+  
   const base_properties& props = go.get_properties ();
 
   if (go.isa ("figure"))
-    draw (dynamic_cast<const figure::properties&> (props));
+    draw_figure (dynamic_cast<const figure::properties&> (props));
   else if (go.isa ("axes"))
-    draw (dynamic_cast<const axes::properties&> (props));
+    draw_axes (dynamic_cast<const axes::properties&> (props));
   else if (go.isa ("line"))
-    draw (dynamic_cast<const line::properties&> (props));
+    draw_line (dynamic_cast<const line::properties&> (props));
   else if (go.isa ("surface"))
-    draw (dynamic_cast<const surface::properties&> (props));
+    draw_surface (dynamic_cast<const surface::properties&> (props));
   else if (go.isa ("patch"))
-    draw (dynamic_cast<const patch::properties&> (props));
+    draw_patch (dynamic_cast<const patch::properties&> (props));
   else if (go.isa ("hggroup"))
-    draw (dynamic_cast<const hggroup::properties&> (props));
+    draw_hggroup (dynamic_cast<const hggroup::properties&> (props));
   else if (go.isa ("text"))
-    draw (dynamic_cast<const text::properties&> (props));
+    draw_text (dynamic_cast<const text::properties&> (props));
   else if (go.isa ("image"))
-    draw (dynamic_cast<const image::properties&> (props));
+    draw_image (dynamic_cast<const image::properties&> (props));
   else
     warning ("opengl_renderer: cannot render object of type `%s'",
 	     props.graphics_object_name ().c_str ());
 }
 
 void
-opengl_renderer::draw (const figure::properties& props)
+opengl_renderer::draw_figure (const figure::properties& props)
 {
   backend = props.get_backend ();
 
@@ -599,7 +599,7 @@
 }
 
 void
-opengl_renderer::draw (const axes::properties& props)
+opengl_renderer::draw_axes (const axes::properties& props)
 {
   // setup OpenGL transformation
 
@@ -986,7 +986,7 @@
 	    {
 	      // FIXME: as tick text is transparent, shouldn't be
 	      //        drawn after axes object, for correct rendering?
-	      Matrix b = draw_text (xticklabels(i),
+	      Matrix b = render_text (xticklabels(i),
 				    tickpos(i,0), tickpos(i,1), tickpos(i,2),
 				    halign, valign); 
 
@@ -1196,7 +1196,7 @@
 	    {
 	      // FIXME: as tick text is transparent, shouldn't be
 	      //        drawn after axes object, for correct rendering?
-	      Matrix b = draw_text (yticklabels(i),
+	      Matrix b = render_text (yticklabels(i),
 				    tickpos(i,0), tickpos(i,1), tickpos(i,2),
 				    halign, valign); 
 
@@ -1438,7 +1438,7 @@
 	    {
 	      // FIXME: as tick text is transparent, shouldn't be
 	      //        drawn after axes object, for correct rendering?
-	      Matrix b = draw_text (zticklabels(i),
+	      Matrix b = render_text (zticklabels(i),
 				    tickpos(i,0), tickpos(i,1), tickpos(i,2),
 				    halign, valign); 
 
@@ -1679,7 +1679,7 @@
 }
 
 void
-opengl_renderer::draw (const line::properties& props)
+opengl_renderer::draw_line (const line::properties& props)
 {
   Matrix x = xform.xscale (props.get_xdata ().matrix_value ());
   Matrix y = xform.yscale (props.get_ydata ().matrix_value ());
@@ -1799,7 +1799,7 @@
 }
 
 void
-opengl_renderer::draw (const surface::properties& props)
+opengl_renderer::draw_surface (const surface::properties& props)
 {
   const Matrix x = xform.xscale (props.get_xdata ().matrix_value ());
   const Matrix y = xform.yscale (props.get_ydata ().matrix_value ());
@@ -2346,7 +2346,7 @@
 // FIXME: global optimization (rendering, data structures...), there
 // is probably a smarter/faster/less-memory-consuming way to do this.
 void
-opengl_renderer::draw (const patch::properties &props)
+opengl_renderer::draw_patch (const patch::properties &props)
 {
   const Matrix f = props.get_faces ().matrix_value ();
   const Matrix v = xform.scale (props.get_vertices ().matrix_value ());
@@ -2654,13 +2654,13 @@
 }
 
 void
-opengl_renderer::draw (const hggroup::properties &props)
+opengl_renderer::draw_hggroup (const hggroup::properties &props)
 {
   draw (props.get_children ());
 }
 
 void
-opengl_renderer::draw (const text::properties& props)
+opengl_renderer::draw_text (const text::properties& props)
 {
   if (props.get_string ().empty ())
     return;
@@ -2686,13 +2686,13 @@
 
   // FIXME: handle margin and surrounding box
 
-  draw_text (props.get_string (),
+  render_text (props.get_string (),
 	     pos(0), pos(1), pos(2),
 	     halign, valign, props.get_rotation ());
 }
 
 void
-opengl_renderer::draw (const image::properties& props)
+opengl_renderer::draw_image (const image::properties& props)
 {
   octave_value cdata = props.get_cdata ();
   dim_vector dv (cdata.dims ());
@@ -3141,7 +3141,7 @@
 }
 
 Matrix
-opengl_renderer::draw_text (const std::string& txt,
+opengl_renderer::render_text (const std::string& txt,
 			    double x, double y, double z,
 			    int halign, int valign, double rotation)
 {
@@ -3220,7 +3220,7 @@
 
   return bbox;
 #else
-  ::warning ("draw_text: cannot render text, Freetype library not available");
+  ::warning ("render_text: cannot render text, Freetype library not available");
   return Matrix (1, 4, 0.0);
 #endif
 }

--- a/src/gl-render.h
+++ b/src/gl-render.h
@@ -72,14 +72,14 @@
   virtual void set_viewport (int w, int h);
 
 protected:
-  virtual void draw (const figure::properties& props);
-  virtual void draw (const axes::properties& props);
-  virtual void draw (const line::properties& props);
-  virtual void draw (const surface::properties& props);
-  virtual void draw (const patch::properties& props);
-  virtual void draw (const hggroup::properties& props);
-  virtual void draw (const text::properties& props);
-  virtual void draw (const image::properties& props);
+  virtual void draw_figure (const figure::properties& props);
+  virtual void draw_axes (const axes::properties& props);
+  virtual void draw_line (const line::properties& props);
+  virtual void draw_surface (const surface::properties& props);
+  virtual void draw_patch (const patch::properties& props);
+  virtual void draw_hggroup (const hggroup::properties& props);
+  virtual void draw_text (const text::properties& props);
+  virtual void draw_image (const image::properties& props);
 
   virtual void set_color (const Matrix& c);
   virtual void set_polygon_offset (bool on, double offset = 0.0);
@@ -95,7 +95,7 @@
   virtual void draw_marker (double x, double y, double z,
 			    const Matrix& lc, const Matrix& fc);
 
-  virtual Matrix draw_text (const std::string& txt,
+  virtual Matrix render_text (const std::string& txt,
 			    double x, double y, double z,
 			    int halign, int valign, double rotation = 0.0);
 

new file mode 100644
--- /dev/null
+++ b/src/gl2ps-renderer.cc
@@ -0,0 +1,148 @@
+/*
+
+Copyright (C) 2009 Shai Ayal
+
+This file is part of Octave.
+
+Octave 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 3 of the License, or (at your
+option) any later version.
+
+Octave 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.
+
+You should have received a copy of the GNU General Public License
+along with Octave; see the file COPYING.  If not, see
+<http://www.gnu.org/licenses/>.
+
+*/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#if defined (HAVE_OPENGL)
+
+#include <cstdio>
+
+#include "lo-mappers.h"
+#include "oct-locbuf.h"
+
+#include "gl2ps-renderer.h"
+#include "gl2ps.h"
+
+void 
+glps_renderer::draw (const graphics_object& go) 
+{
+  static bool in_draw = false;
+  
+  if (!in_draw) 
+    {
+      in_draw = true;
+
+      FILE *fp = fopen (filename.c_str (), "wb");
+      GLint buffsize = 0, state = GL2PS_OVERFLOW;
+      GLint viewport[4];
+
+      glGetIntegerv (GL_VIEWPORT, viewport);
+
+      while (state == GL2PS_OVERFLOW)
+	{ 
+	  buffsize += 1024*1024;
+	  gl2psBeginPage ("glps_renderer figure", "Octave", viewport,
+			  GL2PS_EPS, GL2PS_BSP_SORT,
+			  (GL2PS_SILENT | GL2PS_SIMPLE_LINE_OFFSET
+			   | GL2PS_NO_BLENDING | GL2PS_OCCLUSION_CULL
+			   | GL2PS_BEST_ROOT), GL_RGBA, 0, NULL, 0, 0, 0,
+			  buffsize, fp, filename.c_str () );
+
+	  opengl_renderer::draw (go);
+	  state = gl2psEndPage ();
+	}
+
+      fclose (fp);
+
+      in_draw = 0;
+    }
+  else
+    opengl_renderer::draw (go); 
+}
+
+Matrix 
+glps_renderer::render_text (const std::string& txt,
+			    double x, double y, double z,
+			    int ha, int va, double rotation)
+{
+  Matrix retval = Matrix (1, 4, 0.0);
+
+  if (txt.empty ())
+    return retval;
+
+  int gl2psa=GL2PS_TEXT_BL;
+  if (ha == 0)
+    {
+      if (va == 0 || va == 3)
+	gl2psa=GL2PS_TEXT_BL;
+      else if (va == 2)
+	gl2psa=GL2PS_TEXT_TL;
+      else if (va == 1)
+	gl2psa=GL2PS_TEXT_CL;
+    }
+  else if (ha == 2)
+    {
+      if (va == 0 || va == 3)
+	gl2psa=GL2PS_TEXT_BR;
+      else if (va == 2)
+	gl2psa=GL2PS_TEXT_TR;
+      else if (va == 1)
+	gl2psa=GL2PS_TEXT_CR;
+    }
+  else if (ha == 1)
+    {
+      if (va == 0 || va == 3)
+	gl2psa=GL2PS_TEXT_B;
+      else if (va == 2)
+	gl2psa=GL2PS_TEXT_T;
+      else if (va == 1)
+	gl2psa=GL2PS_TEXT_C;
+    }
+
+  glRasterPos3d (x, y, z);
+
+  gl2psTextOpt (txt.c_str (), fontname.c_str (), fontsize, gl2psa, rotation);
+
+  // FIXME -- we have no way of getting a bounding box from gl2ps
+  return retval;
+}
+
+void
+glps_renderer::set_font (const base_properties& props)
+{
+  fontsize = props.get ("fontsize").double_value ();
+
+  caseless_str fn = props.get ("fontname").string_value ();
+  fontname = "";
+  if (fn == "times" || fn == "times-roman")
+    fontname = "Times-Roman";
+  else if (fn == "courier")
+    fontname = "Courier";
+  else if (fn == "symbol")
+    fontname = "Symbol";
+  else if (fn == "zapfdingbats")
+    fontname = "ZapfDingbats";
+  else 
+    fontname = "Helvetica";
+
+  // FIXME -- add support for bold and italic
+}
+
+#endif
+
+/*
+;;; Local Variables: ***
+;;; mode: C++ ***
+;;; End: ***
+*/

new file mode 100644
--- /dev/null
+++ b/src/gl2ps-renderer.h
@@ -0,0 +1,86 @@
+/*
+
+Copyright (C) 2009 Shai Ayal
+
+This file is part of Octave.
+
+Octave 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 3 of the License, or (at your
+option) any later version.
+
+Octave 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.
+
+You should have received a copy of the GNU General Public License
+along with Octave; see the file COPYING.  If not, see
+<http://www.gnu.org/licenses/>.
+
+*/
+
+#if !defined (gl2ps_renderer_h)
+#define gl2ps_renderer_h 1
+
+#include "gl-render.h"
+#include "gl2ps.h"
+
+class 
+OCTINTERP_API
+glps_renderer : public opengl_renderer
+{
+public:
+  glps_renderer (const std::string& _filename) 
+    : opengl_renderer () , filename (_filename) { }
+
+  ~glps_renderer (void) { }
+
+  virtual void draw (const graphics_object& go);
+
+protected:
+
+  virtual Matrix render_text (const std::string& txt,
+			      double x, double y, double z,
+			      int halign, int valign, double rotation = 0.0);
+
+
+  virtual void set_font (const base_properties& props);
+
+  virtual void set_linestyle (const std::string& s, bool use_stipple)
+  {
+    opengl_renderer::set_linestyle (s, use_stipple);
+    if (use_stipple)
+      gl2psEnable (GL2PS_LINE_STIPPLE);
+    else
+      gl2psDisable (GL2PS_LINE_STIPPLE);
+  }
+
+  virtual void set_polygon_offset (bool on, double offset = 0.0)
+  {
+    opengl_renderer::set_polygon_offset (on, offset);
+    if (on)
+      gl2psEnable (GL2PS_POLYGON_OFFSET_FILL);
+    else
+      gl2psDisable (GL2PS_POLYGON_OFFSET_FILL);
+  }
+
+  virtual void set_linewidth (float w)
+  {
+    gl2psLineWidth (w);
+  }
+
+private:
+  std::string filename;
+  double fontsize;
+  std::string fontname;
+};
+
+#endif
+
+/*
+;;; Local Variables: ***
+;;; mode: C++ ***
+;;; End: ***
+*/
+

new file mode 100644
--- /dev/null
+++ b/src/gl2ps.c
@@ -0,0 +1,6013 @@
+/*
+ * GL2PS, an OpenGL to PostScript Printing Library
+ * Copyright (C) 1999-2009 C. Geuzaine
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of either:
+ *
+ * a) the GNU Library General Public License as published by the Free
+ * Software Foundation, either version 2 of the License, or (at your
+ * option) any later version; or
+ *
+ * b) the GL2PS License as published by Christophe Geuzaine, either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This program 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 either
+ * the GNU Library General Public License or the GL2PS License for
+ * more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library in the file named "COPYING.LGPL";
+ * if not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+ * Cambridge, MA 02139, USA.
+ *
+ * You should have received a copy of the GL2PS License with this
+ * library in the file named "COPYING.GL2PS"; if not, I will be glad
+ * to provide one.
+ *
+ * For the latest info about gl2ps and a full list of contributors,
+ * see http://www.geuz.org/gl2ps/.
+ *
+ * Please report all bugs and problems to <gl2ps@geuz.org>.
+ */
+
+#include "gl2ps.h"
+
+#include <math.h>
+#include <string.h>
+#include <sys/types.h>
+#include <stdarg.h>
+#include <time.h>
+#include <float.h>
+
+#if defined(GL2PS_HAVE_ZLIB)
+#include <zlib.h>
+#endif
+
+#if defined(GL2PS_HAVE_LIBPNG)
+#include <png.h>
+#endif
+
+/********************************************************************* 
+ *
+ * Private definitions, data structures and prototypes
+ *
+ *********************************************************************/
+
+/* Magic numbers (assuming that the order of magnitude of window
+   coordinates is 10^3) */
+
+#define GL2PS_EPSILON       5.0e-3F
+#define GL2PS_ZSCALE        1000.0F
+#define GL2PS_ZOFFSET       5.0e-2F
+#define GL2PS_ZOFFSET_LARGE 20.0F
+#define GL2PS_ZERO(arg)     (fabs(arg) < 1.e-20)
+
+/* Primitive types */
+
+#define GL2PS_NO_TYPE          -1
+#define GL2PS_TEXT             1
+#define GL2PS_POINT            2
+#define GL2PS_LINE             3
+#define GL2PS_QUADRANGLE       4
+#define GL2PS_TRIANGLE         5
+#define GL2PS_PIXMAP           6
+#define GL2PS_IMAGEMAP         7
+#define GL2PS_IMAGEMAP_WRITTEN 8
+#define GL2PS_IMAGEMAP_VISIBLE 9
+#define GL2PS_SPECIAL          10
+
+/* BSP tree primitive comparison */
+
+#define GL2PS_COINCIDENT  1
+#define GL2PS_IN_FRONT_OF 2
+#define GL2PS_IN_BACK_OF  3
+#define GL2PS_SPANNING    4
+
+/* 2D BSP tree primitive comparison */
+
+#define GL2PS_POINT_COINCIDENT 0
+#define GL2PS_POINT_INFRONT    1
+#define GL2PS_POINT_BACK       2
+
+/* Internal feedback buffer pass-through tokens */
+
+#define GL2PS_BEGIN_OFFSET_TOKEN   1
+#define GL2PS_END_OFFSET_TOKEN     2
+#define GL2PS_BEGIN_BOUNDARY_TOKEN 3
+#define GL2PS_END_BOUNDARY_TOKEN   4
+#define GL2PS_BEGIN_STIPPLE_TOKEN  5
+#define GL2PS_END_STIPPLE_TOKEN    6
+#define GL2PS_POINT_SIZE_TOKEN     7
+#define GL2PS_LINE_WIDTH_TOKEN     8
+#define GL2PS_BEGIN_BLEND_TOKEN    9
+#define GL2PS_END_BLEND_TOKEN      10
+#define GL2PS_SRC_BLEND_TOKEN      11
+#define GL2PS_DST_BLEND_TOKEN      12
+#define GL2PS_IMAGEMAP_TOKEN       13
+#define GL2PS_DRAW_PIXELS_TOKEN    14
+#define GL2PS_TEXT_TOKEN           15
+
+typedef enum {
+  T_UNDEFINED    = -1,
+  T_CONST_COLOR  = 1,
+  T_VAR_COLOR    = 1<<1,
+  T_ALPHA_1      = 1<<2,
+  T_ALPHA_LESS_1 = 1<<3,
+  T_VAR_ALPHA    = 1<<4
+} GL2PS_TRIANGLE_PROPERTY;
+
+typedef GLfloat GL2PSxyz[3];
+typedef GLfloat GL2PSplane[4];
+
+typedef struct _GL2PSbsptree2d GL2PSbsptree2d;
+
+struct _GL2PSbsptree2d {
+  GL2PSplane plane;
+  GL2PSbsptree2d *front, *back;
+};
+
+typedef struct {
+  GLint nmax, size, incr, n;
+  char *array;
+} GL2PSlist;
+
+typedef struct _GL2PSbsptree GL2PSbsptree;
+
+struct _GL2PSbsptree {
+  GL2PSplane plane;
+  GL2PSlist *primitives;
+  GL2PSbsptree *front, *back;
+};
+
+typedef struct {
+  GL2PSxyz xyz;
+  GL2PSrgba rgba;
+} GL2PSvertex;
+
+typedef struct {
+  GL2PSvertex vertex[3];
+  int prop;
+} GL2PStriangle;
+
+typedef struct {
+  GLshort fontsize;
+  char *str, *fontname;
+  /* Note: for a 'special' string, 'alignment' holds the format
+     (PostScript, PDF, etc.) of the special string */
+  GLint alignment;
+  GLfloat angle;
+} GL2PSstring;
+
+typedef struct {
+  GLsizei width, height;
+  /* Note: for an imagemap, 'type' indicates if it has already been
+     written to the file or not, and 'format' indicates if it is
+     visible or not */
+  GLenum format, type;
+  GLfloat *pixels;
+} GL2PSimage;
+
+typedef struct _GL2PSimagemap GL2PSimagemap;
+
+struct _GL2PSimagemap {
+  GL2PSimage *image;
+  GL2PSimagemap *next;
+};
+
+typedef struct {
+  GLshort type, numverts;
+  GLushort pattern;
+  char boundary, offset, culled;
+  GLint factor;
+  GLfloat width;
+  GL2PSvertex *verts;
+  union {
+    GL2PSstring *text;
+    GL2PSimage *image;
+  } data;
+} GL2PSprimitive;
+
+typedef struct {
+#if defined(GL2PS_HAVE_ZLIB)
+  Bytef *dest, *src, *start;
+  uLongf destLen, srcLen;
+#else
+  int dummy;
+#endif
+} GL2PScompress;
+
+typedef struct{
+  GL2PSlist* ptrlist;
+  int gsno, fontno, imno, shno, maskshno, trgroupno;
+  int gsobjno, fontobjno, imobjno, shobjno, maskshobjno, trgroupobjno;
+} GL2PSpdfgroup;
+
+typedef struct {
+  /* General */
+  GLint format, sort, options, colorsize, colormode, buffersize;
+  char *title, *producer, *filename;
+  GLboolean boundary, blending;
+  GLfloat *feedback, offset[2], lastlinewidth;
+  GLint viewport[4], blendfunc[2], lastfactor;
+  GL2PSrgba *colormap, lastrgba, threshold, bgcolor;
+  GLushort lastpattern;
+  GL2PSvertex lastvertex;
+  GL2PSlist *primitives, *auxprimitives;
+  FILE *stream;
+  GL2PScompress *compress;
+  GLboolean header;
+
+  /* BSP-specific */
+  GLint maxbestroot;
+
+  /* Occlusion culling-specific */
+  GLboolean zerosurfacearea;
+  GL2PSbsptree2d *imagetree;
+  GL2PSprimitive *primitivetoadd;
+  
+  /* PDF-specific */
+  int streamlength;
+  GL2PSlist *pdfprimlist, *pdfgrouplist;
+  int *xreflist;
+  int objects_stack; /* available objects */
+  int extgs_stack; /* graphics state object number */
+  int font_stack; /* font object number */
+  int im_stack; /* image object number */
+  int trgroupobjects_stack; /* xobject numbers */
+  int shader_stack; /* shader object numbers */
+  int mshader_stack; /* mask shader object numbers */
+
+  /* for image map list */
+  GL2PSimagemap *imagemap_head;
+  GL2PSimagemap *imagemap_tail;
+} GL2PScontext;
+
+typedef struct {
+  void  (*printHeader)(void);
+  void  (*printFooter)(void);
+  void  (*beginViewport)(GLint viewport[4]);
+  GLint (*endViewport)(void);
+  void  (*printPrimitive)(void *data);
+  void  (*printFinalPrimitive)(void);
+  const char *file_extension;
+  const char *description;
+} GL2PSbackend;
+
+/* The gl2ps context. gl2ps is not thread safe (we should create a
+   local GL2PScontext during gl2psBeginPage) */
+
+static GL2PScontext *gl2ps = NULL;
+
+/* Need to forward-declare this one */
+
+static GLint gl2psPrintPrimitives(void);
+
+/********************************************************************* 
+ *
+ * Utility routines
+ *
+ *********************************************************************/
+
+static void gl2psMsg(GLint level, const char *fmt, ...)
+{
+  va_list args;
+
+  if(!(gl2ps->options & GL2PS_SILENT)){
+    switch(level){
+    case GL2PS_INFO : fprintf(stderr, "GL2PS info: "); break;
+    case GL2PS_WARNING : fprintf(stderr, "GL2PS warning: "); break;
+    case GL2PS_ERROR : fprintf(stderr, "GL2PS error: "); break;
+    }
+    va_start(args, fmt);
+    vfprintf(stderr, fmt, args); 
+    va_end(args);
+    fprintf(stderr, "\n");
+  }
+  /* if(level == GL2PS_ERROR) exit(1); */
+}
+
+static void *gl2psMalloc(size_t size)
+{
+  void *ptr;
+
+  if(!size) return(NULL);
+  ptr = malloc(size);
+  if(!ptr){
+    gl2psMsg(GL2PS_ERROR, "Couldn't allocate requested memory");
+    exit(1);
+  }
+  return(ptr);
+}
+
+static void *gl2psRealloc(void *ptr, size_t size)
+{
+  if(!size) return(NULL);
+  ptr = realloc(ptr, size);
+  if(!ptr){
+    gl2psMsg(GL2PS_ERROR, "Couldn't reallocate requested memory");
+    exit(1);
+  }
+  return(ptr);
+}
+
+static void gl2psFree(void *ptr)
+{
+  if(!ptr) return;
+  free(ptr);
+}
+
+static size_t gl2psWriteBigEndian(unsigned long data, size_t bytes)
+{
+  size_t i;
+  size_t size = sizeof(unsigned long);
+  for(i = 1; i <= bytes; ++i){
+    fputc(0xff & (data >> (size-i) * 8), gl2ps->stream);
+  }
+  return bytes;
+}
+
+/* zlib compression helper routines */
+
+#if defined(GL2PS_HAVE_ZLIB)
+
+static void gl2psSetupCompress(void)
+{
+  gl2ps->compress = (GL2PScompress*)gl2psMalloc(sizeof(GL2PScompress));
+  gl2ps->compress->src = NULL;
+  gl2ps->compress->start = NULL;
+  gl2ps->compress->dest = NULL;
+  gl2ps->compress->srcLen = 0;
+  gl2ps->compress->destLen = 0;
+}
+
+static void gl2psFreeCompress(void)
+{
+  if(!gl2ps->compress)
+    return;
+  gl2psFree(gl2ps->compress->start);
+  gl2psFree(gl2ps->compress->dest);
+  gl2ps->compress->src = NULL;
+  gl2ps->compress->start = NULL;
+  gl2ps->compress->dest = NULL;
+  gl2ps->compress->srcLen = 0;
+  gl2ps->compress->destLen = 0;
+}
+
+static int gl2psAllocCompress(unsigned int srcsize)
+{
+  gl2psFreeCompress();
+  
+  if(!gl2ps->compress || !srcsize)
+    return GL2PS_ERROR;
+  
+  gl2ps->compress->srcLen = srcsize;
+  gl2ps->compress->destLen = (int)ceil(1.001 * gl2ps->compress->srcLen + 12);
+  gl2ps->compress->src = (Bytef*)gl2psMalloc(gl2ps->compress->srcLen);
+  gl2ps->compress->start = gl2ps->compress->src;
+  gl2ps->compress->dest = (Bytef*)gl2psMalloc(gl2ps->compress->destLen);
+  
+  return GL2PS_SUCCESS;
+}
+
+static void *gl2psReallocCompress(unsigned int srcsize)
+{
+  if(!gl2ps->compress || !srcsize)
+    return NULL;
+  
+  if(srcsize < gl2ps->compress->srcLen)
+    return gl2ps->compress->start;
+  
+  gl2ps->compress->srcLen = srcsize;
+  gl2ps->compress->destLen = (int)ceil(1.001 * gl2ps->compress->srcLen + 12);
+  gl2ps->compress->src = (Bytef*)gl2psRealloc(gl2ps->compress->src, 
+                                              gl2ps->compress->srcLen);
+  gl2ps->compress->start = gl2ps->compress->src;
+  gl2ps->compress->dest = (Bytef*)gl2psRealloc(gl2ps->compress->dest, 
+                                               gl2ps->compress->destLen);
+  
+  return gl2ps->compress->start;
+}
+
+static size_t gl2psWriteBigEndianCompress(unsigned long data, size_t bytes)
+{
+  size_t i;
+  size_t size = sizeof(unsigned long);
+  for(i = 1; i <= bytes; ++i){
+    *gl2ps->compress->src = (Bytef)(0xff & (data >> (size-i) * 8));
+    ++gl2ps->compress->src;
+  }
+  return bytes;
+}
+
+static int gl2psDeflate(void)
+{
+  /* For compatibility with older zlib versions, we use compress(...)
+     instead of compress2(..., Z_BEST_COMPRESSION) */
+  return compress(gl2ps->compress->dest, &gl2ps->compress->destLen, 
+                  gl2ps->compress->start, gl2ps->compress->srcLen);  
+}
+
+#endif
+
+static int gl2psPrintf(const char* fmt, ...)
+{
+  int ret;
+  va_list args;
+
+#if defined(GL2PS_HAVE_ZLIB)
+  unsigned int oldsize = 0;
+  static char buf[1000];
+  if(gl2ps->options & GL2PS_COMPRESS){
+    va_start(args, fmt);
+    ret = vsprintf(buf, fmt, args);
+    va_end(args);
+    oldsize = gl2ps->compress->srcLen;
+    gl2ps->compress->start = (Bytef*)gl2psReallocCompress(oldsize + ret);
+    memcpy(gl2ps->compress->start+oldsize, buf, ret);
+    ret = 0;
+  }
+  else{
+#endif
+    va_start(args, fmt);
+    ret = vfprintf(gl2ps->stream, fmt, args);
+    va_end(args);
+#if defined(GL2PS_HAVE_ZLIB)
+  }
+#endif
+  return ret;
+}
+
+static void gl2psPrintGzipHeader()
+{
+#if defined(GL2PS_HAVE_ZLIB)
+  char tmp[10] = {'\x1f', '\x8b', /* magic numbers: 0x1f, 0x8b */
+                  8, /* compression method: Z_DEFLATED */
+                  0, /* flags */
+                  0, 0, 0, 0, /* time */
+                  2, /* extra flags: max compression */
+                  '\x03'}; /* OS code: 0x03 (Unix) */
+
+  if(gl2ps->options & GL2PS_COMPRESS){
+    gl2psSetupCompress();
+    /* add the gzip file header */
+    fwrite(tmp, 10, 1, gl2ps->stream);
+  }
+#endif  
+}
+
+static void gl2psPrintGzipFooter()
+{
+#if defined(GL2PS_HAVE_ZLIB)
+  int n;
+  uLong crc, len;
+  char tmp[8];
+
+  if(gl2ps->options & GL2PS_COMPRESS){
+    if(Z_OK != gl2psDeflate()){
+      gl2psMsg(GL2PS_ERROR, "Zlib deflate error");
+    }
+    else{
+      /* determine the length of the header in the zlib stream */
+      n = 2; /* CMF+FLG */
+      if(gl2ps->compress->dest[1] & (1<<5)){
+        n += 4; /* DICTID */
+      }
+      /* write the data, without the zlib header and footer */
+      fwrite(gl2ps->compress->dest+n, gl2ps->compress->destLen-(n+4), 
+             1, gl2ps->stream);
+      /* add the gzip file footer */
+      crc = crc32(0L, gl2ps->compress->start, gl2ps->compress->srcLen);
+      for(n = 0; n < 4; ++n){
+        tmp[n] = (char)(crc & 0xff);
+        crc >>= 8;
+      }
+      len = gl2ps->compress->srcLen;
+      for(n = 4; n < 8; ++n){
+        tmp[n] = (char)(len & 0xff);
+        len >>= 8;
+      }
+      fwrite(tmp, 8, 1, gl2ps->stream);
+    }
+    gl2psFreeCompress();
+    gl2psFree(gl2ps->compress);
+    gl2ps->compress = NULL;
+  }
+#endif 
+}
+
+/* The list handling routines */
+
+static void gl2psListRealloc(GL2PSlist *list, GLint n)
+{
+  if(!list){
+    gl2psMsg(GL2PS_ERROR, "Cannot reallocate NULL list");
+    return;
+  }
+  if(n <= 0) return;
+  if(!list->array){
+    list->nmax = n;
+    list->array = (char*)gl2psMalloc(list->nmax * list->size);
+  }
+  else{
+    if(n > list->nmax){
+      list->nmax = ((n - 1) / list->incr + 1) * list->incr;
+      list->array = (char*)gl2psRealloc(list->array,
+                                        list->nmax * list->size);
+    }
+  }
+}
+
+static GL2PSlist *gl2psListCreate(GLint n, GLint incr, GLint size)
+{
+  GL2PSlist *list;
+
+  if(n < 0) n = 0;
+  if(incr <= 0) incr = 1;
+  list = (GL2PSlist*)gl2psMalloc(sizeof(GL2PSlist));
+  list->nmax = 0;
+  list->incr = incr;
+  list->size = size;
+  list->n = 0;
+  list->array = NULL;
+  gl2psListRealloc(list, n);
+  return(list);
+}
+
+static void gl2psListReset(GL2PSlist *list)
+{
+  if(!list) return;
+  list->n = 0;
+}
+
+static void gl2psListDelete(GL2PSlist *list)
+{
+  if(!list) return;  
+  gl2psFree(list->array);
+  gl2psFree(list);
+}
+
+static void gl2psListAdd(GL2PSlist *list, void *data)
+{
+  if(!list){
+    gl2psMsg(GL2PS_ERROR, "Cannot add into unallocated list");
+    return;
+  }
+  list->n++;
+  gl2psListRealloc(list, list->n);
+  memcpy(&list->array[(list->n - 1) * list->size], data, list->size);
+}
+
+static int gl2psListNbr(GL2PSlist *list)
+{
+  if(!list)
+    return 0;
+  return(list->n);
+}
+
+static void *gl2psListPointer(GL2PSlist *list, GLint index)
+{
+  if(!list){
+    gl2psMsg(GL2PS_ERROR, "Cannot point into unallocated list");
+    return NULL;
+  }
+  if((index < 0) || (index >= list->n)){
+    gl2psMsg(GL2PS_ERROR, "Wrong list index in gl2psListPointer");
+    return NULL;
+  }
+  return(&list->array[index * list->size]);
+}
+
+static void gl2psListSort(GL2PSlist *list,
+                          int (*fcmp)(const void *a, const void *b))
+{
+  if(!list)
+    return;
+  qsort(list->array, list->n, list->size, fcmp);
+}
+
+static void gl2psListAction(GL2PSlist *list, void (*action)(void *data))
+{
+  GLint i;
+
+  for(i = 0; i < gl2psListNbr(list); i++){
+    (*action)(gl2psListPointer(list, i));
+  }
+}
+
+static void gl2psListActionInverse(GL2PSlist *list, void (*action)(void *data))
+{
+  GLint i;
+
+  for(i = gl2psListNbr(list); i > 0; i--){
+    (*action)(gl2psListPointer(list, i-1));
+  }
+}
+
+#if defined(GL2PS_HAVE_LIBPNG)
+
+static void gl2psListRead(GL2PSlist *list, int index, void *data)
+{
+  if((index < 0) || (index >= list->n))
+    gl2psMsg(GL2PS_ERROR, "Wrong list index in gl2psListRead");
+  memcpy(data, &list->array[index * list->size], list->size);
+}
+
+static void gl2psEncodeBase64Block(unsigned char in[3], unsigned char out[4], int len)
+{
+  static const char cb64[] = 
+    "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+  out[0] = cb64[ in[0] >> 2 ];
+  out[1] = cb64[ ((in[0] & 0x03) << 4) | ((in[1] & 0xf0) >> 4) ];
+  out[2] = (len > 1) ? cb64[ ((in[1] & 0x0f) << 2) | ((in[2] & 0xc0) >> 6) ] : '=';
+  out[3] = (len > 2) ? cb64[ in[2] & 0x3f ] : '=';
+}
+
+static void gl2psListEncodeBase64(GL2PSlist *list)
+{
+  unsigned char *buffer, in[3], out[4];
+  int i, n, index, len;
+
+  n = list->n * list->size;
+  buffer = (unsigned char*)gl2psMalloc(n * sizeof(unsigned char));
+  memcpy(buffer, list->array, n * sizeof(unsigned char));
+  gl2psListReset(list);
+
+  index = 0;
+  while(index < n) {
+    len = 0;
+    for(i = 0; i < 3; i++) {
+      if(index < n){
+        in[i] = buffer[index];
+        len++;
+      }
+      else{
+        in[i] = 0;
+      }
+      index++;
+    }
+    if(len) {
+      gl2psEncodeBase64Block(in, out, len);
+      for(i = 0; i < 4; i++)
+        gl2psListAdd(list, &out[i]);
+    }
+  }
+  gl2psFree(buffer);
+}
+
+#endif
+
+/* Helpers for rgba colors */
+
+static GLboolean gl2psSameColor(GL2PSrgba rgba1, GL2PSrgba rgba2)
+{
+  if(!GL2PS_ZERO(rgba1[0] - rgba2[0]) ||
+     !GL2PS_ZERO(rgba1[1] - rgba2[1]) ||
+     !GL2PS_ZERO(rgba1[2] - rgba2[2]))
+    return GL_FALSE;
+  return GL_TRUE;
+}
+  
+static GLboolean gl2psVertsSameColor(const GL2PSprimitive *prim)
+{
+  int i;
+
+  for(i = 1; i < prim->numverts; i++){
+    if(!gl2psSameColor(prim->verts[0].rgba, prim->verts[i].rgba)){
+      return GL_FALSE;
+    }
+  }
+  return GL_TRUE;
+}
+
+static GLboolean gl2psSameColorThreshold(int n, GL2PSrgba rgba[],
+                                         GL2PSrgba threshold)
+{
+  int i;
+
+  if(n < 2) return GL_TRUE;
+  
+  for(i = 1; i < n; i++){
+    if(fabs(rgba[0][0] - rgba[i][0]) > threshold[0] ||
+       fabs(rgba[0][1] - rgba[i][1]) > threshold[1] ||
+       fabs(rgba[0][2] - rgba[i][2]) > threshold[2])
+      return GL_FALSE;
+  }
+  
+  return GL_TRUE;
+}
+
+static void gl2psSetLastColor(GL2PSrgba rgba)
+{
+  int i;        
+  for(i = 0; i < 3; ++i){
+    gl2ps->lastrgba[i] = rgba[i];
+  }
+}
+
+static GLfloat gl2psGetRGB(GL2PSimage *im, GLuint x, GLuint y,
+                           GLfloat *red, GLfloat *green, GLfloat *blue)
+{
+  
+  GLsizei width = im->width;
+  GLsizei height = im->height;
+  GLfloat *pixels = im->pixels;
+  GLfloat *pimag;
+
+  /* OpenGL image is from down to up, PS image is up to down */  
+  switch(im->format){
+  case GL_RGBA:
+    pimag = pixels + 4 * (width * (height - 1 - y) + x);
+    break;
+  case GL_RGB:
+  default:
+    pimag = pixels + 3 * (width * (height - 1 - y) + x);
+    break;
+  }
+  *red = *pimag; pimag++;
+  *green = *pimag; pimag++;
+  *blue = *pimag; pimag++;
+
+  return (im->format == GL_RGBA) ? *pimag : 1.0F;
+}
+
+/* Helper routines for pixmaps */
+
+static GL2PSimage *gl2psCopyPixmap(GL2PSimage *im)
+{
+  int size;
+  GL2PSimage *image = (GL2PSimage*)gl2psMalloc(sizeof(GL2PSimage));
+  
+  image->width = im->width;
+  image->height = im->height;
+  image->format = im->format;
+  image->type = im->type;
+
+  switch(image->format){
+  case GL_RGBA:
+    size = image->height * image->width * 4 * sizeof(GLfloat);
+    break;
+  case GL_RGB:
+  default:
+    size = image->height * image->width * 3 * sizeof(GLfloat);
+    break;
+  }
+
+  image->pixels = (GLfloat*)gl2psMalloc(size);
+  memcpy(image->pixels, im->pixels, size);
+  
+  return image;
+}
+
+static void gl2psFreePixmap(GL2PSimage *im)
+{
+  if(!im)
+    return;
+  gl2psFree(im->pixels);
+  gl2psFree(im);
+}
+
+#if defined(GL2PS_HAVE_LIBPNG)
+
+#if !defined(png_jmpbuf)
+#  define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)
+#endif
+
+static void gl2psUserWritePNG(png_structp png_ptr, png_bytep data, png_size_t length)
+{
+  unsigned int i;
+  GL2PSlist *png = (GL2PSlist*)png_get_io_ptr(png_ptr);
+  for(i = 0; i < length; i++) 
+    gl2psListAdd(png, &data[i]);
+}
+
+static void gl2psUserFlushPNG(png_structp png_ptr)
+{
+}
+
+static void gl2psConvertPixmapToPNG(GL2PSimage *pixmap, GL2PSlist *png)
+{
+  png_structp png_ptr;
+  png_infop info_ptr;
+  unsigned char *row_data;
+  GLfloat dr, dg, db;
+  int row, col;
+
+  if(!(png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL)))
+    return;
+  
+  if(!(info_ptr = png_create_info_struct(png_ptr))){
+    png_destroy_write_struct(&png_ptr, NULL);
+    return;
+  }
+  
+  if(setjmp(png_jmpbuf(png_ptr))) {
+    png_destroy_write_struct(&png_ptr, &info_ptr);
+    return;
+  }
+  
+  png_set_write_fn(png_ptr, (void *)png, gl2psUserWritePNG, gl2psUserFlushPNG);
+  png_set_compression_level(png_ptr, Z_DEFAULT_COMPRESSION);
+  png_set_IHDR(png_ptr, info_ptr, pixmap->width, pixmap->height, 8, 
+               PNG_COLOR_TYPE_RGB, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE, 
+               PNG_FILTER_TYPE_BASE);
+  png_write_info(png_ptr, info_ptr);
+
+  row_data = (unsigned char*)gl2psMalloc(3 * pixmap->width * sizeof(unsigned char));
+  for(row = 0; row < pixmap->height; row++){
+    for(col = 0; col < pixmap->width; col++){
+      gl2psGetRGB(pixmap, col, row, &dr, &dg, &db);
+      row_data[3*col] = (unsigned char)(255. * dr);
+      row_data[3*col+1] = (unsigned char)(255. * dg);
+      row_data[3*col+2] = (unsigned char)(255. * db);
+    }
+    png_write_row(png_ptr, (png_bytep)row_data);
+  }
+  gl2psFree(row_data);
+
+  png_write_end(png_ptr, info_ptr);
+  png_destroy_write_struct(&png_ptr, &info_ptr);
+}
+
+#endif
+
+/* Helper routines for text strings */
+
+static GLint gl2psAddText(GLint type, const char *str, const char *fontname, 
+                          GLshort fontsize, GLint alignment, GLfloat angle)
+{
+  GLfloat pos[4];
+  GL2PSprimitive *prim;
+  GLboolean valid;
+
+  if(!gl2ps || !str || !fontname) return GL2PS_UNINITIALIZED;
+
+  if(gl2ps->options & GL2PS_NO_TEXT) return GL2PS_SUCCESS;
+
+  glGetBooleanv(GL_CURRENT_RASTER_POSITION_VALID, &valid);
+  if(GL_FALSE == valid) return GL2PS_SUCCESS; /* the primitive is culled */
+
+  glGetFloatv(GL_CURRENT_RASTER_POSITION, pos);
+
+  prim = (GL2PSprimitive*)gl2psMalloc(sizeof(GL2PSprimitive));
+  prim->type = type;
+  prim->boundary = 0;
+  prim->numverts = 1;
+  prim->verts = (GL2PSvertex*)gl2psMalloc(sizeof(GL2PSvertex));
+  prim->verts[0].xyz[0] = pos[0];
+  prim->verts[0].xyz[1] = pos[1];
+  prim->verts[0].xyz[2] = pos[2];
+  prim->culled = 0;
+  prim->offset = 0;
+  prim->pattern = 0;
+  prim->factor = 0;
+  prim->width = 1;
+  glGetFloatv(GL_CURRENT_RASTER_COLOR, prim->verts[0].rgba);
+  prim->data.text = (GL2PSstring*)gl2psMalloc(sizeof(GL2PSstring));
+  prim->data.text->str = (char*)gl2psMalloc((strlen(str)+1)*sizeof(char));
+  strcpy(prim->data.text->str, str); 
+  prim->data.text->fontname = (char*)gl2psMalloc((strlen(fontname)+1)*sizeof(char));
+  strcpy(prim->data.text->fontname, fontname);
+  prim->data.text->fontsize = fontsize;
+  prim->data.text->alignment = alignment;
+  prim->data.text->angle = angle;
+
+  gl2psListAdd(gl2ps->auxprimitives, &prim);
+  glPassThrough(GL2PS_TEXT_TOKEN);
+    
+  return GL2PS_SUCCESS;
+}
+
+static GL2PSstring *gl2psCopyText(GL2PSstring *t)
+{
+  GL2PSstring *text = (GL2PSstring*)gl2psMalloc(sizeof(GL2PSstring));
+  text->str = (char*)gl2psMalloc((strlen(t->str)+1)*sizeof(char));
+  strcpy(text->str, t->str); 
+  text->fontname = (char*)gl2psMalloc((strlen(t->fontname)+1)*sizeof(char));
+  strcpy(text->fontname, t->fontname);
+  text->fontsize = t->fontsize;
+  text->alignment = t->alignment;
+  text->angle = t->angle;
+  
+  return text;
+}
+
+static void gl2psFreeText(GL2PSstring *text)
+{
+  if(!text)
+    return;
+  gl2psFree(text->str);
+  gl2psFree(text->fontname);
+  gl2psFree(text);
+}
+
+/* Helpers for blending modes */
+
+static GLboolean gl2psSupportedBlendMode(GLenum sfactor, GLenum dfactor)
+{
+  /* returns TRUE if gl2ps supports the argument combination: only two
+     blending modes have been implemented so far */
+
+  if( (sfactor == GL_SRC_ALPHA && dfactor == GL_ONE_MINUS_SRC_ALPHA) || 
+      (sfactor == GL_ONE && dfactor == GL_ZERO) )
+    return GL_TRUE;
+  return GL_FALSE;
+}
+
+static void gl2psAdaptVertexForBlending(GL2PSvertex *v)
+{
+  /* Transforms vertex depending on the actual blending function -
+     currently the vertex v is considered as source vertex and his
+     alpha value is changed to 1.0 if source blending GL_ONE is
+     active. This might be extended in the future */
+
+  if(!v || !gl2ps)
+    return;
+
+  if(gl2ps->options & GL2PS_NO_BLENDING || !gl2ps->blending){
+    v->rgba[3] = 1.0F;
+    return;
+  }
+  
+  switch(gl2ps->blendfunc[0]){
+  case GL_ONE:
+    v->rgba[3] = 1.0F;
+    break;
+  default:
+    break;
+  }
+}
+
+static void gl2psAssignTriangleProperties(GL2PStriangle *t)
+{
+  /* int i; */
+
+  t->prop = T_VAR_COLOR;
+
+  /* Uncommenting the following lines activates an even more fine
+     grained distinction between triangle types - please don't delete,
+     a remarkable amount of PDF handling code inside this file depends
+     on it if activated */
+  /*
+  t->prop = T_CONST_COLOR;    
+  for(i = 0; i < 3; ++i){
+    if(!GL2PS_ZERO(t->vertex[0].rgba[i] - t->vertex[1].rgba[i]) || 
+       !GL2PS_ZERO(t->vertex[1].rgba[i] - t->vertex[2].rgba[i])){
+      t->prop = T_VAR_COLOR;
+      break;
+    }
+  }
+  */
+
+  if(!GL2PS_ZERO(t->vertex[0].rgba[3] - t->vertex[1].rgba[3]) || 
+     !GL2PS_ZERO(t->vertex[1].rgba[3] - t->vertex[2].rgba[3])){
+    t->prop |= T_VAR_ALPHA;
+  }
+  else{
+    if(t->vertex[0].rgba[3] < 1)
+      t->prop |= T_ALPHA_LESS_1;
+    else
+      t->prop |= T_ALPHA_1;
+  }
+}
+
+static void gl2psFillTriangleFromPrimitive(GL2PStriangle *t, GL2PSprimitive *p,
+                                           GLboolean assignprops)
+{
+  t->vertex[0] = p->verts[0];
+  t->vertex[1] = p->verts[1];
+  t->vertex[2] = p->verts[2];
+  if(GL_TRUE == assignprops)
+    gl2psAssignTriangleProperties(t);
+}
+
+static void gl2psInitTriangle(GL2PStriangle *t)
+{
+  int i;
+  GL2PSvertex vertex = { {-1.0F, -1.0F, -1.0F}, {-1.0F, -1.0F, -1.0F, -1.0F} };
+  for(i = 0; i < 3; i++)
+    t->vertex[i] = vertex;
+  t->prop = T_UNDEFINED;
+}
+
+/* Miscellaneous helper routines */
+
+static GL2PSprimitive *gl2psCopyPrimitive(GL2PSprimitive *p)
+{
+  GL2PSprimitive *prim;
+
+  if(!p){
+    gl2psMsg(GL2PS_ERROR, "Trying to copy an empty primitive");
+    return NULL;
+  }
+
+  prim = (GL2PSprimitive*)gl2psMalloc(sizeof(GL2PSprimitive));
+  
+  prim->type = p->type;
+  prim->numverts = p->numverts;
+  prim->boundary = p->boundary;
+  prim->offset = p->offset;
+  prim->pattern = p->pattern;
+  prim->factor = p->factor;
+  prim->culled = p->culled;
+  prim->width = p->width;
+  prim->verts = (GL2PSvertex*)gl2psMalloc(p->numverts*sizeof(GL2PSvertex));
+  memcpy(prim->verts, p->verts, p->numverts * sizeof(GL2PSvertex));
+
+  switch(prim->type){
+  case GL2PS_PIXMAP :
+    prim->data.image = gl2psCopyPixmap(p->data.image);
+    break;
+  case GL2PS_TEXT :
+  case GL2PS_SPECIAL :
+    prim->data.text = gl2psCopyText(p->data.text);
+    break;
+  default:
+    break;
+  }
+
+  return prim;
+}
+
+static GLboolean gl2psSamePosition(GL2PSxyz p1, GL2PSxyz p2)
+{
+  if(!GL2PS_ZERO(p1[0] - p2[0]) ||
+     !GL2PS_ZERO(p1[1] - p2[1]) ||
+     !GL2PS_ZERO(p1[2] - p2[2]))
+    return GL_FALSE;
+  return GL_TRUE;
+}
+
+/********************************************************************* 
+ *
+ * 3D sorting routines 
+ *
+ *********************************************************************/
+
+static GLfloat gl2psComparePointPlane(GL2PSxyz point, GL2PSplane plane)
+{
+  return(plane[0] * point[0] + 
+         plane[1] * point[1] + 
+         plane[2] * point[2] + 
+         plane[3]);
+}
+
+static GLfloat gl2psPsca(GLfloat *a, GLfloat *b)
+{
+  return(a[0]*b[0] + a[1]*b[1] + a[2]*b[2]);
+}
+
+static void gl2psPvec(GLfloat *a, GLfloat *b, GLfloat *c)
+{
+  c[0] = a[1]*b[2] - a[2]*b[1];
+  c[1] = a[2]*b[0] - a[0]*b[2];
+  c[2] = a[0]*b[1] - a[1]*b[0];
+}
+
+static GLfloat gl2psNorm(GLfloat *a)
+{
+  return (GLfloat)sqrt(a[0]*a[0] + a[1]*a[1] + a[2]*a[2]);
+}
+
+static void gl2psGetNormal(GLfloat *a, GLfloat *b, GLfloat *c)
+{
+  GLfloat norm;
+
+  gl2psPvec(a, b, c);
+  if(!GL2PS_ZERO(norm = gl2psNorm(c))){
+    c[0] = c[0] / norm;
+    c[1] = c[1] / norm;
+    c[2] = c[2] / norm;
+  }
+  else{
+    /* The plane is still wrong despite our tests in gl2psGetPlane.
+       Let's return a dummy value for now (this is a hack: we should
+       do more intelligent tests in GetPlane) */
+    c[0] = c[1] = 0.0F;
+    c[2] = 1.0F;
+  }
+}
+
+static void gl2psGetPlane(GL2PSprimitive *prim, GL2PSplane plane)
+{
+  GL2PSxyz v = {0.0F, 0.0F, 0.0F}, w = {0.0F, 0.0F, 0.0F};
+
+  switch(prim->type){
+  case GL2PS_TRIANGLE :
+  case GL2PS_QUADRANGLE :
+    v[0] = prim->verts[1].xyz[0] - prim->verts[0].xyz[0]; 
+    v[1] = prim->verts[1].xyz[1] - prim->verts[0].xyz[1]; 
+    v[2] = prim->verts[1].xyz[2] - prim->verts[0].xyz[2]; 
+    w[0] = prim->verts[2].xyz[0] - prim->verts[0].xyz[0]; 
+    w[1] = prim->verts[2].xyz[1] - prim->verts[0].xyz[1]; 
+    w[2] = prim->verts[2].xyz[2] - prim->verts[0].xyz[2]; 
+    if((GL2PS_ZERO(v[0]) && GL2PS_ZERO(v[1]) && GL2PS_ZERO(v[2])) || 
+       (GL2PS_ZERO(w[0]) && GL2PS_ZERO(w[1]) && GL2PS_ZERO(w[2]))){
+      plane[0] = plane[1] = 0.0F;
+      plane[2] = 1.0F;
+      plane[3] = -prim->verts[0].xyz[2];
+    }
+    else{
+      gl2psGetNormal(v, w, plane);
+      plane[3] = 
+        - plane[0] * prim->verts[0].xyz[0] 
+        - plane[1] * prim->verts[0].xyz[1] 
+        - plane[2] * prim->verts[0].xyz[2];
+    }
+    break;
+  case GL2PS_LINE :
+    v[0] = prim->verts[1].xyz[0] - prim->verts[0].xyz[0]; 
+    v[1] = prim->verts[1].xyz[1] - prim->verts[0].xyz[1]; 
+    v[2] = prim->verts[1].xyz[2] - prim->verts[0].xyz[2]; 
+    if(GL2PS_ZERO(v[0]) && GL2PS_ZERO(v[1]) && GL2PS_ZERO(v[2])){
+      plane[0] = plane[1] = 0.0F;
+      plane[2] = 1.0F;
+      plane[3] = -prim->verts[0].xyz[2];
+    }
+    else{
+      if(GL2PS_ZERO(v[0]))      w[0] = 1.0F;
+      else if(GL2PS_ZERO(v[1])) w[1] = 1.0F;
+      else                      w[2] = 1.0F;
+      gl2psGetNormal(v, w, plane);
+      plane[3] = 
+        - plane[0] * prim->verts[0].xyz[0] 
+        - plane[1] * prim->verts[0].xyz[1] 
+        - plane[2] * prim->verts[0].xyz[2];
+    }
+    break;
+  case GL2PS_POINT :
+  case GL2PS_PIXMAP :
+  case GL2PS_TEXT :
+  case GL2PS_SPECIAL :
+  case GL2PS_IMAGEMAP:
+    plane[0] = plane[1] = 0.0F;
+    plane[2] = 1.0F;
+    plane[3] = -prim->verts[0].xyz[2];
+    break;
+  default :
+    gl2psMsg(GL2PS_ERROR, "Unknown primitive type in BSP tree");
+    plane[0] = plane[1] = plane[3] = 0.0F;
+    plane[2] = 1.0F;
+    break;
+  }
+}
+
+static void gl2psCutEdge(GL2PSvertex *a, GL2PSvertex *b, GL2PSplane plane,
+                         GL2PSvertex *c)
+{
+  GL2PSxyz v;
+  GLfloat sect, psca;
+
+  v[0] = b->xyz[0] - a->xyz[0];
+  v[1] = b->xyz[1] - a->xyz[1];
+  v[2] = b->xyz[2] - a->xyz[2];
+
+  if(!GL2PS_ZERO(psca = gl2psPsca(plane, v)))
+    sect = -gl2psComparePointPlane(a->xyz, plane) / psca;
+  else
+    sect = 0.0F;
+  
+  c->xyz[0] = a->xyz[0] + v[0] * sect;
+  c->xyz[1] = a->xyz[1] + v[1] * sect;
+  c->xyz[2] = a->xyz[2] + v[2] * sect;
+  
+  c->rgba[0] = (1 - sect) * a->rgba[0] + sect * b->rgba[0];
+  c->rgba[1] = (1 - sect) * a->rgba[1] + sect * b->rgba[1];
+  c->rgba[2] = (1 - sect) * a->rgba[2] + sect * b->rgba[2];
+  c->rgba[3] = (1 - sect) * a->rgba[3] + sect * b->rgba[3];
+}
+
+static void gl2psCreateSplitPrimitive(GL2PSprimitive *parent, GL2PSplane plane,
+                                      GL2PSprimitive *child, GLshort numverts,
+                                      GLshort *index0, GLshort *index1)
+{
+  GLshort i;
+
+  if(parent->type == GL2PS_IMAGEMAP){
+    child->type = GL2PS_IMAGEMAP;
+    child->data.image = parent->data.image;
+  }
+  else{
+    if(numverts > 4){
+      gl2psMsg(GL2PS_WARNING, "%d vertices in polygon", numverts);
+      numverts = 4;
+    }
+    switch(numverts){
+    case 1 : child->type = GL2PS_POINT; break; 
+    case 2 : child->type = GL2PS_LINE; break; 
+    case 3 : child->type = GL2PS_TRIANGLE; break; 
+    case 4 : child->type = GL2PS_QUADRANGLE; break;    
+    default: child->type = GL2PS_NO_TYPE; break;
+    }
+  }
+
+  child->boundary = 0; /* FIXME: not done! */
+  child->culled = parent->culled;
+  child->offset = parent->offset;
+  child->pattern = parent->pattern;
+  child->factor = parent->factor;
+  child->width = parent->width;
+  child->numverts = numverts;
+  child->verts = (GL2PSvertex*)gl2psMalloc(numverts * sizeof(GL2PSvertex));
+
+  for(i = 0; i < numverts; i++){
+    if(index1[i] < 0){
+      child->verts[i] = parent->verts[index0[i]];
+    }
+    else{
+      gl2psCutEdge(&parent->verts[index0[i]], &parent->verts[index1[i]], 
+                   plane, &child->verts[i]);
+    }
+  }
+}
+
+static void gl2psAddIndex(GLshort *index0, GLshort *index1, GLshort *nb, 
+                          GLshort i, GLshort j)
+{
+  GLint k;
+
+  for(k = 0; k < *nb; k++){
+    if((index0[k] == i && index1[k] == j) ||
+       (index1[k] == i && index0[k] == j)) return;
+  }
+  index0[*nb] = i;
+  index1[*nb] = j;
+  (*nb)++;
+}
+
+static GLshort gl2psGetIndex(GLshort i, GLshort num)
+{
+  return (i < num - 1) ? i + 1 : 0;
+}
+
+static GLint gl2psTestSplitPrimitive(GL2PSprimitive *prim, GL2PSplane plane)
+{
+  GLint type = GL2PS_COINCIDENT;
+  GLshort i, j;
+  GLfloat d[5]; 
+
+  for(i = 0; i < prim->numverts; i++){  
+    d[i] = gl2psComparePointPlane(prim->verts[i].xyz, plane);
+  }
+
+  if(prim->numverts < 2){
+    return 0;
+  }
+  else{
+    for(i = 0; i < prim->numverts; i++){
+      j = gl2psGetIndex(i, prim->numverts);
+      if(d[j] > GL2PS_EPSILON){
+        if(type == GL2PS_COINCIDENT)      type = GL2PS_IN_BACK_OF;
+        else if(type != GL2PS_IN_BACK_OF) return 1; 
+        if(d[i] < -GL2PS_EPSILON)         return 1;
+      }
+      else if(d[j] < -GL2PS_EPSILON){
+        if(type == GL2PS_COINCIDENT)       type = GL2PS_IN_FRONT_OF;   
+        else if(type != GL2PS_IN_FRONT_OF) return 1;
+        if(d[i] > GL2PS_EPSILON)           return 1;
+      }
+    }
+  }
+  return 0;
+}
+
+static GLint gl2psSplitPrimitive(GL2PSprimitive *prim, GL2PSplane plane, 
+                                 GL2PSprimitive **front, GL2PSprimitive **back)
+{
+  GLshort i, j, in = 0, out = 0, in0[5], in1[5], out0[5], out1[5];
+  GLint type;
+  GLfloat d[5]; 
+
+  type = GL2PS_COINCIDENT;
+
+  for(i = 0; i < prim->numverts; i++){  
+    d[i] = gl2psComparePointPlane(prim->verts[i].xyz, plane);
+  }
+
+  switch(prim->type){
+  case GL2PS_POINT :
+    if(d[0] > GL2PS_EPSILON)       type = GL2PS_IN_BACK_OF;
+    else if(d[0] < -GL2PS_EPSILON) type = GL2PS_IN_FRONT_OF;
+    else                           type = GL2PS_COINCIDENT;
+    break;
+  default :
+    for(i = 0; i < prim->numverts; i++){
+      j = gl2psGetIndex(i, prim->numverts);
+      if(d[j] > GL2PS_EPSILON){
+        if(type == GL2PS_COINCIDENT)      type = GL2PS_IN_BACK_OF;
+        else if(type != GL2PS_IN_BACK_OF) type = GL2PS_SPANNING; 
+        if(d[i] < -GL2PS_EPSILON){
+          gl2psAddIndex(in0, in1, &in, i, j);
+          gl2psAddIndex(out0, out1, &out, i, j);
+          type = GL2PS_SPANNING;
+        }
+        gl2psAddIndex(out0, out1, &out, j, -1);
+      }
+      else if(d[j] < -GL2PS_EPSILON){
+        if(type == GL2PS_COINCIDENT)       type = GL2PS_IN_FRONT_OF;   
+        else if(type != GL2PS_IN_FRONT_OF) type = GL2PS_SPANNING;
+        if(d[i] > GL2PS_EPSILON){
+          gl2psAddIndex(in0, in1, &in, i, j);
+          gl2psAddIndex(out0, out1, &out, i, j);
+          type = GL2PS_SPANNING;
+        }
+        gl2psAddIndex(in0, in1, &in, j, -1);
+      }
+      else{
+        gl2psAddIndex(in0, in1, &in, j, -1);
+        gl2psAddIndex(out0, out1, &out, j, -1);
+      }
+    }
+    break;
+  }
+
+  if(type == GL2PS_SPANNING){
+    *back = (GL2PSprimitive*)gl2psMalloc(sizeof(GL2PSprimitive));
+    *front = (GL2PSprimitive*)gl2psMalloc(sizeof(GL2PSprimitive));
+    gl2psCreateSplitPrimitive(prim, plane, *back, out, out0, out1);
+    gl2psCreateSplitPrimitive(prim, plane, *front, in, in0, in1);
+  }
+
+  return type;
+}
+
+static void gl2psDivideQuad(GL2PSprimitive *quad, 
+                            GL2PSprimitive **t1, GL2PSprimitive **t2)
+{
+  *t1 = (GL2PSprimitive*)gl2psMalloc(sizeof(GL2PSprimitive));
+  *t2 = (GL2PSprimitive*)gl2psMalloc(sizeof(GL2PSprimitive));
+  (*t1)->type = (*t2)->type = GL2PS_TRIANGLE;
+  (*t1)->numverts = (*t2)->numverts = 3;
+  (*t1)->culled = (*t2)->culled = quad->culled;
+  (*t1)->offset = (*t2)->offset = quad->offset;
+  (*t1)->pattern = (*t2)->pattern = quad->pattern;
+  (*t1)->factor = (*t2)->factor = quad->factor;
+  (*t1)->width = (*t2)->width = quad->width;
+  (*t1)->verts = (GL2PSvertex*)gl2psMalloc(3 * sizeof(GL2PSvertex));
+  (*t2)->verts = (GL2PSvertex*)gl2psMalloc(3 * sizeof(GL2PSvertex));
+  (*t1)->verts[0] = quad->verts[0];
+  (*t1)->verts[1] = quad->verts[1];
+  (*t1)->verts[2] = quad->verts[2];
+  (*t1)->boundary = ((quad->boundary & 1) ? 1 : 0) | ((quad->boundary & 2) ? 2 : 0);
+  (*t2)->verts[0] = quad->verts[0];
+  (*t2)->verts[1] = quad->verts[2];
+  (*t2)->verts[2] = quad->verts[3];
+  (*t2)->boundary = ((quad->boundary & 4) ? 2 : 0) | ((quad->boundary & 4) ? 2 : 0);
+}
+
+static int gl2psCompareDepth(const void *a, const void *b)
+{
+  GL2PSprimitive *q, *w;
+  GLfloat dq = 0.0F, dw = 0.0F, diff;
+  int i;
+  
+  q = *(GL2PSprimitive**)a;
+  w = *(GL2PSprimitive**)b;
+
+  for(i = 0; i < q->numverts; i++){
+    dq += q->verts[i].xyz[2]; 
+  }
+  dq /= (GLfloat)q->numverts;
+
+  for(i = 0; i < w->numverts; i++){
+    dw += w->verts[i].xyz[2]; 
+  }
+  dw /= (GLfloat)w->numverts;
+
+  diff = dq - dw;
+  if(diff > 0.){
+    return -1;
+  }
+  else if(diff < 0.){
+    return 1;
+  }
+  else{
+    return 0;
+  }
+}
+
+static int gl2psTrianglesFirst(const void *a, const void *b)
+{
+  GL2PSprimitive *q, *w;
+
+  q = *(GL2PSprimitive**)a;
+  w = *(GL2PSprimitive**)b;
+  return(q->type < w->type ? 1 : -1);
+}
+
+static GLint gl2psFindRoot(GL2PSlist *primitives, GL2PSprimitive **root)
+{
+  GLint i, j, count, best = 1000000, index = 0;
+  GL2PSprimitive *prim1, *prim2;
+  GL2PSplane plane;
+  GLint maxp;
+
+  if(!gl2psListNbr(primitives)){
+    gl2psMsg(GL2PS_ERROR, "Cannot fint root in empty primitive list");
+    return 0;
+  }
+
+  *root = *(GL2PSprimitive**)gl2psListPointer(primitives, 0);
+
+  if(gl2ps->options & GL2PS_BEST_ROOT){
+    maxp = gl2psListNbr(primitives);
+    if(maxp > gl2ps->maxbestroot){
+      maxp = gl2ps->maxbestroot;
+    }
+    for(i = 0; i < maxp; i++){
+      prim1 = *(GL2PSprimitive**)gl2psListPointer(primitives, i);
+      gl2psGetPlane(prim1, plane);
+      count = 0;
+      for(j = 0; j < gl2psListNbr(primitives); j++){
+        if(j != i){
+          prim2 = *(GL2PSprimitive**)gl2psListPointer(primitives, j);
+          count += gl2psTestSplitPrimitive(prim2, plane); 
+        }
+        if(count > best) break;
+      }
+      if(count < best){
+        best = count;
+        index = i;
+        *root = prim1;
+        if(!count) return index;
+      }
+    }
+    /* if(index) gl2psMsg(GL2PS_INFO, "GL2PS_BEST_ROOT was worth it: %d", index); */
+    return index;
+  }
+  else{
+    return 0;
+  }
+}
+
+static void gl2psFreeImagemap(GL2PSimagemap *list)
+{
+  GL2PSimagemap *next;
+  while(list != NULL){
+    next = list->next;
+    gl2psFree(list->image->pixels);
+    gl2psFree(list->image);
+    gl2psFree(list);
+    list = next;
+  }
+}
+
+static void gl2psFreePrimitive(void *data)
+{
+  GL2PSprimitive *q;
+  
+  q = *(GL2PSprimitive**)data;
+  gl2psFree(q->verts);
+  if(q->type == GL2PS_TEXT || q->type == GL2PS_SPECIAL){
+    gl2psFreeText(q->data.text);
+  }
+  else if(q->type == GL2PS_PIXMAP){
+    gl2psFreePixmap(q->data.image);
+  }
+  gl2psFree(q);
+}
+
+static void gl2psAddPrimitiveInList(GL2PSprimitive *prim, GL2PSlist *list)
+{
+  GL2PSprimitive *t1, *t2;
+
+  if(prim->type != GL2PS_QUADRANGLE){
+    gl2psListAdd(list, &prim);
+  }
+  else{
+    gl2psDivideQuad(prim, &t1, &t2);
+    gl2psListAdd(list, &t1);
+    gl2psListAdd(list, &t2);
+    gl2psFreePrimitive(&prim);
+  }
+  
+}
+
+static void gl2psFreeBspTree(GL2PSbsptree **tree)
+{
+  if(*tree){
+    if((*tree)->back) gl2psFreeBspTree(&(*tree)->back);
+    if((*tree)->primitives){
+      gl2psListAction((*tree)->primitives, gl2psFreePrimitive);
+      gl2psListDelete((*tree)->primitives);
+    }
+    if((*tree)->front) gl2psFreeBspTree(&(*tree)->front);
+    gl2psFree(*tree);
+    *tree = NULL;
+  }
+}
+
+static GLboolean gl2psGreater(GLfloat f1, GLfloat f2)
+{
+  if(f1 > f2) return GL_TRUE;
+  else return GL_FALSE;
+}
+
+static GLboolean gl2psLess(GLfloat f1, GLfloat f2)
+{
+  if(f1 < f2) return GL_TRUE;
+  else return GL_FALSE;
+}
+
+static void gl2psBuildBspTree(GL2PSbsptree *tree, GL2PSlist *primitives)
+{
+  GL2PSprimitive *prim, *frontprim = NULL, *backprim = NULL;
+  GL2PSlist *frontlist, *backlist;
+  GLint i, index;
+
+  tree->front = NULL;
+  tree->back = NULL;
+  tree->primitives = gl2psListCreate(1, 2, sizeof(GL2PSprimitive*));
+  index = gl2psFindRoot(primitives, &prim);
+  gl2psGetPlane(prim, tree->plane);
+  gl2psAddPrimitiveInList(prim, tree->primitives);
+
+  frontlist = gl2psListCreate(1, 2, sizeof(GL2PSprimitive*));
+  backlist = gl2psListCreate(1, 2, sizeof(GL2PSprimitive*));
+
+  for(i = 0; i < gl2psListNbr(primitives); i++){
+    if(i != index){
+      prim = *(GL2PSprimitive**)gl2psListPointer(primitives,i);
+      switch(gl2psSplitPrimitive(prim, tree->plane, &frontprim, &backprim)){
+      case GL2PS_COINCIDENT:
+        gl2psAddPrimitiveInList(prim, tree->primitives);
+        break;
+      case GL2PS_IN_BACK_OF:
+        gl2psAddPrimitiveInList(prim, backlist);
+        break;
+      case GL2PS_IN_FRONT_OF:
+        gl2psAddPrimitiveInList(prim, frontlist);
+        break;
+      case GL2PS_SPANNING:
+        gl2psAddPrimitiveInList(backprim, backlist);
+        gl2psAddPrimitiveInList(frontprim, frontlist);
+        gl2psFreePrimitive(&prim);
+        break;
+      }
+    }
+  }
+
+  if(gl2psListNbr(tree->primitives)){
+    gl2psListSort(tree->primitives, gl2psTrianglesFirst);
+  }
+
+  if(gl2psListNbr(frontlist)){
+    gl2psListSort(frontlist, gl2psTrianglesFirst);
+    tree->front = (GL2PSbsptree*)gl2psMalloc(sizeof(GL2PSbsptree));
+    gl2psBuildBspTree(tree->front, frontlist);
+  }
+  else{
+    gl2psListDelete(frontlist);
+  }
+
+  if(gl2psListNbr(backlist)){
+    gl2psListSort(backlist, gl2psTrianglesFirst);
+    tree->back = (GL2PSbsptree*)gl2psMalloc(sizeof(GL2PSbsptree));
+    gl2psBuildBspTree(tree->back, backlist);
+  }
+  else{
+    gl2psListDelete(backlist);
+  }
+
+  gl2psListDelete(primitives);
+}
+
+static void gl2psTraverseBspTree(GL2PSbsptree *tree, GL2PSxyz eye, GLfloat epsilon,
+                                 GLboolean (*compare)(GLfloat f1, GLfloat f2),
+                                 void (*action)(void *data), int inverse)
+{
+  GLfloat result;
+
+  if(!tree) return;
+
+  result = gl2psComparePointPlane(eye, tree->plane);
+
+  if(GL_TRUE == compare(result, epsilon)){
+    gl2psTraverseBspTree(tree->back, eye, epsilon, compare, action, inverse);
+    if(inverse){
+      gl2psListActionInverse(tree->primitives, action);
+    }
+    else{
+      gl2psListAction(tree->primitives, action);
+    }
+    gl2psTraverseBspTree(tree->front, eye, epsilon, compare, action, inverse);
+  }
+  else if(GL_TRUE == compare(-epsilon, result)){ 
+    gl2psTraverseBspTree(tree->front, eye, epsilon, compare, action, inverse);
+    if(inverse){
+      gl2psListActionInverse(tree->primitives, action);
+    }
+    else{
+      gl2psListAction(tree->primitives, action);
+    }
+    gl2psTraverseBspTree(tree->back, eye, epsilon, compare, action, inverse);
+  }
+  else{
+    gl2psTraverseBspTree(tree->front, eye, epsilon, compare, action, inverse);
+    gl2psTraverseBspTree(tree->back, eye, epsilon, compare, action, inverse);
+  }
+}
+
+static void gl2psRescaleAndOffset()
+{
+  GL2PSprimitive *prim;
+  GLfloat minZ, maxZ, rangeZ, scaleZ;
+  GLfloat factor, units, area, dZ, dZdX, dZdY, maxdZ;
+  int i, j;
+
+  if(!gl2psListNbr(gl2ps->primitives))
+    return;
+
+  /* get z-buffer range */
+  prim = *(GL2PSprimitive**)gl2psListPointer(gl2ps->primitives, 0);
+  minZ = maxZ = prim->verts[0].xyz[2];
+  for(i = 1; i < prim->numverts; i++){
+    if(prim->verts[i].xyz[2] < minZ) minZ = prim->verts[i].xyz[2];
+    if(prim->verts[i].xyz[2] > maxZ) maxZ = prim->verts[i].xyz[2];
+  }
+  for(i = 1; i < gl2psListNbr(gl2ps->primitives); i++){
+    prim = *(GL2PSprimitive**)gl2psListPointer(gl2ps->primitives, i);
+    for(j = 0; j < prim->numverts; j++){
+      if(prim->verts[j].xyz[2] < minZ) minZ = prim->verts[j].xyz[2];
+      if(prim->verts[j].xyz[2] > maxZ) maxZ = prim->verts[j].xyz[2];
+    }
+  }
+  rangeZ = (maxZ - minZ);
+
+  /* rescale z-buffer coordinate in [0,GL2PS_ZSCALE], to make it of
+     the same order of magnitude as the x and y coordinates */
+  scaleZ = GL2PS_ZERO(rangeZ) ? GL2PS_ZSCALE : (GL2PS_ZSCALE / rangeZ);
+  /* avoid precision loss (we use floats!) */
+  if(scaleZ > 100000.F) scaleZ = 100000.F;
+
+  /* apply offsets */
+  for(i = 0; i < gl2psListNbr(gl2ps->primitives); i++){
+    prim = *(GL2PSprimitive**)gl2psListPointer(gl2ps->primitives, i);
+    for(j = 0; j < prim->numverts; j++){
+      prim->verts[j].xyz[2] = (prim->verts[j].xyz[2] - minZ) * scaleZ;
+    }
+    if((gl2ps->options & GL2PS_SIMPLE_LINE_OFFSET) &&
+       (prim->type == GL2PS_LINE)){
+      if(gl2ps->sort == GL2PS_SIMPLE_SORT){
+        prim->verts[0].xyz[2] -= GL2PS_ZOFFSET_LARGE;
+        prim->verts[1].xyz[2] -= GL2PS_ZOFFSET_LARGE;
+      }
+      else{
+        prim->verts[0].xyz[2] -= GL2PS_ZOFFSET;
+        prim->verts[1].xyz[2] -= GL2PS_ZOFFSET;
+      }
+    }
+    else if(prim->offset && (prim->type == GL2PS_TRIANGLE)){
+      factor = gl2ps->offset[0];
+      units = gl2ps->offset[1];
+      area = 
+        (prim->verts[1].xyz[0] - prim->verts[0].xyz[0]) * 
+        (prim->verts[2].xyz[1] - prim->verts[1].xyz[1]) - 
+        (prim->verts[2].xyz[0] - prim->verts[1].xyz[0]) * 
+        (prim->verts[1].xyz[1] - prim->verts[0].xyz[1]);
+      if(!GL2PS_ZERO(area)){
+        dZdX = 
+          ((prim->verts[2].xyz[1] - prim->verts[1].xyz[1]) *
+           (prim->verts[1].xyz[2] - prim->verts[0].xyz[2]) -
+           (prim->verts[1].xyz[1] - prim->verts[0].xyz[1]) *
+           (prim->verts[2].xyz[2] - prim->verts[1].xyz[2])) / area;
+        dZdY = 
+          ((prim->verts[1].xyz[0] - prim->verts[0].xyz[0]) *
+           (prim->verts[2].xyz[2] - prim->verts[1].xyz[2]) -
+           (prim->verts[2].xyz[0] - prim->verts[1].xyz[0]) *
+           (prim->verts[1].xyz[2] - prim->verts[0].xyz[2])) / area;
+        maxdZ = (GLfloat)sqrt(dZdX * dZdX + dZdY * dZdY);
+      }
+      else{
+        maxdZ = 0.0F;
+      }
+      dZ = factor * maxdZ + units;
+      prim->verts[0].xyz[2] += dZ;
+      prim->verts[1].xyz[2] += dZ;
+      prim->verts[2].xyz[2] += dZ;
+    }
+  }
+}
+
+/********************************************************************* 
+ *
+ * 2D sorting routines (for occlusion culling) 
+ *
+ *********************************************************************/
+
+static GLint gl2psGetPlaneFromPoints(GL2PSxyz a, GL2PSxyz b, GL2PSplane plane)
+{
+  GLfloat n; 
+
+  plane[0] = b[1] - a[1];
+  plane[1] = a[0] - b[0];
+  n = (GLfloat)sqrt(plane[0]*plane[0] + plane[1]*plane[1]);
+  plane[2] = 0.0F;
+  if(!GL2PS_ZERO(n)){
+    plane[0] /= n;
+    plane[1] /= n;
+    plane[3] = -plane[0]*a[0]-plane[1]*a[1]; 
+    return 1;
+  }
+  else{
+    plane[0] = -1.0F;
+    plane[1] = 0.0F;
+    plane[3] = a[0];
+    return 0;
+  }
+}
+
+static void gl2psFreeBspImageTree(GL2PSbsptree2d **tree)
+{
+  if(*tree){
+    if((*tree)->back)  gl2psFreeBspImageTree(&(*tree)->back);
+    if((*tree)->front) gl2psFreeBspImageTree(&(*tree)->front);
+    gl2psFree(*tree);
+    *tree = NULL;
+  }
+}
+
+static GLint gl2psCheckPoint(GL2PSxyz point, GL2PSplane plane)
+{
+  GLfloat pt_dis;
+
+  pt_dis = gl2psComparePointPlane(point, plane);
+  if(pt_dis > GL2PS_EPSILON)        return GL2PS_POINT_INFRONT;
+  else if(pt_dis < -GL2PS_EPSILON)  return GL2PS_POINT_BACK;
+  else                              return GL2PS_POINT_COINCIDENT;
+}
+
+static void gl2psAddPlanesInBspTreeImage(GL2PSprimitive *prim,
+                                         GL2PSbsptree2d **tree)
+{
+  GLint ret = 0;
+  GLint i;
+  GLint offset = 0;
+  GL2PSbsptree2d *head = NULL, *cur = NULL;
+
+  if((*tree == NULL) && (prim->numverts > 2)){
+    /* don't cull if transparent
+    for(i = 0; i < prim->numverts - 1; i++)
+      if(prim->verts[i].rgba[3] < 1.0F) return;
+    */
+    head = (GL2PSbsptree2d*)gl2psMalloc(sizeof(GL2PSbsptree2d));
+    for(i = 0; i < prim->numverts-1; i++){
+      if(!gl2psGetPlaneFromPoints(prim->verts[i].xyz,
+                                  prim->verts[i+1].xyz,
+                                  head->plane)){
+        if(prim->numverts-i > 3){
+          offset++;
+        }
+        else{
+          gl2psFree(head);
+          return;
+        }
+      }
+      else{
+        break;
+      }
+    }
+    head->back = NULL;
+    head->front = NULL;
+    for(i = 2+offset; i < prim->numverts; i++){
+      ret = gl2psCheckPoint(prim->verts[i].xyz, head->plane);
+      if(ret != GL2PS_POINT_COINCIDENT) break;
+    }
+    switch(ret){
+    case GL2PS_POINT_INFRONT :
+      cur = head;
+      for(i = 1+offset; i < prim->numverts-1; i++){
+        if(cur->front == NULL){
+          cur->front = (GL2PSbsptree2d*)gl2psMalloc(sizeof(GL2PSbsptree2d));
+        }
+        if(gl2psGetPlaneFromPoints(prim->verts[i].xyz,
+                                   prim->verts[i+1].xyz,
+                                   cur->front->plane)){
+          cur = cur->front;
+          cur->front = NULL;
+          cur->back = NULL;
+        }
+      }
+      if(cur->front == NULL){
+        cur->front = (GL2PSbsptree2d*)gl2psMalloc(sizeof(GL2PSbsptree2d));
+      }
+      if(gl2psGetPlaneFromPoints(prim->verts[i].xyz,
+                                 prim->verts[offset].xyz,
+                                 cur->front->plane)){
+        cur->front->front = NULL;
+        cur->front->back = NULL;
+      }
+      else{
+        gl2psFree(cur->front);
+        cur->front = NULL;
+      }
+      break;
+    case GL2PS_POINT_BACK :
+      for(i = 0; i < 4; i++){
+        head->plane[i] = -head->plane[i];
+      }
+      cur = head;
+      for(i = 1+offset; i < prim->numverts-1; i++){
+        if(cur->front == NULL){
+          cur->front = (GL2PSbsptree2d*)gl2psMalloc(sizeof(GL2PSbsptree2d));
+        }
+        if(gl2psGetPlaneFromPoints(prim->verts[i+1].xyz,
+                                   prim->verts[i].xyz,
+                                   cur->front->plane)){
+          cur = cur->front;
+          cur->front = NULL;
+          cur->back = NULL;
+        }
+      }
+      if(cur->front == NULL){
+        cur->front = (GL2PSbsptree2d*)gl2psMalloc(sizeof(GL2PSbsptree2d));
+      }
+      if(gl2psGetPlaneFromPoints(prim->verts[offset].xyz,
+                                 prim->verts[i].xyz,
+                                 cur->front->plane)){
+        cur->front->front = NULL;
+        cur->front->back = NULL;
+      }
+      else{
+        gl2psFree(cur->front);
+        cur->front = NULL;
+      }
+      break;
+    default:
+      gl2psFree(head);
+      return;
+    }
+    (*tree) = head;
+  }
+}
+
+static GLint gl2psCheckPrimitive(GL2PSprimitive *prim, GL2PSplane plane)
+{
+  GLint i;
+  GLint pos;
+
+  pos = gl2psCheckPoint(prim->verts[0].xyz, plane);
+  for(i = 1; i < prim->numverts; i++){
+    pos |= gl2psCheckPoint(prim->verts[i].xyz, plane);
+    if(pos == (GL2PS_POINT_INFRONT | GL2PS_POINT_BACK)) return GL2PS_SPANNING;
+  }
+  if(pos & GL2PS_POINT_INFRONT)   return GL2PS_IN_FRONT_OF;
+  else if(pos & GL2PS_POINT_BACK) return GL2PS_IN_BACK_OF;
+  else                            return GL2PS_COINCIDENT;
+}
+
+static GL2PSprimitive *gl2psCreateSplitPrimitive2D(GL2PSprimitive *parent,
+                                                   GLshort numverts,
+                                                   GL2PSvertex *vertx)
+{
+  GLint i;
+  GL2PSprimitive *child = (GL2PSprimitive*)gl2psMalloc(sizeof(GL2PSprimitive));
+
+  if(parent->type == GL2PS_IMAGEMAP){
+    child->type = GL2PS_IMAGEMAP;
+    child->data.image = parent->data.image;
+  }
+  else {
+    switch(numverts){
+    case 1 : child->type = GL2PS_POINT; break;
+    case 2 : child->type = GL2PS_LINE; break;
+    case 3 : child->type = GL2PS_TRIANGLE; break;
+    case 4 : child->type = GL2PS_QUADRANGLE; break;
+    default: child->type = GL2PS_NO_TYPE; break; /* FIXME */
+    }
+  }
+  child->boundary = 0; /* FIXME: not done! */
+  child->culled = parent->culled;
+  child->offset = parent->offset;
+  child->pattern = parent->pattern;
+  child->factor = parent->factor;
+  child->width = parent->width;
+  child->numverts = numverts;
+  child->verts = (GL2PSvertex*)gl2psMalloc(numverts * sizeof(GL2PSvertex));
+  for(i = 0; i < numverts; i++){
+    child->verts[i] = vertx[i];
+  }
+  return child;
+}
+
+static void gl2psSplitPrimitive2D(GL2PSprimitive *prim,
+                                  GL2PSplane plane, 
+                                  GL2PSprimitive **front, 
+                                  GL2PSprimitive **back)
+{
+  /* cur will hold the position of the current vertex
+     prev will hold the position of the previous vertex
+     prev0 will hold the position of the vertex number 0
+     v1 and v2 represent the current and previous vertices, respectively
+     flag is set if the current vertex should be checked against the plane */
+  GLint cur = -1, prev = -1, i, v1 = 0, v2 = 0, flag = 1, prev0 = -1;
+  
+  /* list of vertices that will go in front and back primitive */
+  GL2PSvertex *front_list = NULL, *back_list = NULL;
+  
+  /* number of vertices in front and back list */
+  GLshort front_count = 0, back_count = 0;
+
+  for(i = 0; i <= prim->numverts; i++){
+    v1 = i;
+    if(v1 == prim->numverts){
+      if(prim->numverts < 3) break;
+      v1 = 0;
+      v2 = prim->numverts - 1;
+      cur = prev0;
+    }
+    else if(flag){
+      cur = gl2psCheckPoint(prim->verts[v1].xyz, plane);
+      if(i == 0){
+        prev0 = cur;
+      }
+    } 
+    if(((prev == -1) || (prev == cur) || (prev == 0) || (cur == 0)) &&
+       (i < prim->numverts)){
+      if(cur == GL2PS_POINT_INFRONT){
+        front_count++;
+        front_list = (GL2PSvertex*)gl2psRealloc(front_list,
+                                                sizeof(GL2PSvertex)*front_count);
+        front_list[front_count-1] = prim->verts[v1];
+      }
+      else if(cur == GL2PS_POINT_BACK){
+        back_count++;
+        back_list = (GL2PSvertex*)gl2psRealloc(back_list,
+                                               sizeof(GL2PSvertex)*back_count);
+        back_list[back_count-1] = prim->verts[v1];
+      }
+      else{
+        front_count++;
+        front_list = (GL2PSvertex*)gl2psRealloc(front_list,
+                                                sizeof(GL2PSvertex)*front_count);
+        front_list[front_count-1] = prim->verts[v1];
+        back_count++;
+        back_list = (GL2PSvertex*)gl2psRealloc(back_list,
+                                               sizeof(GL2PSvertex)*back_count);
+        back_list[back_count-1] = prim->verts[v1];
+      }
+      flag = 1;
+    }
+    else if((prev != cur) && (cur != 0) && (prev != 0)){
+      if(v1 != 0){
+        v2 = v1-1;
+        i--;
+      }
+      front_count++;
+      front_list = (GL2PSvertex*)gl2psRealloc(front_list,
+                                              sizeof(GL2PSvertex)*front_count);
+      gl2psCutEdge(&prim->verts[v2], &prim->verts[v1],
+                   plane, &front_list[front_count-1]);
+      back_count++;
+      back_list = (GL2PSvertex*)gl2psRealloc(back_list,
+                                             sizeof(GL2PSvertex)*back_count);
+      back_list[back_count-1] = front_list[front_count-1];
+      flag = 0;
+    }
+    prev = cur;
+  }
+  *front = gl2psCreateSplitPrimitive2D(prim, front_count, front_list);
+  *back = gl2psCreateSplitPrimitive2D(prim, back_count, back_list);
+  gl2psFree(front_list);
+  gl2psFree(back_list);
+}
+
+static GLint gl2psAddInBspImageTree(GL2PSprimitive *prim, GL2PSbsptree2d **tree)
+{
+  GLint ret = 0;
+  GL2PSprimitive *frontprim = NULL, *backprim = NULL;
+  
+  /* FIXME: until we consider the actual extent of text strings and
+     pixmaps, never cull them. Otherwise the whole string/pixmap gets
+     culled as soon as the reference point is hidden */
+  if(prim->type == GL2PS_PIXMAP || 
+     prim->type == GL2PS_TEXT || 
+     prim->type == GL2PS_SPECIAL){
+    return 1;
+  }
+
+  if(*tree == NULL){
+    if((prim->type != GL2PS_IMAGEMAP) && (GL_FALSE == gl2ps->zerosurfacearea)){
+      gl2psAddPlanesInBspTreeImage(gl2ps->primitivetoadd, tree);
+    }
+    return 1;
+  }
+  else{
+    switch(gl2psCheckPrimitive(prim, (*tree)->plane)){
+    case GL2PS_IN_BACK_OF: return gl2psAddInBspImageTree(prim, &(*tree)->back);
+    case GL2PS_IN_FRONT_OF: 
+      if((*tree)->front != NULL) return gl2psAddInBspImageTree(prim, &(*tree)->front);
+      else                       return 0;
+    case GL2PS_SPANNING:
+      gl2psSplitPrimitive2D(prim, (*tree)->plane, &frontprim, &backprim);
+      ret = gl2psAddInBspImageTree(backprim, &(*tree)->back);
+      if((*tree)->front != NULL){
+        if(gl2psAddInBspImageTree(frontprim, &(*tree)->front)){
+          ret = 1;
+        }
+      }
+      gl2psFree(frontprim->verts);
+      gl2psFree(frontprim);
+      gl2psFree(backprim->verts);
+      gl2psFree(backprim);
+      return ret;
+    case GL2PS_COINCIDENT:
+      if((*tree)->back != NULL){
+        gl2ps->zerosurfacearea = GL_TRUE;
+        ret = gl2psAddInBspImageTree(prim, &(*tree)->back);
+        gl2ps->zerosurfacearea = GL_FALSE;
+        if(ret) return ret;
+      }
+      if((*tree)->front != NULL){
+        gl2ps->zerosurfacearea = GL_TRUE;
+        ret = gl2psAddInBspImageTree(prim, &(*tree)->front);
+        gl2ps->zerosurfacearea = GL_FALSE;
+        if(ret) return ret;
+      }
+      if(prim->type == GL2PS_LINE) return 1;
+      else                         return 0;
+    }
+  }
+  return 0;
+}
+
+static void gl2psAddInImageTree(void *data)
+{
+  GL2PSprimitive *prim = *(GL2PSprimitive **)data;
+  gl2ps->primitivetoadd = prim;
+  if(prim->type == GL2PS_IMAGEMAP && prim->data.image->format == GL2PS_IMAGEMAP_VISIBLE){
+    prim->culled = 1;
+  }
+  else if(!gl2psAddInBspImageTree(prim, &gl2ps->imagetree)){
+    prim->culled = 1;
+  }
+  else if(prim->type == GL2PS_IMAGEMAP){
+    prim->data.image->format = GL2PS_IMAGEMAP_VISIBLE;
+  }
+}
+
+/* Boundary construction */
+
+static void gl2psAddBoundaryInList(GL2PSprimitive *prim, GL2PSlist *list)
+{
+  GL2PSprimitive *b;
+  GLshort i;
+  GL2PSxyz c;
+
+  c[0] = c[1] = c[2] = 0.0F;
+  for(i = 0; i < prim->numverts; i++){
+    c[0] += prim->verts[i].xyz[0];
+    c[1] += prim->verts[i].xyz[1];
+  }
+  c[0] /= prim->numverts;
+  c[1] /= prim->numverts;
+
+  for(i = 0; i < prim->numverts; i++){
+    if(prim->boundary & (GLint)pow(2., i)){
+      b = (GL2PSprimitive*)gl2psMalloc(sizeof(GL2PSprimitive));
+      b->type = GL2PS_LINE;
+      b->offset = prim->offset;
+      b->pattern = prim->pattern;
+      b->factor = prim->factor;
+      b->culled = prim->culled;
+      b->width = prim->width;
+      b->boundary = 0;
+      b->numverts = 2;
+      b->verts = (GL2PSvertex*)gl2psMalloc(2 * sizeof(GL2PSvertex));
+
+#if 0 /* FIXME: need to work on boundary offset... */
+      v[0] = c[0] - prim->verts[i].xyz[0];
+      v[1] = c[1] - prim->verts[i].xyz[1];
+      v[2] = 0.0F;
+      norm = gl2psNorm(v);
+      v[0] /= norm;
+      v[1] /= norm;
+      b->verts[0].xyz[0] = prim->verts[i].xyz[0] +0.1*v[0];
+      b->verts[0].xyz[1] = prim->verts[i].xyz[1] +0.1*v[1];
+      b->verts[0].xyz[2] = prim->verts[i].xyz[2];
+      v[0] = c[0] - prim->verts[gl2psGetIndex(i, prim->numverts)].xyz[0];
+      v[1] = c[1] - prim->verts[gl2psGetIndex(i, prim->numverts)].xyz[1];
+      norm = gl2psNorm(v);
+      v[0] /= norm;
+      v[1] /= norm;
+      b->verts[1].xyz[0] = prim->verts[gl2psGetIndex(i, prim->numverts)].xyz[0] +0.1*v[0];
+      b->verts[1].xyz[1] = prim->verts[gl2psGetIndex(i, prim->numverts)].xyz[1] +0.1*v[1];
+      b->verts[1].xyz[2] = prim->verts[gl2psGetIndex(i, prim->numverts)].xyz[2];
+#else
+      b->verts[0].xyz[0] = prim->verts[i].xyz[0];
+      b->verts[0].xyz[1] = prim->verts[i].xyz[1];
+      b->verts[0].xyz[2] = prim->verts[i].xyz[2];
+      b->verts[1].xyz[0] = prim->verts[gl2psGetIndex(i, prim->numverts)].xyz[0];
+      b->verts[1].xyz[1] = prim->verts[gl2psGetIndex(i, prim->numverts)].xyz[1];
+      b->verts[1].xyz[2] = prim->verts[gl2psGetIndex(i, prim->numverts)].xyz[2];
+#endif
+
+      b->verts[0].rgba[0] = 0.0F;
+      b->verts[0].rgba[1] = 0.0F;
+      b->verts[0].rgba[2] = 0.0F;
+      b->verts[0].rgba[3] = 0.0F;
+      b->verts[1].rgba[0] = 0.0F;
+      b->verts[1].rgba[1] = 0.0F;
+      b->verts[1].rgba[2] = 0.0F;
+      b->verts[1].rgba[3] = 0.0F;
+      gl2psListAdd(list, &b);
+    }
+  }
+
+}
+
+static void gl2psBuildPolygonBoundary(GL2PSbsptree *tree)
+{
+  GLint i;
+  GL2PSprimitive *prim;
+
+  if(!tree) return;
+  gl2psBuildPolygonBoundary(tree->back);
+  for(i = 0; i < gl2psListNbr(tree->primitives); i++){
+    prim = *(GL2PSprimitive**)gl2psListPointer(tree->primitives, i);
+    if(prim->boundary) gl2psAddBoundaryInList(prim, tree->primitives);
+  }
+  gl2psBuildPolygonBoundary(tree->front);
+}
+
+/********************************************************************* 
+ *
+ * Feedback buffer parser
+ *
+ *********************************************************************/
+
+static void gl2psAddPolyPrimitive(GLshort type, GLshort numverts, 
+                                  GL2PSvertex *verts, GLint offset, 
+                                  GLushort pattern, GLint factor,
+                                  GLfloat width, char boundary)
+{
+  GL2PSprimitive *prim;
+
+  prim = (GL2PSprimitive*)gl2psMalloc(sizeof(GL2PSprimitive));
+  prim->type = type;
+  prim->numverts = numverts;
+  prim->verts = (GL2PSvertex*)gl2psMalloc(numverts * sizeof(GL2PSvertex));
+  memcpy(prim->verts, verts, numverts * sizeof(GL2PSvertex));
+  prim->boundary = boundary;
+  prim->offset = offset;
+  prim->pattern = pattern;
+  prim->factor = factor;
+  prim->width = width;
+  prim->culled = 0;
+
+  /* FIXME: here we should have an option to split stretched
+     tris/quads to enhance SIMPLE_SORT */
+
+  gl2psListAdd(gl2ps->primitives, &prim);
+}
+
+static GLint gl2psGetVertex(GL2PSvertex *v, GLfloat *p)
+{
+  GLint i;
+
+  v->xyz[0] = p[0];
+  v->xyz[1] = p[1];
+  v->xyz[2] = p[2];
+
+  if(gl2ps->colormode == GL_COLOR_INDEX && gl2ps->colorsize > 0){
+    i = (GLint)(p[3] + 0.5);
+    v->rgba[0] = gl2ps->colormap[i][0];
+    v->rgba[1] = gl2ps->colormap[i][1];
+    v->rgba[2] = gl2ps->colormap[i][2];
+    v->rgba[3] = gl2ps->colormap[i][3];
+    return 4;
+  }
+  else{
+    v->rgba[0] = p[3];
+    v->rgba[1] = p[4];
+    v->rgba[2] = p[5];
+    v->rgba[3] = p[6];
+    return 7;
+  }
+}
+
+static void gl2psParseFeedbackBuffer(GLint used)
+{
+  char flag;
+  GLushort pattern = 0;
+  GLboolean boundary;
+  GLint i, sizeoffloat, count, v, vtot, offset = 0, factor = 0, auxindex = 0;
+  GLfloat lwidth = 1.0F, psize = 1.0F;
+  GLfloat *current;
+  GL2PSvertex vertices[3];
+  GL2PSprimitive *prim;
+  GL2PSimagemap *node;
+
+  current = gl2ps->feedback;
+  boundary = gl2ps->boundary = GL_FALSE;
+
+  while(used > 0){
+
+    if(GL_TRUE == boundary) gl2ps->boundary = GL_TRUE;
+    
+    switch((GLint)*current){
+    case GL_POINT_TOKEN :
+      current ++;
+      used --;
+      i = gl2psGetVertex(&vertices[0], current);
+      current += i;
+      used    -= i;
+      gl2psAddPolyPrimitive(GL2PS_POINT, 1, vertices, 0, 
+                            pattern, factor, psize, 0);
+      break;
+    case GL_LINE_TOKEN :
+    case GL_LINE_RESET_TOKEN :
+      current ++;
+      used --;
+      i = gl2psGetVertex(&vertices[0], current);
+      current += i;
+      used    -= i;
+      i = gl2psGetVertex(&vertices[1], current);
+      current += i;
+      used    -= i;
+      gl2psAddPolyPrimitive(GL2PS_LINE, 2, vertices, 0, 
+                            pattern, factor, lwidth, 0);
+      break;
+    case GL_POLYGON_TOKEN :
+      count = (GLint)current[1];
+      current += 2;
+      used -= 2;
+      v = vtot = 0;
+      while(count > 0 && used > 0){
+        i = gl2psGetVertex(&vertices[v], current);
+        gl2psAdaptVertexForBlending(&vertices[v]);
+        current += i;
+        used    -= i;
+        count --;
+        vtot++;
+        if(v == 2){
+          if(GL_TRUE == boundary){
+            if(!count && vtot == 2) flag = 1|2|4;
+            else if(!count) flag = 2|4;
+            else if(vtot == 2) flag = 1|2;
+            else flag = 2;
+          }
+          else
+            flag = 0;
+          gl2psAddPolyPrimitive(GL2PS_TRIANGLE, 3, vertices, offset,
+                                pattern, factor, 1, flag);
+          vertices[1] = vertices[2];
+        }
+        else
+          v ++;
+      }
+      break;      
+    case GL_BITMAP_TOKEN :
+    case GL_DRAW_PIXEL_TOKEN :
+    case GL_COPY_PIXEL_TOKEN :
+      current ++;
+      used --;
+      i = gl2psGetVertex(&vertices[0], current);
+      current += i;
+      used    -= i;
+      break;      
+    case GL_PASS_THROUGH_TOKEN :
+      switch((GLint)current[1]){
+      case GL2PS_BEGIN_OFFSET_TOKEN : offset = 1; break;
+      case GL2PS_END_OFFSET_TOKEN : offset = 0; break;
+      case GL2PS_BEGIN_BOUNDARY_TOKEN : boundary = GL_TRUE; break;
+      case GL2PS_END_BOUNDARY_TOKEN : boundary = GL_FALSE; break;
+      case GL2PS_END_STIPPLE_TOKEN : pattern = factor = 0; break;
+      case GL2PS_BEGIN_BLEND_TOKEN : gl2ps->blending = GL_TRUE; break;
+      case GL2PS_END_BLEND_TOKEN : gl2ps->blending = GL_FALSE; break;
+      case GL2PS_BEGIN_STIPPLE_TOKEN : 
+        current += 2;
+        used -= 2; 
+        pattern = (GLushort)current[1]; 
+        current += 2;
+        used -= 2; 
+        factor = (GLint)current[1]; 
+        break;
+      case GL2PS_SRC_BLEND_TOKEN : 
+        current += 2; 
+        used -= 2; 
+        gl2ps->blendfunc[0] = (GLint)current[1];
+        break;
+      case GL2PS_DST_BLEND_TOKEN : 
+        current += 2; 
+        used -= 2; 
+        gl2ps->blendfunc[1] = (GLint)current[1];
+        break;
+      case GL2PS_POINT_SIZE_TOKEN : 
+        current += 2; 
+        used -= 2; 
+        psize = current[1];
+        break;
+      case GL2PS_LINE_WIDTH_TOKEN : 
+        current += 2; 
+        used -= 2; 
+        lwidth = current[1];
+        break;
+      case GL2PS_IMAGEMAP_TOKEN :
+        prim = (GL2PSprimitive *)gl2psMalloc(sizeof(GL2PSprimitive));
+        prim->type = GL2PS_IMAGEMAP;
+        prim->boundary = 0;
+        prim->numverts = 4;
+        prim->verts = (GL2PSvertex *)gl2psMalloc(4 * sizeof(GL2PSvertex));
+        prim->culled = 0;
+        prim->offset = 0;
+        prim->pattern = 0;
+        prim->factor = 0;
+        prim->width = 1;
+        
+        node = (GL2PSimagemap*)gl2psMalloc(sizeof(GL2PSimagemap));
+        node->image = (GL2PSimage*)gl2psMalloc(sizeof(GL2PSimage));
+        node->image->type = 0;
+        node->image->format = 0;
+        node->next = NULL;
+        
+        if(gl2ps->imagemap_head == NULL)
+          gl2ps->imagemap_head = node;
+        else
+          gl2ps->imagemap_tail->next = node;
+        gl2ps->imagemap_tail = node;
+        prim->data.image = node->image;
+        
+        current += 2; used -= 2;
+        i = gl2psGetVertex(&prim->verts[0], &current[1]);
+        current += i; used -= i;
+        
+        node->image->width = (GLint)current[2];
+        current += 2; used -= 2;
+        node->image->height = (GLint)current[2];
+        prim->verts[0].xyz[0] = prim->verts[0].xyz[0] - (int)(node->image->width / 2) + 0.5F;
+        prim->verts[0].xyz[1] = prim->verts[0].xyz[1] - (int)(node->image->height / 2) + 0.5F;
+        for(i = 1; i < 4; i++){
+          for(v = 0; v < 3; v++){
+            prim->verts[i].xyz[v] = prim->verts[0].xyz[v];
+            prim->verts[i].rgba[v] = prim->verts[0].rgba[v];
+          }
+          prim->verts[i].rgba[v] = prim->verts[0].rgba[v];
+        }
+        prim->verts[1].xyz[0] = prim->verts[1].xyz[0] + node->image->width;
+        prim->verts[2].xyz[0] = prim->verts[1].xyz[0];
+        prim->verts[2].xyz[1] = prim->verts[2].xyz[1] + node->image->height;
+        prim->verts[3].xyz[1] = prim->verts[2].xyz[1];
+
+        sizeoffloat = sizeof(GLfloat);
+        v = 2 * sizeoffloat;
+        vtot = node->image->height + node->image->height * 
+          ((node->image->width - 1) / 8);
+        node->image->pixels = (GLfloat*)gl2psMalloc(v + vtot);
+        node->image->pixels[0] = prim->verts[0].xyz[0];
+        node->image->pixels[1] = prim->verts[0].xyz[1];
+        
+        for(i = 0; i < vtot; i += sizeoffloat){
+          current += 2; used -= 2;
+          if((vtot - i) >= 4)
+            memcpy(&(((char*)(node->image->pixels))[i + v]), &(current[2]), sizeoffloat);
+          else
+            memcpy(&(((char*)(node->image->pixels))[i + v]), &(current[2]), vtot - i);
+        }
+        current++; used--;
+        gl2psListAdd(gl2ps->primitives, &prim);
+        break;
+      case GL2PS_DRAW_PIXELS_TOKEN :
+      case GL2PS_TEXT_TOKEN :
+        if(auxindex < gl2psListNbr(gl2ps->auxprimitives))
+          gl2psListAdd(gl2ps->primitives, 
+                       gl2psListPointer(gl2ps->auxprimitives, auxindex++));
+        else
+          gl2psMsg(GL2PS_ERROR, "Wrong number of auxiliary tokens in buffer");
+        break;
+      }
+      current += 2; 
+      used -= 2; 
+      break;      
+    default :
+      gl2psMsg(GL2PS_WARNING, "Unknown token in buffer");
+      current ++;
+      used --;
+      break;
+    }
+  }
+
+  gl2psListReset(gl2ps->auxprimitives);
+}
+
+/********************************************************************* 
+ *
+ * PostScript routines
+ *
+ *********************************************************************/
+
+static void gl2psWriteByte(unsigned char byte)
+{
+  unsigned char h = byte / 16;
+  unsigned char l = byte % 16;
+  gl2psPrintf("%x%x", h, l);
+}
+
+static void gl2psPrintPostScriptPixmap(GLfloat x, GLfloat y, GL2PSimage *im)
+{
+  GLuint nbhex, nbyte, nrgb, nbits;
+  GLuint row, col, ibyte, icase;
+  GLfloat dr, dg, db, fgrey;
+  unsigned char red = 0, green = 0, blue = 0, b, grey;
+  GLuint width = (GLuint)im->width;
+  GLuint height = (GLuint)im->height;
+
+  /* FIXME: should we define an option for these? Or just keep the
+     8-bit per component case? */
+  int greyscale = 0; /* set to 1 to output greyscale image */
+  int nbit = 8; /* number of bits per color compoment (2, 4 or 8) */
+
+  if((width <= 0) || (height <= 0)) return;
+
+  gl2psPrintf("gsave\n");
+  gl2psPrintf("%.2f %.2f translate\n", x, y); 
+  gl2psPrintf("%d %d scale\n", width, height); 
+
+  if(greyscale){ /* greyscale */
+    gl2psPrintf("/picstr %d string def\n", width); 
+    gl2psPrintf("%d %d %d\n", width, height, 8); 
+    gl2psPrintf("[ %d 0 0 -%d 0 %d ]\n", width, height, height); 
+    gl2psPrintf("{ currentfile picstr readhexstring pop }\n");
+    gl2psPrintf("image\n");
+    for(row = 0; row < height; row++){
+      for(col = 0; col < width; col++){ 
+        gl2psGetRGB(im, col, row, &dr, &dg, &db);
+        fgrey = (0.30F * dr + 0.59F * dg + 0.11F * db);
+        grey = (unsigned char)(255. * fgrey);
+        gl2psWriteByte(grey);
+      }
+      gl2psPrintf("\n");
+    }
+    nbhex = width * height * 2; 
+    gl2psPrintf("%%%% nbhex digit          :%d\n", nbhex); 
+  }
+  else if(nbit == 2){ /* color, 2 bits for r and g and b; rgbs following each other */
+    nrgb = width  * 3;
+    nbits = nrgb * nbit;
+    nbyte = nbits / 8;
+    if((nbyte * 8) != nbits) nbyte++;
+    gl2psPrintf("/rgbstr %d string def\n", nbyte);
+    gl2psPrintf("%d %d %d\n", width, height, nbit);
+    gl2psPrintf("[ %d 0 0 -%d 0 %d ]\n", width, height, height);
+    gl2psPrintf("{ currentfile rgbstr readhexstring pop }\n");
+    gl2psPrintf("false 3\n");
+    gl2psPrintf("colorimage\n");
+    for(row = 0; row < height; row++){
+      icase = 1;
+      col = 0;
+      b = 0;
+      for(ibyte = 0; ibyte < nbyte; ibyte++){
+        if(icase == 1) {
+          if(col < width) {
+            gl2psGetRGB(im, col, row, &dr, &dg, &db);
+          } 
+          else {
+            dr = dg = db = 0;
+          }
+          col++;
+          red = (unsigned char)(3. * dr);
+          green = (unsigned char)(3. * dg);
+          blue = (unsigned char)(3. * db);
+          b = red;
+          b = (b<<2) + green;
+          b = (b<<2) + blue;
+          if(col < width) {
+            gl2psGetRGB(im, col, row, &dr, &dg, &db);
+          } 
+          else {
+            dr = dg = db = 0;
+          }
+          col++;
+          red = (unsigned char)(3. * dr);
+          green = (unsigned char)(3. * dg);
+          blue = (unsigned char)(3. * db);
+          b = (b<<2) + red;
+          gl2psWriteByte(b);
+          b = 0;
+          icase++;
+        } 
+        else if(icase == 2) {
+          b = green;
+          b = (b<<2) + blue;
+          if(col < width) {
+            gl2psGetRGB(im, col, row, &dr, &dg, &db);
+          }
+          else {
+            dr = dg = db = 0;
+          }
+          col++;
+          red = (unsigned char)(3. * dr);
+          green = (unsigned char)(3. * dg);
+          blue = (unsigned char)(3. * db);
+          b = (b<<2) + red;
+          b = (b<<2) + green;
+          gl2psWriteByte(b);
+          b = 0;
+          icase++;
+        } 
+        else if(icase == 3) {
+          b = blue;
+          if(col < width) {
+            gl2psGetRGB(im, col, row, &dr, &dg, &db);
+          }
+          else {
+            dr = dg = db = 0;
+          }
+          col++;
+          red = (unsigned char)(3. * dr);
+          green = (unsigned char)(3. * dg);
+          blue = (unsigned char)(3. * db);
+          b = (b<<2) + red;
+          b = (b<<2) + green;
+          b = (b<<2) + blue;
+          gl2psWriteByte(b);
+          b = 0;
+          icase = 1;
+        }
+      }
+      gl2psPrintf("\n");
+    }
+  }
+  else if(nbit == 4){ /* color, 4 bits for r and g and b; rgbs following each other */
+    nrgb = width  * 3;
+    nbits = nrgb * nbit;
+    nbyte = nbits / 8;
+    if((nbyte * 8) != nbits) nbyte++; 
+    gl2psPrintf("/rgbstr %d string def\n", nbyte);
+    gl2psPrintf("%d %d %d\n", width, height, nbit);
+    gl2psPrintf("[ %d 0 0 -%d 0 %d ]\n", width, height, height);
+    gl2psPrintf("{ currentfile rgbstr readhexstring pop }\n");
+    gl2psPrintf("false 3\n");
+    gl2psPrintf("colorimage\n");
+    for(row = 0; row < height; row++){
+      col = 0;
+      icase = 1;
+      for(ibyte = 0; ibyte < nbyte; ibyte++){
+        if(icase == 1) {
+          if(col < width) {
+            gl2psGetRGB(im, col, row, &dr, &dg, &db);
+          } 
+          else {
+            dr = dg = db = 0;
+          }
+          col++;
+          red = (unsigned char)(15. * dr);
+          green = (unsigned char)(15. * dg);
+          gl2psPrintf("%x%x", red, green);
+          icase++;
+        } 
+        else if(icase == 2) {
+          blue = (unsigned char)(15. * db);
+          if(col < width) {
+            gl2psGetRGB(im, col, row, &dr, &dg, &db);
+          } 
+          else {
+            dr = dg = db = 0;
+          }
+          col++;
+          red = (unsigned char)(15. * dr);
+          gl2psPrintf("%x%x", blue, red);
+          icase++;
+        }
+        else if(icase == 3) {
+          green = (unsigned char)(15. * dg);
+          blue = (unsigned char)(15. * db);
+          gl2psPrintf("%x%x", green, blue);
+          icase = 1;
+        }
+      }
+      gl2psPrintf("\n");
+    }
+  }
+  else{ /* 8 bit for r and g and b */
+    nbyte = width * 3;
+    gl2psPrintf("/rgbstr %d string def\n", nbyte);
+    gl2psPrintf("%d %d %d\n", width, height, 8);
+    gl2psPrintf("[ %d 0 0 -%d 0 %d ]\n", width, height, height); 
+    gl2psPrintf("{ currentfile rgbstr readhexstring pop }\n");
+    gl2psPrintf("false 3\n");
+    gl2psPrintf("colorimage\n");
+    for(row = 0; row < height; row++){
+      for(col = 0; col < width; col++){
+        gl2psGetRGB(im, col, row, &dr, &dg, &db);
+        red = (unsigned char)(255. * dr);
+        gl2psWriteByte(red);
+        green = (unsigned char)(255. * dg);
+        gl2psWriteByte(green);
+        blue = (unsigned char)(255. * db);
+        gl2psWriteByte(blue);
+      }
+      gl2psPrintf("\n");
+    }
+  }
+  
+  gl2psPrintf("grestore\n");
+}
+
+static void gl2psPrintPostScriptImagemap(GLfloat x, GLfloat y,
+                                         GLsizei width, GLsizei height,
+                                         const unsigned char *imagemap){
+  int i, size;
+  
+  if((width <= 0) || (height <= 0)) return;
+  
+  size = height + height * (width - 1) / 8;
+  
+  gl2psPrintf("gsave\n");
+  gl2psPrintf("%.2f %.2f translate\n", x, y);
+  gl2psPrintf("%d %d scale\n%d %d\ntrue\n", width, height,width, height); 
+  gl2psPrintf("[ %d 0 0 -%d 0 %d ] {<", width, height);
+  for(i = 0; i < size; i++){
+    gl2psWriteByte(*imagemap);
+    imagemap++;
+  }
+  gl2psPrintf(">} imagemask\ngrestore\n");
+}
+
+static void gl2psPrintPostScriptHeader(void)
+{
+  time_t now;
+
+  /* Since compression is not part of the PostScript standard,
+     compressed PostScript files are just gzipped PostScript files
+     ("ps.gz" or "eps.gz") */
+  gl2psPrintGzipHeader();
+
+  time(&now);
+
+  if(gl2ps->format == GL2PS_PS){
+    gl2psPrintf("%%!PS-Adobe-3.0\n");
+  }
+  else{
+    gl2psPrintf("%%!PS-Adobe-3.0 EPSF-3.0\n");
+  }
+
+  gl2psPrintf("%%%%Title: %s\n"
+              "%%%%Creator: GL2PS %d.%d.%d%s, %s\n"
+              "%%%%For: %s\n"
+              "%%%%CreationDate: %s"
+              "%%%%LanguageLevel: 3\n"
+              "%%%%DocumentData: Clean7Bit\n"
+              "%%%%Pages: 1\n",
+              gl2ps->title, GL2PS_MAJOR_VERSION, GL2PS_MINOR_VERSION, 
+              GL2PS_PATCH_VERSION, GL2PS_EXTRA_VERSION, GL2PS_COPYRIGHT,
+              gl2ps->producer, ctime(&now));
+
+  if(gl2ps->format == GL2PS_PS){
+    gl2psPrintf("%%%%Orientation: %s\n"
+                "%%%%DocumentMedia: Default %d %d 0 () ()\n",
+                (gl2ps->options & GL2PS_LANDSCAPE) ? "Landscape" : "Portrait",
+                (gl2ps->options & GL2PS_LANDSCAPE) ? (int)gl2ps->viewport[3] :
+                (int)gl2ps->viewport[2], 
+                (gl2ps->options & GL2PS_LANDSCAPE) ? (int)gl2ps->viewport[2] : 
+                (int)gl2ps->viewport[3]);
+  }
+
+  gl2psPrintf("%%%%BoundingBox: %d %d %d %d\n"
+              "%%%%EndComments\n",
+              (gl2ps->options & GL2PS_LANDSCAPE) ? (int)gl2ps->viewport[1] : 
+              (int)gl2ps->viewport[0],
+              (gl2ps->options & GL2PS_LANDSCAPE) ? (int)gl2ps->viewport[0] :
+              (int)gl2ps->viewport[1],
+              (gl2ps->options & GL2PS_LANDSCAPE) ? (int)gl2ps->viewport[3] : 
+              (int)gl2ps->viewport[2],
+              (gl2ps->options & GL2PS_LANDSCAPE) ? (int)gl2ps->viewport[2] :
+              (int)gl2ps->viewport[3]);
+
+  /* RGB color: r g b C (replace C by G in output to change from rgb to gray)
+     Grayscale: r g b G
+     Font choose: size fontname FC
+     Text string: (string) x y size fontname S??
+     Rotated text string: (string) angle x y size fontname S??R
+     Point primitive: x y size P
+     Line width: width W
+     Line start: x y LS
+     Line joining last point: x y L
+     Line end: x y LE
+     Flat-shaded triangle: x3 y3 x2 y2 x1 y1 T
+     Smooth-shaded triangle: x3 y3 r3 g3 b3 x2 y2 r2 g2 b2 x1 y1 r1 g1 b1 ST */
+
+  gl2psPrintf("%%%%BeginProlog\n"
+              "/gl2psdict 64 dict def gl2psdict begin\n"
+              "0 setlinecap 0 setlinejoin\n"
+              "/tryPS3shading %s def %% set to false to force subdivision\n"
+              "/rThreshold %g def %% red component subdivision threshold\n"
+              "/gThreshold %g def %% green component subdivision threshold\n"
+              "/bThreshold %g def %% blue component subdivision threshold\n",
+              (gl2ps->options & GL2PS_NO_PS3_SHADING) ? "false" : "true",
+              gl2ps->threshold[0], gl2ps->threshold[1], gl2ps->threshold[2]);
+
+  gl2psPrintf("/BD { bind def } bind def\n"
+              "/C  { setrgbcolor } BD\n"
+              "/G  { 0.082 mul exch 0.6094 mul add exch 0.3086 mul add neg 1.0 add setgray } BD\n"
+              "/W  { setlinewidth } BD\n");
+
+  gl2psPrintf("/FC { findfont exch /SH exch def SH scalefont setfont } BD\n"
+              "/SW { dup stringwidth pop } BD\n"
+              "/S  { FC moveto show } BD\n"
+              "/SBC{ FC moveto SW -2 div 0 rmoveto show } BD\n"
+              "/SBR{ FC moveto SW neg 0 rmoveto show } BD\n"
+              "/SCL{ FC moveto 0 SH -2 div rmoveto show } BD\n"
+              "/SCC{ FC moveto SW -2 div SH -2 div rmoveto show } BD\n"
+              "/SCR{ FC moveto SW neg SH -2 div rmoveto show } BD\n"
+              "/STL{ FC moveto 0 SH neg rmoveto show } BD\n"
+              "/STC{ FC moveto SW -2 div SH neg rmoveto show } BD\n"
+              "/STR{ FC moveto SW neg SH neg rmoveto show } BD\n");
+
+  /* rotated text routines: same nameanem with R appended */
+
+  gl2psPrintf("/FCT { FC translate 0 0 } BD\n"
+              "/SR  { gsave FCT moveto rotate show grestore } BD\n"  
+              "/SBCR{ gsave FCT moveto rotate SW -2 div 0 rmoveto show grestore } BD\n"
+              "/SBRR{ gsave FCT moveto rotate SW neg 0 rmoveto show grestore } BD\n"
+              "/SCLR{ gsave FCT moveto rotate 0 SH -2 div rmoveto show grestore} BD\n");
+  gl2psPrintf("/SCCR{ gsave FCT moveto rotate SW -2 div SH -2 div rmoveto show grestore} BD\n"
+              "/SCRR{ gsave FCT moveto rotate SW neg SH -2 div rmoveto show grestore} BD\n"
+              "/STLR{ gsave FCT moveto rotate 0 SH neg rmoveto show grestore } BD\n"
+              "/STCR{ gsave FCT moveto rotate SW -2 div SH neg rmoveto show grestore } BD\n"
+              "/STRR{ gsave FCT moveto rotate SW neg SH neg rmoveto show grestore } BD\n");
+
+  gl2psPrintf("/P  { newpath 0.0 360.0 arc closepath fill } BD\n"
+              "/LS { newpath moveto } BD\n"
+              "/L  { lineto } BD\n"
+              "/LE { lineto stroke } BD\n"
+              "/T  { newpath moveto lineto lineto closepath fill } BD\n");
+  
+  /* Smooth-shaded triangle with PostScript level 3 shfill operator:
+        x3 y3 r3 g3 b3 x2 y2 r2 g2 b2 x1 y1 r1 g1 b1 STshfill */
+
+  gl2psPrintf("/STshfill {\n"
+              "      /b1 exch def /g1 exch def /r1 exch def /y1 exch def /x1 exch def\n"
+              "      /b2 exch def /g2 exch def /r2 exch def /y2 exch def /x2 exch def\n"
+              "      /b3 exch def /g3 exch def /r3 exch def /y3 exch def /x3 exch def\n"
+              "      gsave << /ShadingType 4 /ColorSpace [/DeviceRGB]\n"
+              "      /DataSource [ 0 x1 y1 r1 g1 b1 0 x2 y2 r2 g2 b2 0 x3 y3 r3 g3 b3 ] >>\n"
+              "      shfill grestore } BD\n");
+
+  /* Flat-shaded triangle with middle color:
+        x3 y3 r3 g3 b3 x2 y2 r2 g2 b2 x1 y1 r1 g1 b1 Tm */
+
+  gl2psPrintf(/* stack : x3 y3 r3 g3 b3 x2 y2 r2 g2 b2 x1 y1 r1 g1 b1 */
+              "/Tm { 3 -1 roll 8 -1 roll 13 -1 roll add add 3 div\n" /* r = (r1+r2+r3)/3 */
+              /* stack : x3 y3 g3 b3 x2 y2 g2 b2 x1 y1 g1 b1 r */
+              "      3 -1 roll 7 -1 roll 11 -1 roll add add 3 div\n" /* g = (g1+g2+g3)/3 */
+              /* stack : x3 y3 b3 x2 y2 b2 x1 y1 b1 r g b */
+              "      3 -1 roll 6 -1 roll 9 -1 roll add add 3 div" /* b = (b1+b2+b3)/3 */
+              /* stack : x3 y3 x2 y2 x1 y1 r g b */
+              " C T } BD\n");
+
+  /* Split triangle in four sub-triangles (at sides middle points) and call the
+     STnoshfill procedure on each, interpolating the colors in RGB space:
+        x3 y3 r3 g3 b3 x2 y2 r2 g2 b2 x1 y1 r1 g1 b1 STsplit
+     (in procedure comments key: (Vi) = xi yi ri gi bi) */
+
+  gl2psPrintf("/STsplit {\n"
+              "      4 index 15 index add 0.5 mul\n" /* x13 = (x1+x3)/2 */
+              "      4 index 15 index add 0.5 mul\n" /* y13 = (y1+y3)/2 */
+              "      4 index 15 index add 0.5 mul\n" /* r13 = (r1+r3)/2 */
+              "      4 index 15 index add 0.5 mul\n" /* g13 = (g1+g3)/2 */
+              "      4 index 15 index add 0.5 mul\n" /* b13 = (b1+b3)/2 */
+              "      5 copy 5 copy 25 15 roll\n");
+
+  /* at his point, stack = (V3) (V13) (V13) (V13) (V2) (V1) */
+
+  gl2psPrintf("      9 index 30 index add 0.5 mul\n" /* x23 = (x2+x3)/2 */
+              "      9 index 30 index add 0.5 mul\n" /* y23 = (y2+y3)/2 */
+              "      9 index 30 index add 0.5 mul\n" /* r23 = (r2+r3)/2 */
+              "      9 index 30 index add 0.5 mul\n" /* g23 = (g2+g3)/2 */
+              "      9 index 30 index add 0.5 mul\n" /* b23 = (b2+b3)/2 */
+              "      5 copy 5 copy 35 5 roll 25 5 roll 15 5 roll\n");
+
+  /* stack = (V3) (V13) (V23) (V13) (V23) (V13) (V23) (V2) (V1) */
+
+  gl2psPrintf("      4 index 10 index add 0.5 mul\n" /* x12 = (x1+x2)/2 */
+              "      4 index 10 index add 0.5 mul\n" /* y12 = (y1+y2)/2 */
+              "      4 index 10 index add 0.5 mul\n" /* r12 = (r1+r2)/2 */
+              "      4 index 10 index add 0.5 mul\n" /* g12 = (g1+g2)/2 */
+              "      4 index 10 index add 0.5 mul\n" /* b12 = (b1+b2)/2 */
+              "      5 copy 5 copy 40 5 roll 25 5 roll 15 5 roll 25 5 roll\n");
+  
+  /* stack = (V3) (V13) (V23) (V13) (V12) (V23) (V13) (V1) (V12) (V23) (V12) (V2) */
+
+  gl2psPrintf("      STnoshfill STnoshfill STnoshfill STnoshfill } BD\n");
+  
+  /* Gouraud shaded triangle using recursive subdivision until the difference
+     between corner colors does not exceed the thresholds:
+        x3 y3 r3 g3 b3 x2 y2 r2 g2 b2 x1 y1 r1 g1 b1 STnoshfill  */
+
+  gl2psPrintf("/STnoshfill {\n"
+              "      2 index 8 index sub abs rThreshold gt\n" /* |r1-r2|>rth */
+              "      { STsplit }\n"
+              "      { 1 index 7 index sub abs gThreshold gt\n" /* |g1-g2|>gth */
+              "        { STsplit }\n"
+              "        { dup 6 index sub abs bThreshold gt\n" /* |b1-b2|>bth */
+              "          { STsplit }\n"
+              "          { 2 index 13 index sub abs rThreshold gt\n" /* |r1-r3|>rht */
+              "            { STsplit }\n"
+              "            { 1 index 12 index sub abs gThreshold gt\n" /* |g1-g3|>gth */
+              "              { STsplit }\n"
+              "              { dup 11 index sub abs bThreshold gt\n" /* |b1-b3|>bth */
+              "                { STsplit }\n"
+              "                { 7 index 13 index sub abs rThreshold gt\n"); /* |r2-r3|>rht */
+  gl2psPrintf("                  { STsplit }\n"
+              "                  { 6 index 12 index sub abs gThreshold gt\n" /* |g2-g3|>gth */
+              "                    { STsplit }\n"
+              "                    { 5 index 11 index sub abs bThreshold gt\n" /* |b2-b3|>bth */
+              "                      { STsplit }\n"
+              "                      { Tm }\n" /* all colors sufficiently similar */
+              "                      ifelse }\n"
+              "                    ifelse }\n"
+              "                  ifelse }\n"
+              "                ifelse }\n"
+              "              ifelse }\n"
+              "            ifelse }\n"
+              "          ifelse }\n"
+              "        ifelse }\n"
+              "      ifelse } BD\n");
+  
+  gl2psPrintf("tryPS3shading\n"
+              "{ /shfill where\n"
+              "  { /ST { STshfill } BD }\n"
+              "  { /ST { STnoshfill } BD }\n"
+              "  ifelse }\n"
+              "{ /ST { STnoshfill } BD }\n"
+              "ifelse\n");
+
+  gl2psPrintf("end\n"
+              "%%%%EndProlog\n"
+              "%%%%BeginSetup\n"
+              "/DeviceRGB setcolorspace\n"
+              "gl2psdict begin\n"
+              "%%%%EndSetup\n"
+              "%%%%Page: 1 1\n"
+              "%%%%BeginPageSetup\n");
+  
+  if(gl2ps->options & GL2PS_LANDSCAPE){
+    gl2psPrintf("%d 0 translate 90 rotate\n",
+                (int)gl2ps->viewport[3]);
+  }
+
+  gl2psPrintf("%%%%EndPageSetup\n"
+              "mark\n"
+              "gsave\n"
+              "1.0 1.0 scale\n");
+          
+  if(gl2ps->options & GL2PS_DRAW_BACKGROUND){
+    gl2psPrintf("%g %g %g C\n"
+                "newpath %d %d moveto %d %d lineto %d %d lineto %d %d lineto\n"
+                "closepath fill\n",
+                gl2ps->bgcolor[0], gl2ps->bgcolor[1], gl2ps->bgcolor[2], 
+                (int)gl2ps->viewport[0], (int)gl2ps->viewport[1], (int)gl2ps->viewport[2], 
+                (int)gl2ps->viewport[1], (int)gl2ps->viewport[2], (int)gl2ps->viewport[3], 
+                (int)gl2ps->viewport[0], (int)gl2ps->viewport[3]);
+  }
+}
+
+static void gl2psPrintPostScriptColor(GL2PSrgba rgba)
+{
+  if(!gl2psSameColor(gl2ps->lastrgba, rgba)){
+    gl2psSetLastColor(rgba);
+    gl2psPrintf("%g %g %g C\n", rgba[0], rgba[1], rgba[2]);
+  }
+}
+
+static void gl2psResetPostScriptColor(void)
+{
+  gl2ps->lastrgba[0] = gl2ps->lastrgba[1] = gl2ps->lastrgba[2] = -1.;
+}
+
+static void gl2psEndPostScriptLine(void)
+{
+  int i;
+  if(gl2ps->lastvertex.rgba[0] >= 0.){
+    gl2psPrintf("%g %g LE\n", gl2ps->lastvertex.xyz[0], gl2ps->lastvertex.xyz[1]);
+    for(i = 0; i < 3; i++)
+      gl2ps->lastvertex.xyz[i] = -1.;
+    for(i = 0; i < 4; i++)
+      gl2ps->lastvertex.rgba[i] = -1.;
+  }
+}
+
+static void gl2psParseStipplePattern(GLushort pattern, GLint factor, 
+                                     int *nb, int array[10])
+{
+  int i, n;
+  int on[8] = {0, 0, 0, 0, 0, 0, 0, 0};
+  int off[8] = {0, 0, 0, 0, 0, 0, 0, 0};
+  char tmp[16];
+
+  /* extract the 16 bits from the OpenGL stipple pattern */
+  for(n = 15; n >= 0; n--){
+    tmp[n] = (char)(pattern & 0x01);
+    pattern >>= 1;
+  }
+  /* compute the on/off pixel sequence */
+  n = 0;
+  for(i = 0; i < 8; i++){
+    while(n < 16 && !tmp[n]){ off[i]++; n++; }
+    while(n < 16 && tmp[n]){ on[i]++; n++; }
+    if(n >= 15){ i++; break; }
+  }
+
+  /* store the on/off array from right to left, starting with off
+     pixels. The PostScript specification allows for at most 11
+     elements in the on/off array, so we limit ourselves to 5 on/off
+     couples (our longest possible array is thus [on4 off4 on3 off3
+     on2 off2 on1 off1 on0 off0]) */
+  *nb = 0;
+  for(n = i - 1; n >= 0; n--){
+    array[(*nb)++] = factor * on[n];
+    array[(*nb)++] = factor * off[n];
+    if(*nb == 10) break;
+  }
+}
+
+static int gl2psPrintPostScriptDash(GLushort pattern, GLint factor, const char *str)
+{
+  int len = 0, i, n, array[10];
+
+  if(pattern == gl2ps->lastpattern && factor == gl2ps->lastfactor)
+    return 0;
+  
+  gl2ps->lastpattern = pattern;
+  gl2ps->lastfactor = factor;
+  
+  if(!pattern || !factor){
+    /* solid line */
+    len += gl2psPrintf("[] 0 %s\n", str);
+  }
+  else{
+    gl2psParseStipplePattern(pattern, factor, &n, array);
+    len += gl2psPrintf("[");
+    for(i = 0; i < n; i++){
+      if(i) len += gl2psPrintf(" ");
+      len += gl2psPrintf("%d", array[i]);
+    }
+    len += gl2psPrintf("] 0 %s\n", str);
+  }
+  
+  return len;
+}
+
+static void gl2psPrintPostScriptPrimitive(void *data)
+{
+  int newline;
+  GL2PSprimitive *prim;
+
+  prim = *(GL2PSprimitive**)data;
+
+  if((gl2ps->options & GL2PS_OCCLUSION_CULL) && prim->culled) return;
+
+  /* Every effort is made to draw lines as connected segments (i.e.,
+     using a single PostScript path): this is the only way to get nice
+     line joins and to not restart the stippling for every line
+     segment. So if the primitive to print is not a line we must first
+     finish the current line (if any): */
+  if(prim->type != GL2PS_LINE) gl2psEndPostScriptLine();
+
+  switch(prim->type){
+  case GL2PS_POINT :
+    gl2psPrintPostScriptColor(prim->verts[0].rgba);
+    gl2psPrintf("%g %g %g P\n", 
+                prim->verts[0].xyz[0], prim->verts[0].xyz[1], 0.5 * prim->width);
+    break;
+  case GL2PS_LINE :
+    if(!gl2psSamePosition(gl2ps->lastvertex.xyz, prim->verts[0].xyz) ||
+       !gl2psSameColor(gl2ps->lastrgba, prim->verts[0].rgba) ||
+       gl2ps->lastlinewidth != prim->width ||
+       gl2ps->lastpattern != prim->pattern ||
+       gl2ps->lastfactor != prim->factor){
+      /* End the current line if the new segment does not start where
+         the last one ended, or if the color, the width or the
+         stippling have changed (multi-stroking lines with changing
+         colors is necessary until we use /shfill for lines;
+         unfortunately this means that at the moment we can screw up
+         line stippling for smooth-shaded lines) */
+      gl2psEndPostScriptLine();
+      newline = 1;
+    }
+    else{
+      newline = 0;
+    }
+    if(gl2ps->lastlinewidth != prim->width){
+      gl2ps->lastlinewidth = prim->width;
+      gl2psPrintf("%g W\n", gl2ps->lastlinewidth);
+    }
+    gl2psPrintPostScriptDash(prim->pattern, prim->factor, "setdash");
+    gl2psPrintPostScriptColor(prim->verts[0].rgba);
+    gl2psPrintf("%g %g %s\n", prim->verts[0].xyz[0], prim->verts[0].xyz[1],
+                newline ? "LS" : "L");
+    gl2ps->lastvertex = prim->verts[1];
+    break;
+  case GL2PS_TRIANGLE :
+    if(!gl2psVertsSameColor(prim)){
+      gl2psResetPostScriptColor();
+      gl2psPrintf("%g %g %g %g %g %g %g %g %g %g %g %g %g %g %g ST\n",
+                  prim->verts[2].xyz[0], prim->verts[2].xyz[1],
+                  prim->verts[2].rgba[0], prim->verts[2].rgba[1],
+                  prim->verts[2].rgba[2], prim->verts[1].xyz[0],
+                  prim->verts[1].xyz[1], prim->verts[1].rgba[0],
+                  prim->verts[1].rgba[1], prim->verts[1].rgba[2],
+                  prim->verts[0].xyz[0], prim->verts[0].xyz[1],
+                  prim->verts[0].rgba[0], prim->verts[0].rgba[1],
+                  prim->verts[0].rgba[2]);
+    }
+    else{
+      gl2psPrintPostScriptColor(prim->verts[0].rgba);
+      gl2psPrintf("%g %g %g %g %g %g T\n",
+                  prim->verts[2].xyz[0], prim->verts[2].xyz[1],
+                  prim->verts[1].xyz[0], prim->verts[1].xyz[1],
+                  prim->verts[0].xyz[0], prim->verts[0].xyz[1]);
+    }
+    break;
+  case GL2PS_QUADRANGLE :
+    gl2psMsg(GL2PS_WARNING, "There should not be any quad left to print");
+    break;
+  case GL2PS_PIXMAP :
+    gl2psPrintPostScriptPixmap(prim->verts[0].xyz[0], prim->verts[0].xyz[1],
+                               prim->data.image);
+    break;
+  case GL2PS_IMAGEMAP :
+    if(prim->data.image->type != GL2PS_IMAGEMAP_WRITTEN){
+      gl2psPrintPostScriptColor(prim->verts[0].rgba);
+      gl2psPrintPostScriptImagemap(prim->data.image->pixels[0],
+                                   prim->data.image->pixels[1],
+                                   prim->data.image->width, prim->data.image->height,
+                                   (const unsigned char*)(&(prim->data.image->pixels[2])));
+      prim->data.image->type = GL2PS_IMAGEMAP_WRITTEN;
+    }
+    break;
+  case GL2PS_TEXT :
+    gl2psPrintPostScriptColor(prim->verts[0].rgba);
+    gl2psPrintf("(%s) ", prim->data.text->str);
+    if(prim->data.text->angle)
+      gl2psPrintf("%g ", prim->data.text->angle);
+    gl2psPrintf("%g %g %d /%s ",
+                prim->verts[0].xyz[0], prim->verts[0].xyz[1],
+                prim->data.text->fontsize, prim->data.text->fontname);
+    switch(prim->data.text->alignment){
+    case GL2PS_TEXT_C:
+      gl2psPrintf(prim->data.text->angle ? "SCCR\n" : "SCC\n");
+      break;
+    case GL2PS_TEXT_CL:
+      gl2psPrintf(prim->data.text->angle ? "SCLR\n" : "SCL\n");
+      break;
+    case GL2PS_TEXT_CR:
+      gl2psPrintf(prim->data.text->angle ? "SCRR\n" : "SCR\n");
+      break;
+    case GL2PS_TEXT_B:
+      gl2psPrintf(prim->data.text->angle ? "SBCR\n" : "SBC\n");
+      break;
+    case GL2PS_TEXT_BR:
+      gl2psPrintf(prim->data.text->angle ? "SBRR\n" : "SBR\n");
+      break;
+    case GL2PS_TEXT_T:
+      gl2psPrintf(prim->data.text->angle ? "STCR\n" : "STC\n");
+      break;
+    case GL2PS_TEXT_TL:
+      gl2psPrintf(prim->data.text->angle ? "STLR\n" : "STL\n");
+      break;
+    case GL2PS_TEXT_TR:
+      gl2psPrintf(prim->data.text->angle ? "STRR\n" : "STR\n");
+      break;
+    case GL2PS_TEXT_BL:
+    default:
+      gl2psPrintf(prim->data.text->angle ? "SR\n" : "S\n");
+      break;
+    }
+    break;
+  case GL2PS_SPECIAL :
+    /* alignment contains the format for which the special output text
+       is intended */
+    if(prim->data.text->alignment == GL2PS_PS ||
+       prim->data.text->alignment == GL2PS_EPS)
+      gl2psPrintf("%s\n", prim->data.text->str);
+    break;
+  default :
+    break;
+  }
+}
+
+static void gl2psPrintPostScriptFooter(void)
+{
+  gl2psPrintf("grestore\n"
+              "showpage\n"
+              "cleartomark\n"
+              "%%%%PageTrailer\n"
+              "%%%%Trailer\n"
+              "end\n"
+              "%%%%EOF\n");
+
+  gl2psPrintGzipFooter();
+}
+
+static void gl2psPrintPostScriptBeginViewport(GLint viewport[4])
+{
+  GLint index;
+  GLfloat rgba[4];
+  int x = viewport[0], y = viewport[1], w = viewport[2], h = viewport[3];
+
+  glRenderMode(GL_FEEDBACK);
+
+  if(gl2ps->header){
+    gl2psPrintPostScriptHeader();
+    gl2ps->header = GL_FALSE;
+  }
+
+  gl2psPrintf("gsave\n"
+              "1.0 1.0 scale\n");
+
+  if(gl2ps->options & GL2PS_DRAW_BACKGROUND){
+    if(gl2ps->colormode == GL_RGBA || gl2ps->colorsize == 0){
+      glGetFloatv(GL_COLOR_CLEAR_VALUE, rgba);
+    }
+    else{
+      glGetIntegerv(GL_INDEX_CLEAR_VALUE, &index);
+      rgba[0] = gl2ps->colormap[index][0];
+      rgba[1] = gl2ps->colormap[index][1];
+      rgba[2] = gl2ps->colormap[index][2];
+      rgba[3] = 1.0F;
+    }
+    gl2psPrintf("%g %g %g C\n"
+                "newpath %d %d moveto %d %d lineto %d %d lineto %d %d lineto\n"
+                "closepath fill\n",
+                rgba[0], rgba[1], rgba[2], 
+                x, y, x+w, y, x+w, y+h, x, y+h);
+  }
+    
+  gl2psPrintf("newpath %d %d moveto %d %d lineto %d %d lineto %d %d lineto\n"
+              "closepath clip\n",
+              x, y, x+w, y, x+w, y+h, x, y+h);
+  
+}
+
+static GLint gl2psPrintPostScriptEndViewport(void)
+{
+  GLint res;
+
+  res = gl2psPrintPrimitives();
+  gl2psPrintf("grestore\n");
+  return res;
+}
+
+static void gl2psPrintPostScriptFinalPrimitive(void)
+{
+  /* End any remaining line, if any */
+  gl2psEndPostScriptLine();
+}
+
+/* definition of the PostScript and Encapsulated PostScript backends */
+
+static GL2PSbackend gl2psPS = {
+  gl2psPrintPostScriptHeader,
+  gl2psPrintPostScriptFooter,
+  gl2psPrintPostScriptBeginViewport,
+  gl2psPrintPostScriptEndViewport,
+  gl2psPrintPostScriptPrimitive,
+  gl2psPrintPostScriptFinalPrimitive,
+  "ps",
+  "Postscript"
+};
+
+static GL2PSbackend gl2psEPS = {
+  gl2psPrintPostScriptHeader,
+  gl2psPrintPostScriptFooter,
+  gl2psPrintPostScriptBeginViewport,
+  gl2psPrintPostScriptEndViewport,
+  gl2psPrintPostScriptPrimitive,
+  gl2psPrintPostScriptFinalPrimitive,
+  "eps",
+  "Encapsulated Postscript"
+};
+
+/********************************************************************* 
+ *
+ * LaTeX routines
+ *
+ *********************************************************************/
+
+static void gl2psPrintTeXHeader(void)
+{
+  char name[256];
+  time_t now;
+  int i;
+
+  if(gl2ps->filename && strlen(gl2ps->filename) < 256){
+    for(i = strlen(gl2ps->filename)-1; i >= 0; i--){
+      if(gl2ps->filename[i] == '.'){
+        strncpy(name, gl2ps->filename, i);
+        name[i] = '\0';
+        break;
+      }
+    }
+    if(i <= 0) strcpy(name, gl2ps->filename);
+  }
+  else{
+    strcpy(name, "untitled");
+  }
+
+  time(&now);
+
+  fprintf(gl2ps->stream, 
+          "%% Title: %s\n"
+          "%% Creator: GL2PS %d.%d.%d%s, %s\n"
+          "%% For: %s\n"
+          "%% CreationDate: %s",
+          gl2ps->title, GL2PS_MAJOR_VERSION, GL2PS_MINOR_VERSION,
+          GL2PS_PATCH_VERSION, GL2PS_EXTRA_VERSION, GL2PS_COPYRIGHT,
+          gl2ps->producer, ctime(&now));
+
+  fprintf(gl2ps->stream, 
+          "\\setlength{\\unitlength}{1pt}\n"
+          "\\begin{picture}(0,0)\n"
+          "\\includegraphics{%s}\n"
+          "\\end{picture}%%\n"
+          "%s\\begin{picture}(%d,%d)(0,0)\n",
+          name, (gl2ps->options & GL2PS_LANDSCAPE) ? "\\rotatebox{90}{" : "",
+          (int)gl2ps->viewport[2], (int)gl2ps->viewport[3]);
+}
+
+static void gl2psPrintTeXPrimitive(void *data)
+{
+  GL2PSprimitive *prim;
+
+  prim = *(GL2PSprimitive**)data;
+
+  switch(prim->type){
+  case GL2PS_TEXT :
+    fprintf(gl2ps->stream, "\\fontsize{%d}{0}\n\\selectfont", 
+            prim->data.text->fontsize);
+    fprintf(gl2ps->stream, "\\put(%g,%g){\\makebox(0,0)",
+            prim->verts[0].xyz[0], prim->verts[0].xyz[1]);
+    switch(prim->data.text->alignment){
+    case GL2PS_TEXT_C:
+      fprintf(gl2ps->stream, "{");
+      break;
+    case GL2PS_TEXT_CL:
+      fprintf(gl2ps->stream, "[l]{");
+      break;
+    case GL2PS_TEXT_CR:
+      fprintf(gl2ps->stream, "[r]{");
+      break;
+    case GL2PS_TEXT_B:
+      fprintf(gl2ps->stream, "[b]{");
+      break;
+    case GL2PS_TEXT_BR:
+      fprintf(gl2ps->stream, "[br]{");
+      break;
+    case GL2PS_TEXT_T:
+      fprintf(gl2ps->stream, "[t]{");
+      break;
+    case GL2PS_TEXT_TL:
+      fprintf(gl2ps->stream, "[tl]{");
+      break;
+    case GL2PS_TEXT_TR:
+      fprintf(gl2ps->stream, "[tr]{");
+      break;
+    case GL2PS_TEXT_BL:
+    default:
+      fprintf(gl2ps->stream, "[bl]{");
+      break;
+    }
+    if(prim->data.text->angle)
+      fprintf(gl2ps->stream, "\\rotatebox{%g}{", prim->data.text->angle);
+    fprintf(gl2ps->stream, "\\textcolor[rgb]{%g,%g,%g}{{%s}}",
+            prim->verts[0].rgba[0], prim->verts[0].rgba[1], prim->verts[0].rgba[2],
+            prim->data.text->str);
+    if(prim->data.text->angle)
+      fprintf(gl2ps->stream, "}");
+    fprintf(gl2ps->stream, "}}\n");
+    break;
+  case GL2PS_SPECIAL :
+    /* alignment contains the format for which the special output text
+       is intended */
+    if (prim->data.text->alignment == GL2PS_TEX)
+      fprintf(gl2ps->stream, "%s\n", prim->data.text->str);
+    break;
+  default :
+    break;
+  }
+}
+
+static void gl2psPrintTeXFooter(void)
+{
+  fprintf(gl2ps->stream, "\\end{picture}%s\n",
+          (gl2ps->options & GL2PS_LANDSCAPE) ? "}" : "");
+}
+
+static void gl2psPrintTeXBeginViewport(GLint viewport[4])
+{
+  glRenderMode(GL_FEEDBACK);
+  
+  if(gl2ps->header){
+    gl2psPrintTeXHeader();
+    gl2ps->header = GL_FALSE;
+  }
+}
+
+static GLint gl2psPrintTeXEndViewport(void)
+{
+  return gl2psPrintPrimitives();
+}
+
+static void gl2psPrintTeXFinalPrimitive(void)
+{
+}
+
+/* definition of the LaTeX backend */
+
+static GL2PSbackend gl2psTEX = {
+  gl2psPrintTeXHeader,
+  gl2psPrintTeXFooter,
+  gl2psPrintTeXBeginViewport,
+  gl2psPrintTeXEndViewport,
+  gl2psPrintTeXPrimitive,
+  gl2psPrintTeXFinalPrimitive,
+  "tex",
+  "LaTeX text"
+};
+
+/********************************************************************* 
+ *
+ * PDF routines
+ *
+ *********************************************************************/
+
+static int gl2psPrintPDFCompressorType(void)
+{
+#if defined(GL2PS_HAVE_ZLIB)
+  if(gl2ps->options & GL2PS_COMPRESS){
+    return fprintf(gl2ps->stream, "/Filter [/FlateDecode]\n");
+  }
+#endif
+  return 0;
+}
+
+static int gl2psPrintPDFStrokeColor(GL2PSrgba rgba)
+{
+  int i, offs = 0;
+
+  gl2psSetLastColor(rgba);
+  for(i = 0; i < 3; ++i){
+    if(GL2PS_ZERO(rgba[i]))
+      offs += gl2psPrintf("%.0f ", 0.);
+    else if(rgba[i] < 1e-4 || rgba[i] > 1e6) /* avoid %e formatting */
+      offs += gl2psPrintf("%f ", rgba[i]);
+    else
+      offs += gl2psPrintf("%g ", rgba[i]);
+  }
+  offs += gl2psPrintf("RG\n");
+  return offs;
+}
+
+static int gl2psPrintPDFFillColor(GL2PSrgba rgba)
+{
+  int i, offs = 0;
+  
+  for(i = 0; i < 3; ++i){
+    if(GL2PS_ZERO(rgba[i]))
+      offs += gl2psPrintf("%.0f ", 0.);
+    else if(rgba[i] < 1e-4 || rgba[i] > 1e6) /* avoid %e formatting */
+      offs += gl2psPrintf("%f ", rgba[i]);
+    else
+      offs += gl2psPrintf("%g ", rgba[i]);
+  }
+  offs += gl2psPrintf("rg\n");
+  return offs;
+}
+
+static int gl2psPrintPDFLineWidth(GLfloat lw)
+{
+  if(GL2PS_ZERO(lw))
+    return gl2psPrintf("%.0f w\n", 0.);
+  else if(lw < 1e-4 || lw > 1e6) /* avoid %e formatting */
+    return gl2psPrintf("%f w\n", lw);
+  else
+    return gl2psPrintf("%g w\n", lw);
+}
+
+static void gl2psPutPDFText(GL2PSstring *text, int cnt, GLfloat x, GLfloat y)
+{
+  gl2ps->streamlength += 
+    gl2psPrintf("BT\n"
+                "/F%d %d Tf\n"
+                "%f %f Td\n"
+                "(%s) Tj\n"
+                "ET\n", 
+                cnt, text->fontsize, x, y, text->str);  
+}
+
+static void gl2psPutPDFImage(GL2PSimage *image, int cnt, GLfloat x, GLfloat y)
+{
+  gl2ps->streamlength += 
+    gl2psPrintf("q\n"
+                "%d 0 0 %d %f %f cm\n"
+                "/Im%d Do\n"
+                "Q\n",
+                (int)image->width, (int)image->height, x, y, cnt);
+}
+
+static void gl2psPDFstacksInit(void)
+{
+  gl2ps->objects_stack = 7 /* FIXED_XREF_ENTRIES */ + 1; 
+  gl2ps->extgs_stack = 0;   
+  gl2ps->font_stack = 0;    
+  gl2ps->im_stack = 0;      
+  gl2ps->trgroupobjects_stack = 0;    
+  gl2ps->shader_stack = 0;  
+  gl2ps->mshader_stack = 0; 
+}
+
+static void gl2psPDFgroupObjectInit(GL2PSpdfgroup *gro)
+{
+  if(!gro)
+    return;
+  
+  gro->ptrlist = NULL;
+  gro->fontno = gro->gsno = gro->imno = gro->maskshno = gro->shno 
+    = gro->trgroupno = gro->fontobjno = gro->imobjno = gro->shobjno 
+    = gro->maskshobjno = gro->gsobjno = gro->trgroupobjno = -1;
+}
+
+/* Build up group objects and assign name and object numbers */
+
+static void gl2psPDFgroupListInit(void)
+{
+  int i;
+  GL2PSprimitive *p = NULL;
+  GL2PSpdfgroup gro;
+  int lasttype = GL2PS_NO_TYPE;
+  GL2PSrgba lastrgba = {-1.0F, -1.0F, -1.0F, -1.0F};
+  GLushort lastpattern = 0;
+  GLint lastfactor = 0;
+  GLfloat lastwidth = 1;
+  GL2PStriangle lastt, tmpt;
+  int lastTriangleWasNotSimpleWithSameColor = 0;
+
+  if(!gl2ps->pdfprimlist)
+    return;
+
+  gl2ps->pdfgrouplist = gl2psListCreate(500, 500, sizeof(GL2PSpdfgroup));
+  gl2psInitTriangle(&lastt);
+
+  for(i = 0; i < gl2psListNbr(gl2ps->pdfprimlist); ++i){  
+    p = *(GL2PSprimitive**)gl2psListPointer(gl2ps->pdfprimlist, i);
+    switch(p->type){
+    case GL2PS_PIXMAP:
+      gl2psPDFgroupObjectInit(&gro);
+      gro.ptrlist = gl2psListCreate(1, 2, sizeof(GL2PSprimitive*));
+      gro.imno = gl2ps->im_stack++;
+      gl2psListAdd(gro.ptrlist, &p);
+      gl2psListAdd(gl2ps->pdfgrouplist, &gro);
+      break;
+    case GL2PS_TEXT:
+      gl2psPDFgroupObjectInit(&gro);
+      gro.ptrlist = gl2psListCreate(1, 2, sizeof(GL2PSprimitive*));
+      gro.fontno = gl2ps->font_stack++;
+      gl2psListAdd(gro.ptrlist, &p);
+      gl2psListAdd(gl2ps->pdfgrouplist, &gro);
+      break;
+    case GL2PS_LINE:
+      if(lasttype != p->type || lastwidth != p->width || 
+         lastpattern != p->pattern || lastfactor != p->factor ||
+         !gl2psSameColor(p->verts[0].rgba, lastrgba)){
+        gl2psPDFgroupObjectInit(&gro);
+        gro.ptrlist = gl2psListCreate(1, 2, sizeof(GL2PSprimitive*));
+        gl2psListAdd(gro.ptrlist, &p);
+        gl2psListAdd(gl2ps->pdfgrouplist, &gro);
+      }
+      else{
+        gl2psListAdd(gro.ptrlist, &p);
+      }
+      lastpattern = p->pattern;
+      lastfactor = p->factor;
+      lastwidth = p->width;
+      lastrgba[0] = p->verts[0].rgba[0];
+      lastrgba[1] = p->verts[0].rgba[1];
+      lastrgba[2] = p->verts[0].rgba[2];
+      break;
+    case GL2PS_POINT:
+      if(lasttype != p->type || lastwidth != p->width || 
+         !gl2psSameColor(p->verts[0].rgba, lastrgba)){
+        gl2psPDFgroupObjectInit(&gro);
+        gro.ptrlist = gl2psListCreate(1,2,sizeof(GL2PSprimitive*));
+        gl2psListAdd(gro.ptrlist, &p);
+        gl2psListAdd(gl2ps->pdfgrouplist, &gro);
+      }
+      else{
+        gl2psListAdd(gro.ptrlist, &p);
+      }
+      lastwidth = p->width;
+      lastrgba[0] = p->verts[0].rgba[0];
+      lastrgba[1] = p->verts[0].rgba[1];
+      lastrgba[2] = p->verts[0].rgba[2];
+      break;
+    case GL2PS_TRIANGLE:
+      gl2psFillTriangleFromPrimitive(&tmpt, p, GL_TRUE);
+      lastTriangleWasNotSimpleWithSameColor = 
+        !(tmpt.prop & T_CONST_COLOR && tmpt.prop & T_ALPHA_1) ||
+        !gl2psSameColor(tmpt.vertex[0].rgba, lastt.vertex[0].rgba);
+      if(lasttype == p->type && tmpt.prop == lastt.prop && 
+         lastTriangleWasNotSimpleWithSameColor){
+        /* TODO Check here for last alpha */
+        gl2psListAdd(gro.ptrlist, &p);
+      }
+      else{
+        gl2psPDFgroupObjectInit(&gro);
+        gro.ptrlist = gl2psListCreate(1, 2, sizeof(GL2PSprimitive*));
+        gl2psListAdd(gro.ptrlist, &p);
+        gl2psListAdd(gl2ps->pdfgrouplist, &gro);
+      }
+      lastt = tmpt;
+      break;
+    default:
+      break;
+    } 
+    lasttype = p->type;
+  }
+}
+
+static void gl2psSortOutTrianglePDFgroup(GL2PSpdfgroup *gro)
+{
+  GL2PStriangle t;
+  GL2PSprimitive *prim = NULL;
+  
+  if(!gro)
+    return;
+
+  if(!gl2psListNbr(gro->ptrlist))
+    return;
+
+  prim = *(GL2PSprimitive**)gl2psListPointer(gro->ptrlist, 0);
+
+  if(prim->type != GL2PS_TRIANGLE)
+    return;
+
+  gl2psFillTriangleFromPrimitive(&t, prim, GL_TRUE);
+  
+  if(t.prop & T_CONST_COLOR && t.prop & T_ALPHA_LESS_1){        
+    gro->gsno = gl2ps->extgs_stack++; 
+    gro->gsobjno = gl2ps->objects_stack ++;
+  }
+  else if(t.prop & T_CONST_COLOR && t.prop & T_VAR_ALPHA){              
+    gro->gsno = gl2ps->extgs_stack++;
+    gro->gsobjno = gl2ps->objects_stack++;
+    gro->trgroupno = gl2ps->trgroupobjects_stack++; 
+    gro->trgroupobjno = gl2ps->objects_stack++;
+    gro->maskshno = gl2ps->mshader_stack++;
+    gro->maskshobjno = gl2ps->objects_stack++;
+  }
+  else if(t.prop & T_VAR_COLOR && t.prop & T_ALPHA_1){          
+    gro->shno = gl2ps->shader_stack++;
+    gro->shobjno = gl2ps->objects_stack++;
+  }
+  else if(t.prop & T_VAR_COLOR && t.prop & T_ALPHA_LESS_1){             
+    gro->gsno = gl2ps->extgs_stack++;
+    gro->gsobjno = gl2ps->objects_stack++;
+    gro->shno = gl2ps->shader_stack++; 
+    gro->shobjno = gl2ps->objects_stack++;
+  }
+  else if(t.prop & T_VAR_COLOR && t.prop & T_VAR_ALPHA){                
+    gro->gsno = gl2ps->extgs_stack++;
+    gro->gsobjno = gl2ps->objects_stack++;
+    gro->shno = gl2ps->shader_stack++; 
+    gro->shobjno = gl2ps->objects_stack++;
+    gro->trgroupno = gl2ps->trgroupobjects_stack++; 
+    gro->trgroupobjno = gl2ps->objects_stack++;
+    gro->maskshno = gl2ps->mshader_stack++;
+    gro->maskshobjno = gl2ps->objects_stack++;
+  }
+}
+
+/* Main stream data */
+
+static void gl2psPDFgroupListWriteMainStream(void)
+{
+  int i, j, lastel;
+  GL2PSprimitive *prim = NULL, *prev = NULL;
+  GL2PSpdfgroup *gro;
+  GL2PStriangle t;
+
+  if(!gl2ps->pdfgrouplist)
+    return;
+
+  for(i = 0; i < gl2psListNbr(gl2ps->pdfgrouplist); ++i){
+    gro = (GL2PSpdfgroup*)gl2psListPointer(gl2ps->pdfgrouplist, i);
+
+    lastel = gl2psListNbr(gro->ptrlist) - 1;
+    if(lastel < 0)
+      continue;
+
+    prim = *(GL2PSprimitive**)gl2psListPointer(gro->ptrlist, 0);
+
+    switch(prim->type){
+    case GL2PS_POINT:
+      gl2ps->streamlength += gl2psPrintf("1 J\n");
+      gl2ps->streamlength += gl2psPrintPDFLineWidth(prim->width);
+      gl2ps->streamlength += gl2psPrintPDFStrokeColor(prim->verts[0].rgba);
+      for(j = 0; j <= lastel; ++j){  
+        prim = *(GL2PSprimitive**)gl2psListPointer(gro->ptrlist, j);
+        gl2ps->streamlength +=
+          gl2psPrintf("%f %f m %f %f l\n",
+                      prim->verts[0].xyz[0], prim->verts[0].xyz[1],
+                      prim->verts[0].xyz[0], prim->verts[0].xyz[1]);
+      }
+      gl2ps->streamlength += gl2psPrintf("S\n"); 
+      gl2ps->streamlength += gl2psPrintf("0 J\n");
+      break;
+    case GL2PS_LINE:
+      /* We try to use as few paths as possible to draw lines, in
+         order to get nice stippling even when the individual segments
+         are smaller than the stipple */
+      gl2ps->streamlength += gl2psPrintPDFLineWidth(prim->width);
+      gl2ps->streamlength += gl2psPrintPDFStrokeColor(prim->verts[0].rgba);
+      gl2ps->streamlength += gl2psPrintPostScriptDash(prim->pattern, prim->factor, "d");
+      /* start new path */
+      gl2ps->streamlength += 
+        gl2psPrintf("%f %f m\n", 
+                    prim->verts[0].xyz[0], prim->verts[0].xyz[1]);
+      
+      for(j = 1; j <= lastel; ++j){
+        prev = prim;
+        prim = *(GL2PSprimitive**)gl2psListPointer(gro->ptrlist, j);
+        if(!gl2psSamePosition(prim->verts[0].xyz, prev->verts[1].xyz)){
+          /* the starting point of the new segment does not match the
+             end point of the previous line, so we end the current
+             path and start a new one */
+          gl2ps->streamlength += 
+            gl2psPrintf("%f %f l\n", 
+                        prev->verts[1].xyz[0], prev->verts[1].xyz[1]);
+          gl2ps->streamlength += 
+            gl2psPrintf("%f %f m\n", 
+                        prim->verts[0].xyz[0], prim->verts[0].xyz[1]);
+        }
+        else{
+          /* the two segements are connected, so we just append to the
+             current path */
+          gl2ps->streamlength += 
+            gl2psPrintf("%f %f l\n",
+                        prim->verts[0].xyz[0], prim->verts[0].xyz[1]);
+        }
+      }
+      /* end last path */
+      gl2ps->streamlength += 
+        gl2psPrintf("%f %f l\n", 
+                    prim->verts[1].xyz[0], prim->verts[1].xyz[1]);
+      gl2ps->streamlength += gl2psPrintf("S\n");
+      break;
+    case GL2PS_TRIANGLE:
+      gl2psFillTriangleFromPrimitive(&t, prim, GL_TRUE);
+      gl2psSortOutTrianglePDFgroup(gro);
+      
+      /* No alpha and const color: Simple PDF draw orders  */
+      if(t.prop & T_CONST_COLOR && t.prop & T_ALPHA_1){         
+        gl2ps->streamlength += gl2psPrintPDFFillColor(t.vertex[0].rgba);        
+        for(j = 0; j <= lastel; ++j){  
+          prim = *(GL2PSprimitive**)gl2psListPointer(gro->ptrlist, j);
+          gl2psFillTriangleFromPrimitive(&t, prim, GL_FALSE);
+          gl2ps->streamlength 
+            += gl2psPrintf("%f %f m\n"
+                           "%f %f l\n"
+                           "%f %f l\n"
+                           "h f\n",
+                           t.vertex[0].xyz[0], t.vertex[0].xyz[1],
+                           t.vertex[1].xyz[0], t.vertex[1].xyz[1],
+                           t.vertex[2].xyz[0], t.vertex[2].xyz[1]);
+        }
+      }
+      /* Const alpha < 1 and const color: Simple PDF draw orders 
+         and an extra extended Graphics State for the alpha const */
+      else if(t.prop & T_CONST_COLOR && t.prop & T_ALPHA_LESS_1){               
+        gl2ps->streamlength += gl2psPrintf("q\n"
+                                           "/GS%d gs\n",
+                                           gro->gsno);
+        gl2ps->streamlength += gl2psPrintPDFFillColor(prim->verts[0].rgba);
+        for(j = 0; j <= lastel; ++j){  
+          prim = *(GL2PSprimitive**)gl2psListPointer(gro->ptrlist, j);
+          gl2psFillTriangleFromPrimitive(&t, prim, GL_FALSE);
+          gl2ps->streamlength 
+            += gl2psPrintf("%f %f m\n"
+                           "%f %f l\n"
+                           "%f %f l\n"
+                           "h f\n",
+                           t.vertex[0].xyz[0], t.vertex[0].xyz[1],
+                           t.vertex[1].xyz[0], t.vertex[1].xyz[1],
+                           t.vertex[2].xyz[0], t.vertex[2].xyz[1]);
+        }
+        gl2ps->streamlength += gl2psPrintf("Q\n");
+      }
+      /* Variable alpha and const color: Simple PDF draw orders 
+         and an extra extended Graphics State + Xobject + Shader 
+         object for the alpha mask */
+      else if(t.prop & T_CONST_COLOR && t.prop & T_VAR_ALPHA){          
+        gl2ps->streamlength += gl2psPrintf("q\n"
+                                           "/GS%d gs\n"
+                                           "/TrG%d Do\n",
+                                           gro->gsno, gro->trgroupno);
+        gl2ps->streamlength += gl2psPrintPDFFillColor(prim->verts[0].rgba);
+        for(j = 0; j <= lastel; ++j){  
+          prim = *(GL2PSprimitive**)gl2psListPointer(gro->ptrlist, j);
+          gl2psFillTriangleFromPrimitive(&t, prim, GL_FALSE);
+          gl2ps->streamlength 
+            += gl2psPrintf("%f %f m\n"
+                           "%f %f l\n"
+                           "%f %f l\n"
+                           "h f\n",
+                           t.vertex[0].xyz[0], t.vertex[0].xyz[1],
+                           t.vertex[1].xyz[0], t.vertex[1].xyz[1],
+                           t.vertex[2].xyz[0], t.vertex[2].xyz[1]);
+        }
+        gl2ps->streamlength += gl2psPrintf("Q\n");
+      }
+      /* Variable color and no alpha: Shader Object for the colored
+         triangle(s) */
+      else if(t.prop & T_VAR_COLOR && t.prop & T_ALPHA_1){              
+        gl2ps->streamlength += gl2psPrintf("/Sh%d sh\n", gro->shno);
+      }
+      /* Variable color and const alpha < 1: Shader Object for the 
+         colored triangle(s) and an extra extended Graphics State 
+         for the alpha const */
+      else if(t.prop & T_VAR_COLOR && t.prop & T_ALPHA_LESS_1){         
+        gl2ps->streamlength += gl2psPrintf("q\n"
+                                           "/GS%d gs\n"
+                                           "/Sh%d sh\n"
+                                           "Q\n",
+                                           gro->gsno, gro->shno);
+      }
+      /* Variable alpha and color: Shader Object for the colored 
+         triangle(s) and an extra extended Graphics State 
+         + Xobject + Shader object for the alpha mask */
+      else if(t.prop & T_VAR_COLOR && t.prop & T_VAR_ALPHA){            
+        gl2ps->streamlength += gl2psPrintf("q\n"
+                                           "/GS%d gs\n"
+                                           "/TrG%d Do\n"
+                                           "/Sh%d sh\n"
+                                           "Q\n",
+                                           gro->gsno, gro->trgroupno, gro->shno);
+      }
+      break;
+    case GL2PS_PIXMAP:
+      for(j = 0; j <= lastel; ++j){
+        prim = *(GL2PSprimitive**)gl2psListPointer(gro->ptrlist, j);
+        gl2psPutPDFImage(prim->data.image, gro->imno, prim->verts[0].xyz[0], 
+                         prim->verts[0].xyz[1]);
+      }
+      break;
+    case GL2PS_TEXT:
+      for(j = 0; j <= lastel; ++j){  
+        prim = *(GL2PSprimitive**)gl2psListPointer(gro->ptrlist, j);
+        gl2ps->streamlength += gl2psPrintPDFFillColor(prim->verts[0].rgba);
+        gl2psPutPDFText(prim->data.text, gro->fontno, prim->verts[0].xyz[0],
+                        prim->verts[0].xyz[1]);
+      }
+      break;
+    default:
+      break;
+    } 
+  }
+}
+
+/* Graphics State names */
+
+static int gl2psPDFgroupListWriteGStateResources(void)
+{
+  GL2PSpdfgroup *gro;
+  int offs = 0;
+  int i;
+
+  offs += fprintf(gl2ps->stream,
+                  "/ExtGState\n" 
+                  "<<\n"
+                  "/GSa 7 0 R\n");
+  for(i = 0; i < gl2psListNbr(gl2ps->pdfgrouplist); ++i){  
+    gro = (GL2PSpdfgroup*)gl2psListPointer(gl2ps->pdfgrouplist, i); 
+    if(gro->gsno >= 0)
+      offs += fprintf(gl2ps->stream, "/GS%d %d 0 R\n", gro->gsno, gro->gsobjno);
+  }
+  offs += fprintf(gl2ps->stream, ">>\n"); 
+  return offs;
+}
+
+/* Main Shader names */
+
+static int gl2psPDFgroupListWriteShaderResources(void)
+{
+  GL2PSpdfgroup *gro;
+  int offs = 0;
+  int i;
+
+  offs += fprintf(gl2ps->stream,
+                  "/Shading\n"
+                  "<<\n");
+  for(i = 0; i < gl2psListNbr(gl2ps->pdfgrouplist); ++i){  
+    gro = (GL2PSpdfgroup*)gl2psListPointer(gl2ps->pdfgrouplist, i); 
+    if(gro->shno >= 0)
+      offs += fprintf(gl2ps->stream, "/Sh%d %d 0 R\n", gro->shno, gro->shobjno);
+    if(gro->maskshno >= 0)
+      offs += fprintf(gl2ps->stream, "/TrSh%d %d 0 R\n", gro->maskshno, gro->maskshobjno);
+  }
+  offs += fprintf(gl2ps->stream,">>\n");  
+  return offs;
+}
+
+/* Images & Mask Shader XObject names */
+
+static int gl2psPDFgroupListWriteXObjectResources(void)
+{
+  int i;
+  GL2PSprimitive *p = NULL;
+  GL2PSpdfgroup *gro;
+  int offs = 0;
+
+  offs += fprintf(gl2ps->stream,
+                  "/XObject\n"
+                  "<<\n");
+
+  for(i = 0; i < gl2psListNbr(gl2ps->pdfgrouplist); ++i){  
+    gro = (GL2PSpdfgroup*)gl2psListPointer(gl2ps->pdfgrouplist, i); 
+    if(!gl2psListNbr(gro->ptrlist))
+      continue;
+    p = *(GL2PSprimitive**)gl2psListPointer(gro->ptrlist, 0);
+    switch(p->type){
+    case GL2PS_PIXMAP:
+      gro->imobjno = gl2ps->objects_stack++;
+      if(GL_RGBA == p->data.image->format)  /* reserve one object for image mask */
+        gl2ps->objects_stack++;
+      offs += fprintf(gl2ps->stream, "/Im%d %d 0 R\n", gro->imno, gro->imobjno);
+    case GL2PS_TRIANGLE:
+      if(gro->trgroupno >=0)
+        offs += fprintf(gl2ps->stream, "/TrG%d %d 0 R\n", gro->trgroupno, gro->trgroupobjno);
+      break;
+    default:
+      break;
+    }
+  }
+  offs += fprintf(gl2ps->stream,">>\n");
+  return offs;
+}
+
+/* Font names */
+
+static int gl2psPDFgroupListWriteFontResources(void)
+{
+  int i;
+  GL2PSpdfgroup *gro;
+  int offs = 0;
+
+  offs += fprintf(gl2ps->stream, "/Font\n<<\n");
+
+  for(i = 0; i < gl2psListNbr(gl2ps->pdfgrouplist); ++i){  
+    gro = (GL2PSpdfgroup*)gl2psListPointer(gl2ps->pdfgrouplist, i); 
+    if(gro->fontno < 0)
+      continue;
+    gro->fontobjno = gl2ps->objects_stack++;
+    offs += fprintf(gl2ps->stream, "/F%d %d 0 R\n", gro->fontno, gro->fontobjno);
+  }
+  offs += fprintf(gl2ps->stream, ">>\n");
+
+  return offs;
+}
+
+static void gl2psPDFgroupListDelete(void)
+{
+  int i;
+  GL2PSpdfgroup *gro = NULL;
+  
+  if(!gl2ps->pdfgrouplist)
+    return;
+
+  for(i = 0; i < gl2psListNbr(gl2ps->pdfgrouplist); ++i){ 
+    gro = (GL2PSpdfgroup*)gl2psListPointer(gl2ps->pdfgrouplist,i);
+    gl2psListDelete(gro->ptrlist);
+  }
+
+  gl2psListDelete(gl2ps->pdfgrouplist);
+  gl2ps->pdfgrouplist = NULL;
+}
+
+/* Print 1st PDF object - file info */
+
+static int gl2psPrintPDFInfo(void)
+{
+  int offs;
+  time_t now;
+  struct tm *newtime;
+  
+  time(&now);
+  newtime = gmtime(&now);
+  
+  offs = fprintf(gl2ps->stream,
+                 "1 0 obj\n"
+                 "<<\n"
+                 "/Title (%s)\n"
+                 "/Creator (GL2PS %d.%d.%d%s, %s)\n"
+                 "/Producer (%s)\n",
+                 gl2ps->title, GL2PS_MAJOR_VERSION, GL2PS_MINOR_VERSION,
+                 GL2PS_PATCH_VERSION, GL2PS_EXTRA_VERSION, GL2PS_COPYRIGHT,
+                 gl2ps->producer);
+  
+  if(!newtime){
+    offs += fprintf(gl2ps->stream, 
+                    ">>\n"
+                    "endobj\n");
+    return offs;
+  }
+  
+  offs += fprintf(gl2ps->stream, 
+                  "/CreationDate (D:%d%02d%02d%02d%02d%02d)\n"
+                  ">>\n"
+                  "endobj\n",
+                  newtime->tm_year+1900, 
+                  newtime->tm_mon+1, 
+                  newtime->tm_mday,
+                  newtime->tm_hour,
+                  newtime->tm_min,
+                  newtime->tm_sec);
+  return offs;
+}
+
+/* Create catalog and page structure - 2nd and 3th PDF object */
+
+static int gl2psPrintPDFCatalog(void)
+{
+  return fprintf(gl2ps->stream, 
+                 "2 0 obj\n"
+                 "<<\n"
+                 "/Type /Catalog\n"
+                 "/Pages 3 0 R\n"
+                 ">>\n"
+                 "endobj\n");
+}
+
+static int gl2psPrintPDFPages(void)
+{
+  return fprintf(gl2ps->stream, 
+                 "3 0 obj\n"
+                 "<<\n" 
+                 "/Type /Pages\n"
+                 "/Kids [6 0 R]\n"
+                 "/Count 1\n"
+                 ">>\n"
+                 "endobj\n");
+}
+
+/* Open stream for data - graphical objects, fonts etc. PDF object 4 */
+
+static int gl2psOpenPDFDataStream(void)
+{
+  int offs = 0;
+  
+  offs += fprintf(gl2ps->stream, 
+                  "4 0 obj\n"
+                  "<<\n" 
+                  "/Length 5 0 R\n" );
+  offs += gl2psPrintPDFCompressorType();
+  offs += fprintf(gl2ps->stream, 
+                  ">>\n"
+                  "stream\n");
+  return offs;
+}
+
+/* Stream setup - Graphics state, fill background if allowed */
+
+static int gl2psOpenPDFDataStreamWritePreface(void)
+{
+  int offs;
+
+  offs = gl2psPrintf("/GSa gs\n");
+  
+  if(gl2ps->options & GL2PS_DRAW_BACKGROUND){
+    offs += gl2psPrintPDFFillColor(gl2ps->bgcolor);
+    offs += gl2psPrintf("%d %d %d %d re\n",
+                        (int)gl2ps->viewport[0], (int)gl2ps->viewport[1],
+                        (int)gl2ps->viewport[2], (int)gl2ps->viewport[3]);
+    offs += gl2psPrintf("f\n");  
+  }
+  return offs;
+}
+
+/* Use the functions above to create the first part of the PDF*/
+
+static void gl2psPrintPDFHeader(void)
+{
+  int offs = 0;
+  gl2ps->pdfprimlist = gl2psListCreate(500, 500, sizeof(GL2PSprimitive*));
+  gl2psPDFstacksInit();
+
+  gl2ps->xreflist = (int*)gl2psMalloc(sizeof(int) * gl2ps->objects_stack); 
+
+#if defined(GL2PS_HAVE_ZLIB)
+  if(gl2ps->options & GL2PS_COMPRESS){
+    gl2psSetupCompress();
+  }
+#endif    
+  gl2ps->xreflist[0] = 0;
+  offs += fprintf(gl2ps->stream, "%%PDF-1.4\n");
+  gl2ps->xreflist[1] = offs;
+  
+  offs += gl2psPrintPDFInfo();
+  gl2ps->xreflist[2] = offs;
+  
+  offs += gl2psPrintPDFCatalog();
+  gl2ps->xreflist[3] = offs;
+  
+  offs += gl2psPrintPDFPages();
+  gl2ps->xreflist[4] = offs;
+  
+  offs += gl2psOpenPDFDataStream();
+  gl2ps->xreflist[5] = offs; /* finished in gl2psPrintPDFFooter */
+  gl2ps->streamlength = gl2psOpenPDFDataStreamWritePreface();
+}
+
+/* The central primitive drawing */
+
+static void gl2psPrintPDFPrimitive(void *data)
+{
+  GL2PSprimitive *prim = *(GL2PSprimitive**)data;
+
+  if((gl2ps->options & GL2PS_OCCLUSION_CULL) && prim->culled) 
+    return;
+
+  prim = gl2psCopyPrimitive(prim); /* deep copy */
+  gl2psListAdd(gl2ps->pdfprimlist, &prim);
+}
+
+/* close stream and ... */
+
+static int gl2psClosePDFDataStream(void)
+{
+  int offs = 0;
+ 
+#if defined(GL2PS_HAVE_ZLIB)
+  if(gl2ps->options & GL2PS_COMPRESS){
+    if(Z_OK != gl2psDeflate())
+      gl2psMsg(GL2PS_ERROR, "Zlib deflate error");
+    else
+      fwrite(gl2ps->compress->dest, gl2ps->compress->destLen, 1, gl2ps->stream);
+    gl2ps->streamlength += gl2ps->compress->destLen;
+    
+    offs += gl2ps->streamlength;
+    gl2psFreeCompress();
+  }
+#endif 
+  
+  offs += fprintf(gl2ps->stream, 
+                  "endstream\n"
+                  "endobj\n");
+  return offs;
+}
+
+/* ... write the now known length object */
+
+static int gl2psPrintPDFDataStreamLength(int val)
+{
+  return fprintf(gl2ps->stream,
+                 "5 0 obj\n"
+                 "%d\n"
+                 "endobj\n", val);
+}
+
+/* Put the info created before in PDF objects */
+
+static int gl2psPrintPDFOpenPage(void)
+{
+  int offs;
+  
+  /* Write fixed part */
+  
+  offs = fprintf(gl2ps->stream, 
+                 "6 0 obj\n"
+                 "<<\n" 
+                 "/Type /Page\n"
+                 "/Parent 3 0 R\n"
+                 "/MediaBox [%d %d %d %d]\n",
+                 (int)gl2ps->viewport[0], (int)gl2ps->viewport[1],
+                 (int)gl2ps->viewport[2], (int)gl2ps->viewport[3]);
+  
+  if(gl2ps->options & GL2PS_LANDSCAPE)
+    offs += fprintf(gl2ps->stream, "/Rotate -90\n");
+  
+  offs += fprintf(gl2ps->stream,
+                  "/Contents 4 0 R\n"
+                  "/Resources\n" 
+                  "<<\n" 
+                  "/ProcSet [/PDF /Text /ImageB /ImageC]  %%/ImageI\n");
+  
+  return offs;
+
+  /* End fixed part, proceeds in gl2psPDFgroupListWriteVariableResources() */
+}
+
+static int gl2psPDFgroupListWriteVariableResources(void)
+{
+  int offs = 0;
+  
+  /* a) Graphics States for shader alpha masks*/
+  offs += gl2psPDFgroupListWriteGStateResources();  
+  
+  /* b) Shader and shader masks */ 
+  offs += gl2psPDFgroupListWriteShaderResources();  
+ 
+  /* c) XObjects (Images & Shader Masks) */
+  offs += gl2psPDFgroupListWriteXObjectResources();
+  
+  /* d) Fonts */
+  offs += gl2psPDFgroupListWriteFontResources();
+  
+  /* End resources and page */
+  offs += fprintf(gl2ps->stream,
+                  ">>\n"
+                  ">>\n"
+                  "endobj\n");
+  return offs;
+}
+
+/* Standard Graphics State */
+
+static int gl2psPrintPDFGSObject(void)
+{
+  return fprintf(gl2ps->stream,
+                 "7 0 obj\n"
+                 "<<\n"
+                 "/Type /ExtGState\n"
+                 "/SA false\n"
+                 "/SM 0.02\n"
+                 "/OP false\n"
+                 "/op false\n"
+                 "/OPM 0\n"
+                 "/BG2 /Default\n"
+                 "/UCR2 /Default\n"
+                 "/TR2 /Default\n"
+                 ">>\n"
+                 "endobj\n");
+}
+
+/* Put vertex' edge flag (8bit) and coordinates (32bit) in shader stream */
+
+static int gl2psPrintPDFShaderStreamDataCoord(GL2PSvertex *vertex, 
+                                              size_t (*action)(unsigned long data, 
+                                                               size_t size), 
+                                              GLfloat dx, GLfloat dy, 
+                                              GLfloat xmin, GLfloat ymin)
+{
+  int offs = 0;
+  unsigned long imap;
+  GLfloat diff;
+  double dmax = ~1UL;
+  char edgeflag = 0;
+
+  /* FIXME: temp bux fix for 64 bit archs: */
+  if(sizeof(unsigned long) == 8) dmax = dmax - 2048.;
+
+  offs += (*action)(edgeflag, 1);
+
+  /* The Shader stream in PDF requires to be in a 'big-endian'
+     order */
+    
+  if(GL2PS_ZERO(dx * dy)){
+    offs += (*action)(0, 4);
+    offs += (*action)(0, 4);
+  }
+  else{
+    diff = (vertex->xyz[0] - xmin) / dx;
+    if(diff > 1)
+      diff = 1.0F;
+    else if(diff < 0)
+      diff = 0.0F;
+    imap = (unsigned long)(diff * dmax);
+    offs += (*action)(imap, 4);
+      
+    diff = (vertex->xyz[1] - ymin) / dy;
+    if(diff > 1)
+      diff = 1.0F;
+    else if(diff < 0)
+      diff = 0.0F;
+    imap = (unsigned long)(diff * dmax);
+    offs += (*action)(imap, 4);
+  }
+  
+  return offs;
+}
+
+/* Put vertex' rgb value (8bit for every component) in shader stream */
+
+static int gl2psPrintPDFShaderStreamDataRGB(GL2PSvertex *vertex,
+                                            size_t (*action)(unsigned long data, 
+                                                             size_t size))
+{
+  int offs = 0;
+  unsigned long imap;
+  double dmax = ~1UL;
+
+  /* FIXME: temp bux fix for 64 bit archs: */
+  if(sizeof(unsigned long) == 8) dmax = dmax - 2048.;
+
+  imap = (unsigned long)((vertex->rgba[0]) * dmax);
+  offs += (*action)(imap, 1);
+    
+  imap = (unsigned long)((vertex->rgba[1]) * dmax);
+  offs += (*action)(imap, 1);
+    
+  imap = (unsigned long)((vertex->rgba[2]) * dmax);
+  offs += (*action)(imap, 1);
+  
+  return offs;
+}
+
+/* Put vertex' alpha (8/16bit) in shader stream */
+
+static int gl2psPrintPDFShaderStreamDataAlpha(GL2PSvertex *vertex, 
+                                              size_t (*action)(unsigned long data, 
+                                                               size_t size),
+                                              int sigbyte)
+{
+  int offs = 0;
+  unsigned long imap;
+  double dmax = ~1UL;
+
+  /* FIXME: temp bux fix for 64 bit archs: */
+  if(sizeof(unsigned long) == 8) dmax = dmax - 2048.;
+
+  if(sigbyte != 8 && sigbyte != 16)
+    sigbyte = 8;
+        
+  sigbyte /= 8;
+  
+  imap = (unsigned long)((vertex->rgba[3]) * dmax);
+  
+  offs += (*action)(imap, sigbyte);
+  
+  return offs;
+}
+
+/* Put a triangles raw data in shader stream */
+
+static int gl2psPrintPDFShaderStreamData(GL2PStriangle *triangle, 
+                                         GLfloat dx, GLfloat dy, 
+                                         GLfloat xmin, GLfloat ymin,
+                                         size_t (*action)(unsigned long data, 
+                                                          size_t size),
+                                         int gray)
+{
+  int i, offs = 0;
+  GL2PSvertex v;
+  
+  if(gray && gray != 8 && gray != 16)
+    gray = 8;
+  
+  for(i = 0; i < 3; ++i){
+    offs += gl2psPrintPDFShaderStreamDataCoord(&triangle->vertex[i], action,
+                                               dx, dy, xmin, ymin);
+    if(gray){ 
+      v = triangle->vertex[i];
+      offs += gl2psPrintPDFShaderStreamDataAlpha(&v, action, gray); 
+    }
+    else{
+      offs += gl2psPrintPDFShaderStreamDataRGB(&triangle->vertex[i], action);
+    }
+  }
+  
+  return offs;
+}
+
+static void gl2psPDFRectHull(GLfloat *xmin, GLfloat *xmax, 
+                             GLfloat *ymin, GLfloat *ymax, 
+                             GL2PStriangle *triangles, int cnt)
+{
+  int i, j;
+
+  *xmin = triangles[0].vertex[0].xyz[0];
+  *xmax = triangles[0].vertex[0].xyz[0];
+  *ymin = triangles[0].vertex[0].xyz[1];
+  *ymax = triangles[0].vertex[0].xyz[1];
+  
+  for(i = 0; i < cnt; ++i){
+    for(j = 0; j < 3; ++j){
+      if(*xmin > triangles[i].vertex[j].xyz[0])
+        *xmin = triangles[i].vertex[j].xyz[0];
+      if(*xmax < triangles[i].vertex[j].xyz[0])
+        *xmax = triangles[i].vertex[j].xyz[0];
+      if(*ymin > triangles[i].vertex[j].xyz[1])
+        *ymin = triangles[i].vertex[j].xyz[1];
+      if(*ymax < triangles[i].vertex[j].xyz[1])
+        *ymax = triangles[i].vertex[j].xyz[1];
+    }
+  }
+}
+
+/* Writes shaded triangle 
+   gray == 0 means write RGB triangles
+   gray == 8             8bit-grayscale (for alpha masks)
+   gray == 16            16bit-grayscale (for alpha masks) */
+
+static int gl2psPrintPDFShader(int obj, GL2PStriangle *triangles, 
+                               int size, int gray)
+{
+  int i, offs = 0, vertexbytes, done = 0;
+  GLfloat xmin, xmax, ymin, ymax;
+        
+  switch(gray){
+  case 0:
+    vertexbytes = 1+4+4+1+1+1;
+    break;
+  case 8:
+    vertexbytes = 1+4+4+1;
+    break;
+  case 16:
+    vertexbytes = 1+4+4+2;
+    break;
+  default:
+    gray = 8;
+    vertexbytes = 1+4+4+1;
+    break;
+  }
+  
+  gl2psPDFRectHull(&xmin, &xmax, &ymin, &ymax, triangles, size);
+  
+  offs += fprintf(gl2ps->stream,
+                  "%d 0 obj\n"
+                  "<< "
+                  "/ShadingType 4 "
+                  "/ColorSpace %s "
+                  "/BitsPerCoordinate 32 "
+                  "/BitsPerComponent %d "
+                  "/BitsPerFlag 8 "
+                  "/Decode [%f %f %f %f 0 1 %s] ",
+                  obj,
+                  (gray) ? "/DeviceGray" : "/DeviceRGB", 
+                  (gray) ? gray : 8,
+                  xmin, xmax, ymin, ymax,
+                  (gray) ? "" : "0 1 0 1");
+  
+#if defined(GL2PS_HAVE_ZLIB)
+  if(gl2ps->options & GL2PS_COMPRESS){
+    gl2psAllocCompress(vertexbytes * size * 3);
+
+    for(i = 0; i < size; ++i)
+      gl2psPrintPDFShaderStreamData(&triangles[i],
+                                    xmax-xmin, ymax-ymin, xmin, ymin, 
+                                    gl2psWriteBigEndianCompress, gray);
+
+    if(Z_OK == gl2psDeflate() && 23 + gl2ps->compress->destLen < gl2ps->compress->srcLen){
+      offs += gl2psPrintPDFCompressorType();
+      offs += fprintf(gl2ps->stream,
+                      "/Length %d "
+                      ">>\n"
+                      "stream\n",
+                      (int)gl2ps->compress->destLen);
+      offs += gl2ps->compress->destLen * fwrite(gl2ps->compress->dest, 
+                                                gl2ps->compress->destLen, 
+                                                1, gl2ps->stream);
+      done = 1;
+    }
+    gl2psFreeCompress();
+  }
+#endif
+
+  if(!done){
+    /* no compression, or too long after compression, or compress error
+       -> write non-compressed entry */
+    offs += fprintf(gl2ps->stream,
+                    "/Length %d "
+                    ">>\n"
+                    "stream\n",
+                    vertexbytes * 3 * size);
+    for(i = 0; i < size; ++i)
+      offs += gl2psPrintPDFShaderStreamData(&triangles[i],
+                                            xmax-xmin, ymax-ymin, xmin, ymin,
+                                            gl2psWriteBigEndian, gray);
+  }
+  
+  offs += fprintf(gl2ps->stream,
+                  "\nendstream\n"
+                  "endobj\n");
+  
+  return offs;
+}
+
+/* Writes a XObject for a shaded triangle mask */
+
+static int gl2psPrintPDFShaderMask(int obj, int childobj)
+{
+  int offs = 0, len;
+  
+  offs += fprintf(gl2ps->stream,
+                  "%d 0 obj\n"
+                  "<<\n"
+                  "/Type /XObject\n"
+                  "/Subtype /Form\n"
+                  "/BBox [ %d %d %d %d ]\n"
+                  "/Group \n<<\n/S /Transparency /CS /DeviceRGB\n"
+                  ">>\n",
+                  obj,
+                  (int)gl2ps->viewport[0], (int)gl2ps->viewport[1],
+                  (int)gl2ps->viewport[2], (int)gl2ps->viewport[3]);
+  
+  len = (childobj>0) 
+    ? strlen("/TrSh sh\n") + (int)log10((double)childobj)+1
+    : strlen("/TrSh0 sh\n"); 
+  
+  offs += fprintf(gl2ps->stream,
+                  "/Length %d\n"
+                  ">>\n"
+                  "stream\n",
+                  len);
+  offs += fprintf(gl2ps->stream,
+                  "/TrSh%d sh\n",
+                  childobj);
+  offs += fprintf(gl2ps->stream,
+                  "endstream\n"
+                  "endobj\n");
+  
+  return offs;
+}
+
+/* Writes a Extended graphics state for a shaded triangle mask if
+   simplealpha ist true the childobj argument is ignored and a /ca
+   statement will be written instead */
+
+static int gl2psPrintPDFShaderExtGS(int obj, int childobj)
+{
+  int offs = 0;
+  
+  offs += fprintf(gl2ps->stream,
+                  "%d 0 obj\n"
+                  "<<\n",
+                  obj);
+  
+  offs += fprintf(gl2ps->stream,
+                  "/SMask << /S /Alpha /G %d 0 R >> ",
+                  childobj);
+  
+  offs += fprintf(gl2ps->stream,
+                  ">>\n"
+                  "endobj\n");
+  return offs;
+}
+
+/* a simple graphics state */
+
+static int gl2psPrintPDFShaderSimpleExtGS(int obj, GLfloat alpha)
+{
+  int offs = 0;
+  
+  offs += fprintf(gl2ps->stream,
+                  "%d 0 obj\n"
+                  "<<\n"
+                  "/ca %g"
+                  ">>\n"
+                  "endobj\n",
+                  obj, alpha);
+  return offs;
+}
+
+/* Similar groups of functions for pixmaps and text */
+
+static int gl2psPrintPDFPixmapStreamData(GL2PSimage *im,
+                                         size_t (*action)(unsigned long data, 
+                                                          size_t size), 
+                                         int gray)
+{
+  int x, y;
+  GLfloat r, g, b, a;
+
+  if(im->format != GL_RGBA && gray)
+    return 0;
+
+  if(gray && gray !=8 && gray != 16)
+    gray = 8;
+
+  gray /= 8;
+  
+  for(y = 0; y < im->height; ++y){
+    for(x = 0; x < im->width; ++x){
+      a = gl2psGetRGB(im, x, y, &r, &g, &b);
+      if(im->format == GL_RGBA && gray){
+        (*action)((unsigned long)(a*255) << 24, gray);
+      }
+      else{
+        (*action)((unsigned long)(r*255) << 24, 1);
+        (*action)((unsigned long)(g*255) << 24, 1);
+        (*action)((unsigned long)(b*255) << 24, 1);
+      }
+    }
+  }
+
+  switch(gray){
+  case 0: return 3 * im->width * im->height;
+  case 1: return im->width * im->height;
+  case 2: return 2 * im->width * im->height;
+  default: return 3 * im->width * im->height;
+  }
+}
+
+static int gl2psPrintPDFPixmap(int obj, int childobj, GL2PSimage *im, int gray)
+{
+  int offs = 0, done = 0, sigbytes = 3;
+
+  if(gray && gray !=8 && gray != 16)
+    gray = 8;
+  
+  if(gray)
+    sigbytes = gray / 8; 
+  
+  offs += fprintf(gl2ps->stream,
+                  "%d 0 obj\n"
+                  "<<\n"
+                  "/Type /XObject\n"
+                  "/Subtype /Image\n"
+                  "/Width %d\n"
+                  "/Height %d\n"
+                  "/ColorSpace %s \n"
+                  "/BitsPerComponent 8\n",
+                  obj,
+                  (int)im->width, (int)im->height,
+                  (gray) ? "/DeviceGray" : "/DeviceRGB" );
+  if(GL_RGBA == im->format && gray == 0){
+    offs += fprintf(gl2ps->stream,
+                    "/SMask %d 0 R\n",
+                    childobj);
+  }
+  
+#if defined(GL2PS_HAVE_ZLIB)
+  if(gl2ps->options & GL2PS_COMPRESS){
+    gl2psAllocCompress((int)(im->width * im->height * sigbytes));
+    
+    gl2psPrintPDFPixmapStreamData(im, gl2psWriteBigEndianCompress, gray);
+    
+    if(Z_OK == gl2psDeflate() && 23 + gl2ps->compress->destLen < gl2ps->compress->srcLen){
+      offs += gl2psPrintPDFCompressorType();
+      offs += fprintf(gl2ps->stream,
+                      "/Length %d "
+                      ">>\n"
+                      "stream\n",
+                      (int)gl2ps->compress->destLen);
+      offs += gl2ps->compress->destLen * fwrite(gl2ps->compress->dest, gl2ps->compress->destLen,
+                                                1, gl2ps->stream);
+      done = 1;
+    }
+    gl2psFreeCompress();
+  }
+#endif
+  
+  if(!done){
+    /* no compression, or too long after compression, or compress error
+       -> write non-compressed entry */
+    offs += fprintf(gl2ps->stream,
+                    "/Length %d "
+                    ">>\n"
+                    "stream\n",
+                    (int)(im->width * im->height * sigbytes));
+    offs += gl2psPrintPDFPixmapStreamData(im, gl2psWriteBigEndian, gray);
+  }
+  
+  offs += fprintf(gl2ps->stream,
+                  "\nendstream\n"
+                  "endobj\n");
+  
+  return offs;
+}
+
+static int gl2psPrintPDFText(int obj, GL2PSstring *s, int fontnumber)
+{
+  int offs = 0;
+  
+  offs += fprintf(gl2ps->stream,
+                  "%d 0 obj\n"
+                  "<<\n"
+                  "/Type /Font\n"
+                  "/Subtype /Type1\n"
+                  "/Name /F%d\n"
+                  "/BaseFont /%s\n"
+                  "/Encoding /MacRomanEncoding\n"
+                  ">>\n"
+                  "endobj\n",
+                  obj, fontnumber, s->fontname);
+  return offs;
+}
+
+/* Write the physical objects */
+
+static int gl2psPDFgroupListWriteObjects(int entryoffs)
+{
+  int i,j;
+  GL2PSprimitive *p = NULL;
+  GL2PSpdfgroup *gro;
+  int offs = entryoffs;
+  GL2PStriangle *triangles;
+  int size = 0;
+
+  if(!gl2ps->pdfgrouplist)
+    return offs;
+  
+  for(i = 0; i < gl2psListNbr(gl2ps->pdfgrouplist); ++i){  
+    gro = (GL2PSpdfgroup*)gl2psListPointer(gl2ps->pdfgrouplist, i); 
+    if(!gl2psListNbr(gro->ptrlist))
+      continue;
+    p = *(GL2PSprimitive**)gl2psListPointer(gro->ptrlist, 0);
+    switch(p->type){
+    case GL2PS_POINT:
+      break;
+    case GL2PS_LINE:
+      break;
+    case GL2PS_TRIANGLE:
+      size = gl2psListNbr(gro->ptrlist);
+      triangles = (GL2PStriangle*)gl2psMalloc(sizeof(GL2PStriangle) * size);
+      for(j = 0; j < size; ++j){  
+        p = *(GL2PSprimitive**)gl2psListPointer(gro->ptrlist, j);
+        gl2psFillTriangleFromPrimitive(&triangles[j], p, GL_TRUE);
+      }
+      if(triangles[0].prop & T_VAR_COLOR){
+        gl2ps->xreflist[gro->shobjno] = offs;
+        offs += gl2psPrintPDFShader(gro->shobjno, triangles, size, 0);
+      }
+      if(triangles[0].prop & T_ALPHA_LESS_1){
+        gl2ps->xreflist[gro->gsobjno] = offs;
+        offs += gl2psPrintPDFShaderSimpleExtGS(gro->gsobjno, triangles[0].vertex[0].rgba[3]);
+      }
+      if(triangles[0].prop & T_VAR_ALPHA){
+        gl2ps->xreflist[gro->gsobjno] = offs;
+        offs += gl2psPrintPDFShaderExtGS(gro->gsobjno, gro->trgroupobjno);
+        gl2ps->xreflist[gro->trgroupobjno] = offs;
+        offs += gl2psPrintPDFShaderMask(gro->trgroupobjno, gro->maskshno);
+        gl2ps->xreflist[gro->maskshobjno] = offs;
+        offs += gl2psPrintPDFShader(gro->maskshobjno, triangles, size, 8);
+      }
+      gl2psFree(triangles);
+      break;
+    case GL2PS_PIXMAP:
+      gl2ps->xreflist[gro->imobjno] = offs;
+      offs += gl2psPrintPDFPixmap(gro->imobjno, gro->imobjno+1, p->data.image, 0);
+      if(p->data.image->format == GL_RGBA){
+        gl2ps->xreflist[gro->imobjno+1] = offs;
+        offs += gl2psPrintPDFPixmap(gro->imobjno+1, -1, p->data.image, 8);
+      }
+      break;
+    case GL2PS_TEXT:
+      gl2ps->xreflist[gro->fontobjno] = offs;
+      offs += gl2psPrintPDFText(gro->fontobjno,p->data.text,gro->fontno);
+      break;
+    case GL2PS_SPECIAL :
+      /* alignment contains the format for which the special output text
+         is intended */
+      if(p->data.text->alignment == GL2PS_PDF)
+        offs += fprintf(gl2ps->stream, "%s\n", p->data.text->str);
+      break;
+    default:
+      break;
+    } 
+  }
+  return offs;
+}
+
+/* All variable data has been written at this point and all required
+   functioninality has been gathered, so we can write now file footer
+   with cross reference table and trailer */
+
+static void gl2psPrintPDFFooter(void)
+{
+  int i, offs;  
+
+  gl2psPDFgroupListInit();
+  gl2psPDFgroupListWriteMainStream();
+ 
+  offs = gl2ps->xreflist[5] + gl2ps->streamlength; 
+  offs += gl2psClosePDFDataStream();
+  gl2ps->xreflist[5] = offs;
+  
+  offs += gl2psPrintPDFDataStreamLength(gl2ps->streamlength);
+  gl2ps->xreflist[6] = offs;
+  gl2ps->streamlength = 0;
+  
+  offs += gl2psPrintPDFOpenPage();
+  offs += gl2psPDFgroupListWriteVariableResources();
+  gl2ps->xreflist = (int*)gl2psRealloc(gl2ps->xreflist,
+                                       sizeof(int) * (gl2ps->objects_stack + 1));
+  gl2ps->xreflist[7] = offs;
+  
+  offs += gl2psPrintPDFGSObject();
+  gl2ps->xreflist[8] = offs;
+  
+  gl2ps->xreflist[gl2ps->objects_stack] = 
+    gl2psPDFgroupListWriteObjects(gl2ps->xreflist[8]);
+
+  /* Start cross reference table. The file has to been opened in
+     binary mode to preserve the 20 digit string length! */
+  fprintf(gl2ps->stream,
+          "xref\n"
+          "0 %d\n"
+          "%010d 65535 f \n", gl2ps->objects_stack, 0);
+  
+  for(i = 1; i < gl2ps->objects_stack; ++i)
+    fprintf(gl2ps->stream, "%010d 00000 n \n", gl2ps->xreflist[i]);
+  
+  fprintf(gl2ps->stream,
+          "trailer\n"
+          "<<\n" 
+          "/Size %d\n"
+          "/Info 1 0 R\n"
+          "/Root 2 0 R\n"
+          ">>\n"
+          "startxref\n%d\n"
+          "%%%%EOF\n",
+          gl2ps->objects_stack, gl2ps->xreflist[gl2ps->objects_stack]);
+  
+  /* Free auxiliary lists and arrays */    
+  gl2psFree(gl2ps->xreflist);
+  gl2psListAction(gl2ps->pdfprimlist, gl2psFreePrimitive);
+  gl2psListDelete(gl2ps->pdfprimlist);
+  gl2psPDFgroupListDelete();
+  
+#if defined(GL2PS_HAVE_ZLIB)
+  if(gl2ps->options & GL2PS_COMPRESS){
+    gl2psFreeCompress();
+    gl2psFree(gl2ps->compress);
+    gl2ps->compress = NULL;
+  }
+#endif
+}
+
+/* PDF begin viewport */
+
+static void gl2psPrintPDFBeginViewport(GLint viewport[4])
+{
+  int offs = 0;
+  GLint index;
+  GLfloat rgba[4];
+  int x = viewport[0], y = viewport[1], w = viewport[2], h = viewport[3];
+  
+  glRenderMode(GL_FEEDBACK);
+  
+  if(gl2ps->header){
+    gl2psPrintPDFHeader();
+    gl2ps->header = GL_FALSE;
+  }
+
+  offs += gl2psPrintf("q\n");
+  
+  if(gl2ps->options & GL2PS_DRAW_BACKGROUND){
+    if(gl2ps->colormode == GL_RGBA || gl2ps->colorsize == 0){
+      glGetFloatv(GL_COLOR_CLEAR_VALUE, rgba);
+    }
+    else{
+      glGetIntegerv(GL_INDEX_CLEAR_VALUE, &index);
+      rgba[0] = gl2ps->colormap[index][0];
+      rgba[1] = gl2ps->colormap[index][1];
+      rgba[2] = gl2ps->colormap[index][2];
+      rgba[3] = 1.0F;
+    }
+    offs += gl2psPrintPDFFillColor(rgba);
+    offs += gl2psPrintf("%d %d %d %d re\n"
+                        "W\n"
+                        "f\n",
+                        x, y, w, h);
+  }
+  else{
+    offs += gl2psPrintf("%d %d %d %d re\n"
+                        "W\n"   
+                        "n\n",
+                        x, y, w, h);            
+  }
+  
+  gl2ps->streamlength += offs;
+}
+
+static GLint gl2psPrintPDFEndViewport(void)
+{
+  GLint res;
+  
+  res = gl2psPrintPrimitives();
+  gl2ps->streamlength += gl2psPrintf("Q\n");
+  return res;
+}
+
+static void gl2psPrintPDFFinalPrimitive(void)
+{
+}
+
+/* definition of the PDF backend */
+
+static GL2PSbackend gl2psPDF = {
+  gl2psPrintPDFHeader,
+  gl2psPrintPDFFooter,
+  gl2psPrintPDFBeginViewport,
+  gl2psPrintPDFEndViewport,
+  gl2psPrintPDFPrimitive,
+  gl2psPrintPDFFinalPrimitive,
+  "pdf",
+  "Portable Document Format"
+};
+
+/********************************************************************* 
+ *
+ * SVG routines
+ *
+ *********************************************************************/
+
+static void gl2psSVGGetCoordsAndColors(int n, GL2PSvertex *verts, 
+                                       GL2PSxyz *xyz, GL2PSrgba *rgba)
+{
+  int i, j;
+
+  for(i = 0; i < n; i++){
+    xyz[i][0] = verts[i].xyz[0];
+    xyz[i][1] = gl2ps->viewport[3] - verts[i].xyz[1];
+    xyz[i][2] = 0.0F;
+    for(j = 0; j < 4; j++)
+      rgba[i][j] = verts[i].rgba[j];
+  }
+}
+
+static void gl2psSVGGetColorString(GL2PSrgba rgba, char str[32])
+{
+  int r = (int)(255. * rgba[0]);
+  int g = (int)(255. * rgba[1]);
+  int b = (int)(255. * rgba[2]);
+  int rc = (r < 0) ? 0 : (r > 255) ? 255 : r;
+  int gc = (g < 0) ? 0 : (g > 255) ? 255 : g;
+  int bc = (b < 0) ? 0 : (b > 255) ? 255 : b;
+  sprintf(str, "#%2.2x%2.2x%2.2x", rc, gc, bc);
+}
+
+static void gl2psPrintSVGHeader(void)
+{
+  int x, y, width, height;
+  char col[32];
+  time_t now;
+  
+  time(&now);
+  
+  if (gl2ps->options & GL2PS_LANDSCAPE){
+    x = (int)gl2ps->viewport[1];
+    y = (int)gl2ps->viewport[0];
+    width = (int)gl2ps->viewport[3];
+    height = (int)gl2ps->viewport[2];
+  }
+  else{
+    x = (int)gl2ps->viewport[0];
+    y = (int)gl2ps->viewport[1];
+    width = (int)gl2ps->viewport[2];
+    height = (int)gl2ps->viewport[3];
+  }
+  
+  /* Compressed SVG files (.svgz) are simply gzipped SVG files */
+  gl2psPrintGzipHeader();
+  
+  gl2psPrintf("<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?>\n");
+  gl2psPrintf("<svg xmlns=\"http://www.w3.org/2000/svg\"\n");
+  gl2psPrintf("     xmlns:xlink=\"http://www.w3.org/1999/xlink\"\n"
+              "     width=\"%dpx\" height=\"%dpx\" viewBox=\"%d %d %d %d\">\n",
+              width, height, x, y, width, height);
+  gl2psPrintf("<title>%s</title>\n", gl2ps->title);
+  gl2psPrintf("<desc>\n");
+  gl2psPrintf("Creator: GL2PS %d.%d.%d%s, %s\n"
+              "For: %s\n"
+              "CreationDate: %s",
+              GL2PS_MAJOR_VERSION, GL2PS_MINOR_VERSION, GL2PS_PATCH_VERSION,
+              GL2PS_EXTRA_VERSION, GL2PS_COPYRIGHT, gl2ps->producer, ctime(&now));
+  gl2psPrintf("</desc>\n");
+  gl2psPrintf("<defs>\n");
+  gl2psPrintf("</defs>\n");
+
+  if(gl2ps->options & GL2PS_DRAW_BACKGROUND){
+    gl2psSVGGetColorString(gl2ps->bgcolor, col);
+    gl2psPrintf("<polygon fill=\"%s\" points=\"%d,%d %d,%d %d,%d %d,%d\"/>\n", col,
+                (int)gl2ps->viewport[0], (int)gl2ps->viewport[1], 
+                (int)gl2ps->viewport[2], (int)gl2ps->viewport[1], 
+                (int)gl2ps->viewport[2], (int)gl2ps->viewport[3], 
+                (int)gl2ps->viewport[0], (int)gl2ps->viewport[3]);
+  }
+
+  /* group all the primitives and disable antialiasing */
+  gl2psPrintf("<g shape-rendering=\"crispEdges\">\n");
+}
+
+static void gl2psPrintSVGSmoothTriangle(GL2PSxyz xyz[3], GL2PSrgba rgba[3])
+{
+  int i;
+  GL2PSxyz xyz2[3];
+  GL2PSrgba rgba2[3];
+  char col[32];
+
+  /* Apparently there is no easy way to do Gouraud shading in SVG
+     without explicitly pre-defining gradients, so for now we just do
+     recursive subdivision */
+
+  if(gl2psSameColorThreshold(3, rgba, gl2ps->threshold)){
+    gl2psSVGGetColorString(rgba[0], col);
+    gl2psPrintf("<polygon fill=\"%s\" ", col);
+    if(rgba[0][3] < 1.0F) gl2psPrintf("fill-opacity=\"%g\" ", rgba[0][3]);
+    gl2psPrintf("points=\"%g,%g %g,%g %g,%g\"/>\n", xyz[0][0], xyz[0][1], 
+                xyz[1][0], xyz[1][1], xyz[2][0], xyz[2][1]);
+  }
+  else{
+    /* subdivide into 4 subtriangles */
+    for(i = 0; i < 3; i++){
+      xyz2[0][i] = xyz[0][i]; 
+      xyz2[1][i] = 0.5F * (xyz[0][i] + xyz[1][i]);
+      xyz2[2][i] = 0.5F * (xyz[0][i] + xyz[2][i]);
+    }
+    for(i = 0; i < 4; i++){
+      rgba2[0][i] = rgba[0][i]; 
+      rgba2[1][i] = 0.5F * (rgba[0][i] + rgba[1][i]);
+      rgba2[2][i] = 0.5F * (rgba[0][i] + rgba[2][i]);
+    }
+    gl2psPrintSVGSmoothTriangle(xyz2, rgba2);
+    for(i = 0; i < 3; i++){
+      xyz2[0][i] = 0.5F * (xyz[0][i] + xyz[1][i]);
+      xyz2[1][i] = xyz[1][i]; 
+      xyz2[2][i] = 0.5F * (xyz[1][i] + xyz[2][i]);
+    }
+    for(i = 0; i < 4; i++){
+      rgba2[0][i] = 0.5F * (rgba[0][i] + rgba[1][i]);
+      rgba2[1][i] = rgba[1][i]; 
+      rgba2[2][i] = 0.5F * (rgba[1][i] + rgba[2][i]);
+    }
+    gl2psPrintSVGSmoothTriangle(xyz2, rgba2);
+    for(i = 0; i < 3; i++){
+      xyz2[0][i] = 0.5F * (xyz[0][i] + xyz[2][i]);
+      xyz2[1][i] = xyz[2][i]; 
+      xyz2[2][i] = 0.5F * (xyz[1][i] + xyz[2][i]);
+    }
+    for(i = 0; i < 4; i++){
+      rgba2[0][i] = 0.5F * (rgba[0][i] + rgba[2][i]);
+      rgba2[1][i] = rgba[2][i]; 
+      rgba2[2][i] = 0.5F * (rgba[1][i] + rgba[2][i]);
+    }
+    gl2psPrintSVGSmoothTriangle(xyz2, rgba2);
+    for(i = 0; i < 3; i++){
+      xyz2[0][i] = 0.5F * (xyz[0][i] + xyz[1][i]);
+      xyz2[1][i] = 0.5F * (xyz[1][i] + xyz[2][i]); 
+      xyz2[2][i] = 0.5F * (xyz[0][i] + xyz[2][i]);
+    }
+    for(i = 0; i < 4; i++){
+      rgba2[0][i] = 0.5F * (rgba[0][i] + rgba[1][i]);
+      rgba2[1][i] = 0.5F * (rgba[1][i] + rgba[2][i]); 
+      rgba2[2][i] = 0.5F * (rgba[0][i] + rgba[2][i]);
+    }
+    gl2psPrintSVGSmoothTriangle(xyz2, rgba2);
+  }
+}
+
+static void gl2psPrintSVGDash(GLushort pattern, GLint factor)
+{
+  int i, n, array[10];
+
+  if(!pattern || !factor) return; /* solid line */
+
+  gl2psParseStipplePattern(pattern, factor, &n, array);
+  gl2psPrintf("stroke-dasharray=\"");
+  for(i = 0; i < n; i++){
+    if(i) gl2psPrintf(",");
+    gl2psPrintf("%d", array[i]);
+  }
+  gl2psPrintf("\" ");
+}
+
+static void gl2psEndSVGLine(void)
+{
+  int i;
+  if(gl2ps->lastvertex.rgba[0] >= 0.){
+    gl2psPrintf("%g,%g\"/>\n", gl2ps->lastvertex.xyz[0], 
+                gl2ps->viewport[3] - gl2ps->lastvertex.xyz[1]);
+    for(i = 0; i < 3; i++)
+      gl2ps->lastvertex.xyz[i] = -1.;
+    for(i = 0; i < 4; i++)
+      gl2ps->lastvertex.rgba[i] = -1.;
+  }
+}
+
+static void gl2psPrintSVGPixmap(GLfloat x, GLfloat y, GL2PSimage *pixmap)
+{
+#if defined(GL2PS_HAVE_LIBPNG)
+  GL2PSlist *png;
+  unsigned char c;
+  int i;
+
+  /* The only image types supported by the SVG standard are JPEG, PNG
+     and SVG. Here we choose PNG, and since we want to embed the image
+     directly in the SVG stream (and not link to an external image
+     file), we need to encode the pixmap into PNG in memory, then
+     encode it into base64. */
+
+  png = gl2psListCreate(pixmap->width * pixmap->height * 3, 1000, 
+                        sizeof(unsigned char));
+  gl2psConvertPixmapToPNG(pixmap, png);
+  gl2psListEncodeBase64(png);
+  gl2psPrintf("<image x=\"%g\" y=\"%g\" width=\"%d\" height=\"%d\"\n",
+              x, y - pixmap->height, pixmap->width, pixmap->height);
+  gl2psPrintf("xlink:href=\"data:image/png;base64,");
+  for(i = 0; i < gl2psListNbr(png); i++){
+    gl2psListRead(png, i, &c);
+    gl2psPrintf("%c", c);
+  }
+  gl2psPrintf("\"/>\n");
+  gl2psListDelete(png);
+#else
+  gl2psMsg(GL2PS_WARNING, "GL2PS must be compiled with PNG support in "
+           "order to embed images in SVG streams");
+#endif
+}
+
+static void gl2psPrintSVGPrimitive(void *data)
+{
+  GL2PSprimitive *prim;
+  GL2PSxyz xyz[4];
+  GL2PSrgba rgba[4];
+  char col[32];
+  int newline;
+
+  prim = *(GL2PSprimitive**)data;
+
+  if((gl2ps->options & GL2PS_OCCLUSION_CULL) && prim->culled) return;
+
+  /* We try to draw connected lines as a single path to get nice line
+     joins and correct stippling. So if the primitive to print is not
+     a line we must first finish the current line (if any): */
+  if(prim->type != GL2PS_LINE) gl2psEndSVGLine();
+
+  gl2psSVGGetCoordsAndColors(prim->numverts, prim->verts, xyz, rgba);
+
+  switch(prim->type){
+  case GL2PS_POINT :
+    gl2psSVGGetColorString(rgba[0], col);
+    gl2psPrintf("<circle fill=\"%s\" ", col);
+    if(rgba[0][3] < 1.0F) gl2psPrintf("fill-opacity=\"%g\" ", rgba[0][3]);
+    gl2psPrintf("cx=\"%g\" cy=\"%g\" r=\"%g\"/>\n",
+                xyz[0][0], xyz[0][1], 0.5 * prim->width);
+    break;
+  case GL2PS_LINE :
+    if(!gl2psSamePosition(gl2ps->lastvertex.xyz, prim->verts[0].xyz) ||
+       !gl2psSameColor(gl2ps->lastrgba, prim->verts[0].rgba) ||
+       gl2ps->lastlinewidth != prim->width ||
+       gl2ps->lastpattern != prim->pattern ||
+       gl2ps->lastfactor != prim->factor){
+      /* End the current line if the new segment does not start where
+         the last one ended, or if the color, the width or the
+         stippling have changed (we will need to use multi-point
+         gradients for smooth-shaded lines) */
+      gl2psEndSVGLine();
+      newline = 1;
+    }
+    else{
+      newline = 0;
+    }
+    gl2ps->lastvertex = prim->verts[1];
+    gl2psSetLastColor(prim->verts[0].rgba);
+    gl2ps->lastlinewidth = prim->width;
+    gl2ps->lastpattern = prim->pattern;
+    gl2ps->lastfactor = prim->factor;
+    if(newline){
+      gl2psSVGGetColorString(rgba[0], col);
+      gl2psPrintf("<polyline fill=\"none\" stroke=\"%s\" stroke-width=\"%g\" ", 
+                  col, prim->width);
+      if(rgba[0][3] < 1.0F) gl2psPrintf("stroke-opacity=\"%g\" ", rgba[0][3]);
+      gl2psPrintSVGDash(prim->pattern, prim->factor);
+      gl2psPrintf("points=\"%g,%g ", xyz[0][0], xyz[0][1]);
+    }
+    else{
+      gl2psPrintf("%g,%g ", xyz[0][0], xyz[0][1]);
+    }
+    break;
+  case GL2PS_TRIANGLE :
+    gl2psPrintSVGSmoothTriangle(xyz, rgba);
+    break;
+  case GL2PS_QUADRANGLE :
+    gl2psMsg(GL2PS_WARNING, "There should not be any quad left to print");
+    break;
+  case GL2PS_PIXMAP :
+    gl2psPrintSVGPixmap(xyz[0][0], xyz[0][1], prim->data.image);
+    break;
+  case GL2PS_TEXT :
+    gl2psSVGGetColorString(prim->verts[0].rgba, col);
+    gl2psPrintf("<text fill=\"%s\" x=\"%g\" y=\"%g\" font-size=\"%d\" ",
+                col, xyz[0][0], xyz[0][1], prim->data.text->fontsize);
+    if(prim->data.text->angle)
+      gl2psPrintf("transform=\"rotate(%g, %g, %g)\" ",
+                  -prim->data.text->angle, xyz[0][0], xyz[0][1]);
+    if(!strcmp(prim->data.text->fontname, "Times-Roman"))
+      gl2psPrintf("font-family=\"Times\">");
+    else if(!strcmp(prim->data.text->fontname, "Times-Bold"))
+      gl2psPrintf("font-family=\"Times\" font-weight=\"bold\">");
+    else if(!strcmp(prim->data.text->fontname, "Times-Italic"))
+      gl2psPrintf("font-family=\"Times\" font-style=\"italic\">");
+    else if(!strcmp(prim->data.text->fontname, "Times-BoldItalic"))
+      gl2psPrintf("font-family=\"Times\" font-style=\"italic\" font-weight=\"bold\">");
+    else if(!strcmp(prim->data.text->fontname, "Helvetica-Bold"))
+      gl2psPrintf("font-family=\"Helvetica\" font-weight=\"bold\">");
+    else if(!strcmp(prim->data.text->fontname, "Helvetica-Oblique"))
+      gl2psPrintf("font-family=\"Helvetica\" font-style=\"oblique\">");
+    else if(!strcmp(prim->data.text->fontname, "Helvetica-BoldOblique"))
+      gl2psPrintf("font-family=\"Helvetica\" font-style=\"oblique\" font-weight=\"bold\">");
+    else if(!strcmp(prim->data.text->fontname, "Courier-Bold"))
+      gl2psPrintf("font-family=\"Courier\" font-weight=\"bold\">");
+    else if(!strcmp(prim->data.text->fontname, "Courier-Oblique"))
+      gl2psPrintf("font-family=\"Courier\" font-style=\"oblique\">");
+    else if(!strcmp(prim->data.text->fontname, "Courier-BoldOblique"))
+      gl2psPrintf("font-family=\"Courier\" font-style=\"oblique\" font-weight=\"bold\">");
+    else
+      gl2psPrintf("font-family=\"%s\">", prim->data.text->fontname);
+    gl2psPrintf("%s</text>\n", prim->data.text->str);
+    break;
+  case GL2PS_SPECIAL :
+    /* alignment contains the format for which the special output text
+       is intended */
+    if(prim->data.text->alignment == GL2PS_SVG)
+      gl2psPrintf("%s\n", prim->data.text->str);
+    break;
+  default :
+    break;
+  }
+}
+
+static void gl2psPrintSVGFooter(void)
+{
+  gl2psPrintf("</g>\n");
+  gl2psPrintf("</svg>\n");  
+  
+  gl2psPrintGzipFooter();
+}
+
+static void gl2psPrintSVGBeginViewport(GLint viewport[4])
+{
+  GLint index;
+  char col[32];
+  GLfloat rgba[4];
+  int x = viewport[0], y = viewport[1], w = viewport[2], h = viewport[3];
+
+  glRenderMode(GL_FEEDBACK);
+  
+  if(gl2ps->header){
+    gl2psPrintSVGHeader();
+    gl2ps->header = GL_FALSE;
+  }
+
+  if(gl2ps->options & GL2PS_DRAW_BACKGROUND){
+    if(gl2ps->colormode == GL_RGBA || gl2ps->colorsize == 0){
+      glGetFloatv(GL_COLOR_CLEAR_VALUE, rgba);
+    }
+    else{
+      glGetIntegerv(GL_INDEX_CLEAR_VALUE, &index);
+      rgba[0] = gl2ps->colormap[index][0];
+      rgba[1] = gl2ps->colormap[index][1];
+      rgba[2] = gl2ps->colormap[index][2];
+      rgba[3] = 1.0F;
+    }
+    gl2psSVGGetColorString(rgba, col);
+    gl2psPrintf("<polygon fill=\"%s\" points=\"%d,%d %d,%d %d,%d %d,%d\"/>\n", col, 
+                x, gl2ps->viewport[3] - y, 
+                x + w, gl2ps->viewport[3] - y, 
+                x + w, gl2ps->viewport[3] - (y + h), 
+                x, gl2ps->viewport[3] - (y + h));
+  }
+
+  gl2psPrintf("<clipPath id=\"cp%d%d%d%d\">\n", x, y, w, h);
+  gl2psPrintf("  <polygon points=\"%d,%d %d,%d %d,%d %d,%d\"/>\n", 
+              x, gl2ps->viewport[3] - y, 
+              x + w, gl2ps->viewport[3] - y, 
+              x + w, gl2ps->viewport[3] - (y + h), 
+              x, gl2ps->viewport[3] - (y + h));
+  gl2psPrintf("</clipPath>\n");
+  gl2psPrintf("<g clip-path=\"url(#cp%d%d%d%d)\">\n", x, y, w, h);
+}
+
+static GLint gl2psPrintSVGEndViewport(void)
+{
+  GLint res;
+
+  res = gl2psPrintPrimitives();
+  gl2psPrintf("</g>\n");
+  return res;
+}
+
+static void gl2psPrintSVGFinalPrimitive(void)
+{
+  /* End any remaining line, if any */
+  gl2psEndSVGLine();
+}
+
+/* definition of the SVG backend */
+
+static GL2PSbackend gl2psSVG = {
+  gl2psPrintSVGHeader,
+  gl2psPrintSVGFooter,
+  gl2psPrintSVGBeginViewport,
+  gl2psPrintSVGEndViewport,
+  gl2psPrintSVGPrimitive,
+  gl2psPrintSVGFinalPrimitive,
+  "svg",
+  "Scalable Vector Graphics"
+};
+
+/*********************************************************************
+ *
+ * PGF routines
+ *
+ *********************************************************************/
+
+static void gl2psPrintPGFColor(GL2PSrgba rgba)
+{
+  if(!gl2psSameColor(gl2ps->lastrgba, rgba)){
+    gl2psSetLastColor(rgba);
+    fprintf(gl2ps->stream, "\\color[rgb]{%f,%f,%f}\n", rgba[0], rgba[1], rgba[2]);
+  }
+}
+
+static void gl2psPrintPGFHeader(void)
+{
+  time_t now;
+
+  time(&now);
+
+  fprintf(gl2ps->stream, 
+          "%% Title: %s\n"
+          "%% Creator: GL2PS %d.%d.%d%s, %s\n"
+          "%% For: %s\n"
+          "%% CreationDate: %s",
+          gl2ps->title, GL2PS_MAJOR_VERSION, GL2PS_MINOR_VERSION,
+          GL2PS_PATCH_VERSION, GL2PS_EXTRA_VERSION, GL2PS_COPYRIGHT,
+          gl2ps->producer, ctime(&now));
+
+  fprintf(gl2ps->stream, "\\begin{pgfpicture}\n");
+  if(gl2ps->options & GL2PS_DRAW_BACKGROUND){
+    gl2psPrintPGFColor(gl2ps->bgcolor);
+    fprintf(gl2ps->stream,
+            "\\pgfpathrectanglecorners{"
+            "\\pgfpoint{%dpt}{%dpt}}{\\pgfpoint{%dpt}{%dpt}}\n"
+            "\\pgfusepath{fill}\n",
+            (int)gl2ps->viewport[0], (int)gl2ps->viewport[1],
+            (int)gl2ps->viewport[2], (int)gl2ps->viewport[3]);
+  }
+}
+
+static void gl2psPrintPGFDash(GLushort pattern, GLint factor)
+{
+  int i, n, array[10];
+
+  if(pattern == gl2ps->lastpattern && factor == gl2ps->lastfactor)
+    return;
+
+  gl2ps->lastpattern = pattern;
+  gl2ps->lastfactor = factor;
+
+  if(!pattern || !factor){
+    /* solid line */
+    fprintf(gl2ps->stream, "\\pgfsetdash{}{0pt}\n");
+  }
+  else{
+    gl2psParseStipplePattern(pattern, factor, &n, array);
+    fprintf(gl2ps->stream, "\\pgfsetdash{");
+    for(i = 0; i < n; i++) fprintf(gl2ps->stream, "{%dpt}", array[i]);
+    fprintf(gl2ps->stream, "}{0pt}\n");
+  }
+}
+
+static const char *gl2psPGFTextAlignment(int align)
+{
+  switch(align){
+  case GL2PS_TEXT_C  : return "center";
+  case GL2PS_TEXT_CL : return "west";
+  case GL2PS_TEXT_CR : return "east";
+  case GL2PS_TEXT_B  : return "south";
+  case GL2PS_TEXT_BR : return "south east";
+  case GL2PS_TEXT_T  : return "north";
+  case GL2PS_TEXT_TL : return "north west";
+  case GL2PS_TEXT_TR : return "north east";
+  case GL2PS_TEXT_BL : 
+  default            : return "south west";
+  }
+}
+
+static void gl2psPrintPGFPrimitive(void *data)
+{
+  GL2PSprimitive *prim;
+
+  prim = *(GL2PSprimitive**)data;
+
+  switch(prim->type){
+  case GL2PS_POINT :
+    /* Points in openGL are rectangular */
+    gl2psPrintPGFColor(prim->verts[0].rgba);
+    fprintf(gl2ps->stream, 
+            "\\pgfpathrectangle{\\pgfpoint{%fpt}{%fpt}}"
+            "{\\pgfpoint{%fpt}{%fpt}}\n\\pgfusepath{fill}\n",
+            prim->verts[0].xyz[0]-0.5*prim->width,
+            prim->verts[0].xyz[1]-0.5*prim->width,
+            prim->width,prim->width);
+    break;
+  case GL2PS_LINE :
+    gl2psPrintPGFColor(prim->verts[0].rgba);
+    if(gl2ps->lastlinewidth != prim->width){
+      gl2ps->lastlinewidth = prim->width;
+      fprintf(gl2ps->stream, "\\pgfsetlinewidth{%fpt}\n", gl2ps->lastlinewidth);
+    }
+    gl2psPrintPGFDash(prim->pattern, prim->factor);
+    fprintf(gl2ps->stream, 
+            "\\pgfpathmoveto{\\pgfpoint{%fpt}{%fpt}}\n"
+            "\\pgflineto{\\pgfpoint{%fpt}{%fpt}}\n"
+            "\\pgfusepath{stroke}\n",
+            prim->verts[1].xyz[0], prim->verts[1].xyz[1],
+            prim->verts[0].xyz[0], prim->verts[0].xyz[1]);
+    break;
+  case GL2PS_TRIANGLE :
+    if(gl2ps->lastlinewidth != 0){
+      gl2ps->lastlinewidth = 0;
+      fprintf(gl2ps->stream, "\\pgfsetlinewidth{0.01pt}\n");
+    }
+    gl2psPrintPGFColor(prim->verts[0].rgba);
+    fprintf(gl2ps->stream, 
+            "\\pgfpathmoveto{\\pgfpoint{%fpt}{%fpt}}\n"
+            "\\pgflineto{\\pgfpoint{%fpt}{%fpt}}\n"
+            "\\pgflineto{\\pgfpoint{%fpt}{%fpt}}\n"
+            "\\pgfpathclose\n"
+            "\\pgfusepath{fill,stroke}\n",
+            prim->verts[2].xyz[0], prim->verts[2].xyz[1],
+            prim->verts[1].xyz[0], prim->verts[1].xyz[1],
+            prim->verts[0].xyz[0], prim->verts[0].xyz[1]);
+    break;
+  case GL2PS_TEXT :
+    fprintf(gl2ps->stream, "{\n\\pgftransformshift{\\pgfpoint{%fpt}{%fpt}}\n",
+            prim->verts[0].xyz[0], prim->verts[0].xyz[1]);
+
+    if(prim->data.text->angle)
+      fprintf(gl2ps->stream, "\\pgftransformrotate{%f}{", prim->data.text->angle);
+
+    fprintf(gl2ps->stream, "\\pgfnode{rectangle}{%s}{\\fontsize{%d}{0}\\selectfont",
+            gl2psPGFTextAlignment(prim->data.text->alignment),
+            prim->data.text->fontsize);
+
+    fprintf(gl2ps->stream, "\\textcolor[rgb]{%g,%g,%g}{{%s}}",
+            prim->verts[0].rgba[0], prim->verts[0].rgba[1],
+            prim->verts[0].rgba[2], prim->data.text->str);
+
+    fprintf(gl2ps->stream, "}{}{\\pgfusepath{discard}}}\n");
+    break;
+  case GL2PS_SPECIAL :
+    /* alignment contains the format for which the special output text
+       is intended */
+    if (prim->data.text->alignment == GL2PS_PGF)
+      fprintf(gl2ps->stream, "%s\n", prim->data.text->str);
+    break;
+  default :
+    break;
+  }
+}
+
+static void gl2psPrintPGFFooter(void)
+{
+  fprintf(gl2ps->stream, "\\end{pgfpicture}\n");
+}
+
+static void gl2psPrintPGFBeginViewport(GLint viewport[4])
+{
+  GLint index;
+  GLfloat rgba[4];
+  int x = viewport[0], y = viewport[1], w = viewport[2], h = viewport[3];
+
+  glRenderMode(GL_FEEDBACK);
+
+  if(gl2ps->header){
+    gl2psPrintPGFHeader();
+    gl2ps->header = GL_FALSE;
+  }
+
+  fprintf(gl2ps->stream, "\\begin{pgfscope}\n");
+  if(gl2ps->options & GL2PS_DRAW_BACKGROUND){
+    if(gl2ps->colormode == GL_RGBA || gl2ps->colorsize == 0){
+      glGetFloatv(GL_COLOR_CLEAR_VALUE, rgba);
+    }
+    else{
+      glGetIntegerv(GL_INDEX_CLEAR_VALUE, &index);
+      rgba[0] = gl2ps->colormap[index][0];
+      rgba[1] = gl2ps->colormap[index][1];
+      rgba[2] = gl2ps->colormap[index][2];
+      rgba[3] = 1.0F;
+    }
+    gl2psPrintPGFColor(rgba);
+    fprintf(gl2ps->stream, 
+            "\\pgfpathrectangle{\\pgfpoint{%dpt}{%dpt}}"
+            "{\\pgfpoint{%dpt}{%dpt}}\n"
+            "\\pgfusepath{fill}\n",
+            x, y, w, h);
+  }
+  
+  fprintf(gl2ps->stream, 
+          "\\pgfpathrectangle{\\pgfpoint{%dpt}{%dpt}}"
+          "{\\pgfpoint{%dpt}{%dpt}}\n"
+          "\\pgfusepath{clip}\n",
+          x, y, w, h);
+}
+
+static GLint gl2psPrintPGFEndViewport(void)
+{
+  GLint res;
+  res = gl2psPrintPrimitives();
+  fprintf(gl2ps->stream, "\\end{pgfscope}\n");
+  return res;
+}
+
+static void gl2psPrintPGFFinalPrimitive(void)
+{
+}
+
+/* definition of the PGF backend */
+
+static GL2PSbackend gl2psPGF = {
+  gl2psPrintPGFHeader,
+  gl2psPrintPGFFooter,
+  gl2psPrintPGFBeginViewport,
+  gl2psPrintPGFEndViewport,
+  gl2psPrintPGFPrimitive,
+  gl2psPrintPGFFinalPrimitive,
+  "tex",
+  "PGF Latex Graphics"
+};
+
+/********************************************************************* 
+ *
+ * General primitive printing routine
+ *
+ *********************************************************************/
+
+/* Warning: the ordering of the backends must match the format
+   #defines in gl2ps.h */
+
+static GL2PSbackend *gl2psbackends[] = {
+  &gl2psPS,  /* 0 */
+  &gl2psEPS, /* 1 */
+  &gl2psTEX, /* 2 */
+  &gl2psPDF, /* 3 */
+  &gl2psSVG, /* 4 */
+  &gl2psPGF  /* 5 */
+};
+
+static void gl2psComputeTightBoundingBox(void *data)
+{
+  GL2PSprimitive *prim;
+  int i;
+
+  prim = *(GL2PSprimitive**)data;
+
+  for(i = 0; i < prim->numverts; i++){
+    if(prim->verts[i].xyz[0] < gl2ps->viewport[0])
+      gl2ps->viewport[0] = (GLint)prim->verts[i].xyz[0];
+    if(prim->verts[i].xyz[0] > gl2ps->viewport[2])
+      gl2ps->viewport[2] = (GLint)(prim->verts[i].xyz[0] + 0.5F);
+    if(prim->verts[i].xyz[1] < gl2ps->viewport[1])
+      gl2ps->viewport[1] = (GLint)prim->verts[i].xyz[1];
+    if(prim->verts[i].xyz[1] > gl2ps->viewport[3])
+      gl2ps->viewport[3] = (GLint)(prim->verts[i].xyz[1] + 0.5F);
+  }
+}  
+
+static GLint gl2psPrintPrimitives(void)
+{
+  GL2PSbsptree *root;
+  GL2PSxyz eye = {0.0F, 0.0F, 100.0F * GL2PS_ZSCALE};
+  GLint used;
+
+  used = glRenderMode(GL_RENDER);
+
+  if(used < 0){
+    gl2psMsg(GL2PS_INFO, "OpenGL feedback buffer overflow");
+    return GL2PS_OVERFLOW;
+  }
+
+  if(used > 0)
+    gl2psParseFeedbackBuffer(used);
+
+  gl2psRescaleAndOffset();
+
+  if(gl2ps->header){
+    if(gl2psListNbr(gl2ps->primitives) && 
+       (gl2ps->options & GL2PS_TIGHT_BOUNDING_BOX)){
+      gl2ps->viewport[0] = gl2ps->viewport[1] = 100000;
+      gl2ps->viewport[2] = gl2ps->viewport[3] = -100000;
+      gl2psListAction(gl2ps->primitives, gl2psComputeTightBoundingBox);
+    }
+    (gl2psbackends[gl2ps->format]->printHeader)();
+    gl2ps->header = GL_FALSE;
+  }
+
+  if(!gl2psListNbr(gl2ps->primitives)){
+    /* empty feedback buffer and/or nothing else to print */
+    return GL2PS_NO_FEEDBACK;
+  }
+
+  switch(gl2ps->sort){
+  case GL2PS_NO_SORT :
+    gl2psListAction(gl2ps->primitives, gl2psbackends[gl2ps->format]->printPrimitive);
+    gl2psListAction(gl2ps->primitives, gl2psFreePrimitive);
+    /* reset the primitive list, waiting for the next viewport */
+    gl2psListReset(gl2ps->primitives);
+    break;
+  case GL2PS_SIMPLE_SORT :
+    gl2psListSort(gl2ps->primitives, gl2psCompareDepth);
+    if(gl2ps->options & GL2PS_OCCLUSION_CULL){
+      gl2psListActionInverse(gl2ps->primitives, gl2psAddInImageTree);
+      gl2psFreeBspImageTree(&gl2ps->imagetree);
+    }
+    gl2psListAction(gl2ps->primitives, gl2psbackends[gl2ps->format]->printPrimitive);
+    gl2psListAction(gl2ps->primitives, gl2psFreePrimitive);
+    /* reset the primitive list, waiting for the next viewport */
+    gl2psListReset(gl2ps->primitives);
+    break;
+  case GL2PS_BSP_SORT :
+    root = (GL2PSbsptree*)gl2psMalloc(sizeof(GL2PSbsptree));
+    gl2psBuildBspTree(root, gl2ps->primitives);
+    if(GL_TRUE == gl2ps->boundary) gl2psBuildPolygonBoundary(root);
+    if(gl2ps->options & GL2PS_OCCLUSION_CULL){
+      gl2psTraverseBspTree(root, eye, -GL2PS_EPSILON, gl2psLess,
+                           gl2psAddInImageTree, 1);
+      gl2psFreeBspImageTree(&gl2ps->imagetree);
+    }
+    gl2psTraverseBspTree(root, eye, GL2PS_EPSILON, gl2psGreater, 
+                         gl2psbackends[gl2ps->format]->printPrimitive, 0);
+    gl2psFreeBspTree(&root);
+    /* reallocate the primitive list (it's been deleted by
+       gl2psBuildBspTree) in case there is another viewport */
+    gl2ps->primitives = gl2psListCreate(500, 500, sizeof(GL2PSprimitive*));
+    break;
+  }
+  gl2psbackends[gl2ps->format]->printFinalPrimitive();
+
+  return GL2PS_SUCCESS;
+}
+
+/********************************************************************* 
+ *
+ * Public routines
+ *
+ *********************************************************************/
+
+GL2PSDLL_API GLint gl2psBeginPage(const char *title, const char *producer, 
+                                  GLint viewport[4], GLint format, GLint sort,
+                                  GLint options, GLint colormode,
+                                  GLint colorsize, GL2PSrgba *colormap,
+                                  GLint nr, GLint ng, GLint nb, GLint buffersize,
+                                  FILE *stream, const char *filename)
+{
+  GLint index;
+  int i;
+
+  if(gl2ps){
+    gl2psMsg(GL2PS_ERROR, "gl2psBeginPage called in wrong program state");
+    return GL2PS_ERROR;
+  }
+
+  gl2ps = (GL2PScontext*)gl2psMalloc(sizeof(GL2PScontext));
+
+  if(format >= 0 && format < (GLint)(sizeof(gl2psbackends) / sizeof(gl2psbackends[0]))){
+    gl2ps->format = format;
+  }
+  else {
+    gl2psMsg(GL2PS_ERROR, "Unknown output format: %d", format);
+    gl2psFree(gl2ps);
+    gl2ps = NULL;
+    return GL2PS_ERROR;
+  }
+
+  switch(sort){
+  case GL2PS_NO_SORT :
+  case GL2PS_SIMPLE_SORT :
+  case GL2PS_BSP_SORT :
+    gl2ps->sort = sort;
+    break;
+  default :
+    gl2psMsg(GL2PS_ERROR, "Unknown sorting algorithm: %d", sort);
+    gl2psFree(gl2ps);
+    gl2ps = NULL;
+    return GL2PS_ERROR;
+  }
+
+  if(stream){
+    gl2ps->stream = stream;
+  }
+  else{
+    gl2psMsg(GL2PS_ERROR, "Bad file pointer");
+    gl2psFree(gl2ps);
+    gl2ps = NULL;
+    return GL2PS_ERROR;
+  }
+
+  gl2ps->header = GL_TRUE;
+  gl2ps->maxbestroot = 10;
+  gl2ps->options = options;
+  gl2ps->compress = NULL;
+  gl2ps->imagemap_head = NULL;
+  gl2ps->imagemap_tail = NULL;
+
+  if(gl2ps->options & GL2PS_USE_CURRENT_VIEWPORT){
+    glGetIntegerv(GL_VIEWPORT, gl2ps->viewport);
+  }
+  else{
+    for(i = 0; i < 4; i++){
+      gl2ps->viewport[i] = viewport[i];
+    }
+  }
+
+  if(!gl2ps->viewport[2] || !gl2ps->viewport[3]){
+    gl2psMsg(GL2PS_ERROR, "Incorrect viewport (x=%d, y=%d, width=%d, height=%d)",
+             gl2ps->viewport[0], gl2ps->viewport[1], 
+             gl2ps->viewport[2], gl2ps->viewport[3]);
+    gl2psFree(gl2ps);
+    gl2ps = NULL;
+    return GL2PS_ERROR;
+  }
+
+  gl2ps->threshold[0] = nr ? 1.0F / (GLfloat)nr : 0.064F;
+  gl2ps->threshold[1] = ng ? 1.0F / (GLfloat)ng : 0.034F;
+  gl2ps->threshold[2] = nb ? 1.0F / (GLfloat)nb : 0.100F;
+  gl2ps->colormode = colormode;
+  gl2ps->buffersize = buffersize > 0 ? buffersize : 2048 * 2048;
+  for(i = 0; i < 3; i++){
+    gl2ps->lastvertex.xyz[i] = -1.0F;
+  }
+  for(i = 0; i < 4; i++){
+    gl2ps->lastvertex.rgba[i] = -1.0F;
+    gl2ps->lastrgba[i] = -1.0F;
+  }
+  gl2ps->lastlinewidth = -1.0F;
+  gl2ps->lastpattern = 0;
+  gl2ps->lastfactor = 0;
+  gl2ps->imagetree = NULL;
+  gl2ps->primitivetoadd = NULL;
+  gl2ps->zerosurfacearea = GL_FALSE;  
+  gl2ps->pdfprimlist = NULL;
+  gl2ps->pdfgrouplist = NULL;
+  gl2ps->xreflist = NULL;
+  
+  /* get default blending mode from current OpenGL state (enabled by
+     default for SVG) */
+  gl2ps->blending = (gl2ps->format == GL2PS_SVG) ? GL_TRUE : glIsEnabled(GL_BLEND);
+  glGetIntegerv(GL_BLEND_SRC, &gl2ps->blendfunc[0]);
+  glGetIntegerv(GL_BLEND_DST, &gl2ps->blendfunc[1]);
+
+  if(gl2ps->colormode == GL_RGBA){
+    gl2ps->colorsize = 0;
+    gl2ps->colormap = NULL;
+    glGetFloatv(GL_COLOR_CLEAR_VALUE, gl2ps->bgcolor);
+  }
+  else if(gl2ps->colormode == GL_COLOR_INDEX){
+    if(!colorsize || !colormap){
+      gl2psMsg(GL2PS_ERROR, "Missing colormap for GL_COLOR_INDEX rendering");
+      gl2psFree(gl2ps);
+      gl2ps = NULL;
+      return GL2PS_ERROR;
+    }
+    gl2ps->colorsize = colorsize;
+    gl2ps->colormap = (GL2PSrgba*)gl2psMalloc(gl2ps->colorsize * sizeof(GL2PSrgba));
+    memcpy(gl2ps->colormap, colormap, gl2ps->colorsize * sizeof(GL2PSrgba));
+    glGetIntegerv(GL_INDEX_CLEAR_VALUE, &index);
+    gl2ps->bgcolor[0] = gl2ps->colormap[index][0];
+    gl2ps->bgcolor[1] = gl2ps->colormap[index][1];
+    gl2ps->bgcolor[2] = gl2ps->colormap[index][2];
+    gl2ps->bgcolor[3] = 1.0F;
+  }
+  else{
+    gl2psMsg(GL2PS_ERROR, "Unknown color mode in gl2psBeginPage");
+    gl2psFree(gl2ps);
+    gl2ps = NULL;
+    return GL2PS_ERROR;
+  }
+
+  if(!title){
+    gl2ps->title = (char*)gl2psMalloc(sizeof(char));
+    gl2ps->title[0] = '\0';
+  }
+  else{
+    gl2ps->title = (char*)gl2psMalloc((strlen(title)+1)*sizeof(char));
+    strcpy(gl2ps->title, title);
+  }
+    
+  if(!producer){
+    gl2ps->producer = (char*)gl2psMalloc(sizeof(char));
+    gl2ps->producer[0] = '\0';
+  }
+  else{
+    gl2ps->producer = (char*)gl2psMalloc((strlen(producer)+1)*sizeof(char));
+    strcpy(gl2ps->producer, producer);
+  }
+  
+  if(!filename){
+    gl2ps->filename = (char*)gl2psMalloc(sizeof(char));
+    gl2ps->filename[0] = '\0';
+  }
+  else{
+    gl2ps->filename = (char*)gl2psMalloc((strlen(filename)+1)*sizeof(char));
+    strcpy(gl2ps->filename, filename);
+  }
+
+  gl2ps->primitives = gl2psListCreate(500, 500, sizeof(GL2PSprimitive*));
+  gl2ps->auxprimitives = gl2psListCreate(100, 100, sizeof(GL2PSprimitive*));
+  gl2ps->feedback = (GLfloat*)gl2psMalloc(gl2ps->buffersize * sizeof(GLfloat));
+  glFeedbackBuffer(gl2ps->buffersize, GL_3D_COLOR, gl2ps->feedback);
+  glRenderMode(GL_FEEDBACK);  
+
+  return GL2PS_SUCCESS;
+}
+
+GL2PSDLL_API GLint gl2psEndPage(void)
+{
+  GLint res;
+
+  if(!gl2ps) return GL2PS_UNINITIALIZED;
+
+  res = gl2psPrintPrimitives();
+
+  if(res != GL2PS_OVERFLOW)
+    (gl2psbackends[gl2ps->format]->printFooter)();
+  
+  fflush(gl2ps->stream);
+
+  gl2psListDelete(gl2ps->primitives);
+  gl2psListDelete(gl2ps->auxprimitives);
+  gl2psFreeImagemap(gl2ps->imagemap_head);
+  gl2psFree(gl2ps->colormap);
+  gl2psFree(gl2ps->title);
+  gl2psFree(gl2ps->producer);
+  gl2psFree(gl2ps->filename);
+  gl2psFree(gl2ps->feedback);
+  gl2psFree(gl2ps);
+  gl2ps = NULL;
+
+  return res;
+}
+
+GL2PSDLL_API GLint gl2psBeginViewport(GLint viewport[4])
+{
+  if(!gl2ps) return GL2PS_UNINITIALIZED;
+
+  (gl2psbackends[gl2ps->format]->beginViewport)(viewport);
+  
+  return GL2PS_SUCCESS;
+}
+
+GL2PSDLL_API GLint gl2psEndViewport(void)
+{
+  GLint res;
+
+  if(!gl2ps) return GL2PS_UNINITIALIZED;
+
+  res = (gl2psbackends[gl2ps->format]->endViewport)();
+
+  /* reset last used colors, line widths */
+  gl2ps->lastlinewidth = -1.0F;
+
+  return res;
+}
+
+GL2PSDLL_API GLint gl2psTextOpt(const char *str, const char *fontname, 
+                                GLshort fontsize, GLint alignment, GLfloat angle)
+{
+  return gl2psAddText(GL2PS_TEXT, str, fontname, fontsize, alignment, angle);
+}
+
+GL2PSDLL_API GLint gl2psText(const char *str, const char *fontname, GLshort fontsize)
+{
+  return gl2psAddText(GL2PS_TEXT, str, fontname, fontsize, GL2PS_TEXT_BL, 0.0F);
+}
+
+GL2PSDLL_API GLint gl2psSpecial(GLint format, const char *str)
+{
+  return gl2psAddText(GL2PS_SPECIAL, str, "", 0, format, 0.0F);
+}
+
+GL2PSDLL_API GLint gl2psDrawPixels(GLsizei width, GLsizei height,
+                                   GLint xorig, GLint yorig,
+                                   GLenum format, GLenum type, 
+                                   const void *pixels)
+{
+  int size, i;
+  GLfloat pos[4], *piv;
+  GL2PSprimitive *prim;
+  GLboolean valid;
+
+  if(!gl2ps || !pixels) return GL2PS_UNINITIALIZED;
+
+  if((width <= 0) || (height <= 0)) return GL2PS_ERROR;
+
+  if(gl2ps->options & GL2PS_NO_PIXMAP) return GL2PS_SUCCESS;
+
+  if((format != GL_RGB && format != GL_RGBA) || type != GL_FLOAT){
+    gl2psMsg(GL2PS_ERROR, "gl2psDrawPixels only implemented for "
+             "GL_RGB/GL_RGBA, GL_FLOAT pixels");
+    return GL2PS_ERROR;
+  }
+
+  glGetBooleanv(GL_CURRENT_RASTER_POSITION_VALID, &valid);
+  if(GL_FALSE == valid) return GL2PS_SUCCESS; /* the primitive is culled */
+
+  glGetFloatv(GL_CURRENT_RASTER_POSITION, pos);
+
+  prim = (GL2PSprimitive*)gl2psMalloc(sizeof(GL2PSprimitive));
+  prim->type = GL2PS_PIXMAP;
+  prim->boundary = 0;
+  prim->numverts = 1;
+  prim->verts = (GL2PSvertex*)gl2psMalloc(sizeof(GL2PSvertex));
+  prim->verts[0].xyz[0] = pos[0] + xorig;
+  prim->verts[0].xyz[1] = pos[1] + yorig;
+  prim->verts[0].xyz[2] = pos[2];
+  prim->culled = 0;
+  prim->offset = 0;
+  prim->pattern = 0;
+  prim->factor = 0;
+  prim->width = 1;
+  glGetFloatv(GL_CURRENT_RASTER_COLOR, prim->verts[0].rgba);
+  prim->data.image = (GL2PSimage*)gl2psMalloc(sizeof(GL2PSimage));
+  prim->data.image->width = width;
+  prim->data.image->height = height;
+  prim->data.image->format = format;
+  prim->data.image->type = type;
+
+  switch(format){
+  case GL_RGBA:
+    if(gl2ps->options & GL2PS_NO_BLENDING || !gl2ps->blending){
+      /* special case: blending turned off */
+      prim->data.image->format = GL_RGB;
+      size = height * width * 3;
+      prim->data.image->pixels = (GLfloat*)gl2psMalloc(size * sizeof(GLfloat));
+      piv = (GLfloat*)pixels;
+      for(i = 0; i < size; ++i, ++piv){
+        prim->data.image->pixels[i] = *piv;
+        if(!((i+1)%3))
+          ++piv;
+      }   
+    }
+    else{
+      size = height * width * 4;
+      prim->data.image->pixels = (GLfloat*)gl2psMalloc(size * sizeof(GLfloat));
+      memcpy(prim->data.image->pixels, pixels, size * sizeof(GLfloat));
+    }
+    break;
+  case GL_RGB:
+  default:
+    size = height * width * 3;
+    prim->data.image->pixels = (GLfloat*)gl2psMalloc(size * sizeof(GLfloat));
+    memcpy(prim->data.image->pixels, pixels, size * sizeof(GLfloat));
+    break;
+  }
+
+  gl2psListAdd(gl2ps->auxprimitives, &prim);
+  glPassThrough(GL2PS_DRAW_PIXELS_TOKEN);
+
+  return GL2PS_SUCCESS;
+}
+
+GL2PSDLL_API GLint gl2psDrawImageMap(GLsizei width, GLsizei height,
+                                     const GLfloat position[3],
+                                     const unsigned char *imagemap){
+  int size, i;
+  int sizeoffloat = sizeof(GLfloat);
+  
+  if(!gl2ps || !imagemap) return GL2PS_UNINITIALIZED;
+
+  if((width <= 0) || (height <= 0)) return GL2PS_ERROR;
+  
+  size = height + height * ((width - 1) / 8);
+  glPassThrough(GL2PS_IMAGEMAP_TOKEN);
+  glBegin(GL_POINTS);
+  glVertex3f(position[0], position[1],position[2]);
+  glEnd();
+  glPassThrough((GLfloat)width);
+  glPassThrough((GLfloat)height);
+  for(i = 0; i < size; i += sizeoffloat){
+    float *value = (float*)imagemap;
+    glPassThrough(*value);
+    imagemap += sizeoffloat;
+  }
+  return GL2PS_SUCCESS;
+}
+
+GL2PSDLL_API GLint gl2psEnable(GLint mode)
+{
+  GLint tmp;
+
+  if(!gl2ps) return GL2PS_UNINITIALIZED;
+
+  switch(mode){
+  case GL2PS_POLYGON_OFFSET_FILL :
+    glPassThrough(GL2PS_BEGIN_OFFSET_TOKEN);
+    glGetFloatv(GL_POLYGON_OFFSET_FACTOR, &gl2ps->offset[0]);
+    glGetFloatv(GL_POLYGON_OFFSET_UNITS, &gl2ps->offset[1]);
+    break;
+  case GL2PS_POLYGON_BOUNDARY :
+    glPassThrough(GL2PS_BEGIN_BOUNDARY_TOKEN);
+    break;
+  case GL2PS_LINE_STIPPLE :
+    glPassThrough(GL2PS_BEGIN_STIPPLE_TOKEN);
+    glGetIntegerv(GL_LINE_STIPPLE_PATTERN, &tmp);
+    glPassThrough((GLfloat)tmp);
+    glGetIntegerv(GL_LINE_STIPPLE_REPEAT, &tmp);
+    glPassThrough((GLfloat)tmp);
+    break;
+  case GL2PS_BLEND :
+    glPassThrough(GL2PS_BEGIN_BLEND_TOKEN);
+    break;
+  default :
+    gl2psMsg(GL2PS_WARNING, "Unknown mode in gl2psEnable: %d", mode);
+    return GL2PS_WARNING;
+  }
+
+  return GL2PS_SUCCESS;
+}
+
+GL2PSDLL_API GLint gl2psDisable(GLint mode)
+{
+  if(!gl2ps) return GL2PS_UNINITIALIZED;
+
+  switch(mode){
+  case GL2PS_POLYGON_OFFSET_FILL :
+    glPassThrough(GL2PS_END_OFFSET_TOKEN);
+    break;
+  case GL2PS_POLYGON_BOUNDARY :
+    glPassThrough(GL2PS_END_BOUNDARY_TOKEN);
+    break;
+  case GL2PS_LINE_STIPPLE :
+    glPassThrough(GL2PS_END_STIPPLE_TOKEN);
+    break;
+  case GL2PS_BLEND :
+    glPassThrough(GL2PS_END_BLEND_TOKEN);
+    break;
+  default :
+    gl2psMsg(GL2PS_WARNING, "Unknown mode in gl2psDisable: %d", mode);
+    return GL2PS_WARNING;
+  }
+
+  return GL2PS_SUCCESS;
+}
+
+GL2PSDLL_API GLint gl2psPointSize(GLfloat value)
+{
+  if(!gl2ps) return GL2PS_UNINITIALIZED;
+
+  glPassThrough(GL2PS_POINT_SIZE_TOKEN);
+  glPassThrough(value);
+  
+  return GL2PS_SUCCESS;
+}
+
+GL2PSDLL_API GLint gl2psLineWidth(GLfloat value)
+{
+  if(!gl2ps) return GL2PS_UNINITIALIZED;
+
+  glPassThrough(GL2PS_LINE_WIDTH_TOKEN);
+  glPassThrough(value);
+
+  return GL2PS_SUCCESS;
+}
+
+GL2PSDLL_API GLint gl2psBlendFunc(GLenum sfactor, GLenum dfactor)
+{
+  if(!gl2ps) return GL2PS_UNINITIALIZED;
+
+  if(GL_FALSE == gl2psSupportedBlendMode(sfactor, dfactor))
+    return GL2PS_WARNING;
+
+  glPassThrough(GL2PS_SRC_BLEND_TOKEN);
+  glPassThrough((GLfloat)sfactor);
+  glPassThrough(GL2PS_DST_BLEND_TOKEN);
+  glPassThrough((GLfloat)dfactor);
+
+  return GL2PS_SUCCESS;
+}
+
+GL2PSDLL_API GLint gl2psSetOptions(GLint options)
+{
+  if(!gl2ps) return GL2PS_UNINITIALIZED;
+
+  gl2ps->options = options;
+
+  return GL2PS_SUCCESS;
+}
+
+GL2PSDLL_API GLint gl2psGetOptions(GLint *options)
+{
+  if(!gl2ps) {
+    *options = 0;
+    return GL2PS_UNINITIALIZED;
+  }
+
+  *options = gl2ps->options;
+
+  return GL2PS_SUCCESS;
+}
+
+GL2PSDLL_API const char *gl2psGetFileExtension(GLint format)
+{
+  if(format >= 0 && format < (GLint)(sizeof(gl2psbackends) / sizeof(gl2psbackends[0])))
+    return gl2psbackends[format]->file_extension;
+  else
+    return "Unknown format";
+}
+
+GL2PSDLL_API const char *gl2psGetFormatDescription(GLint format)
+{
+  if(format >= 0 && format < (GLint)(sizeof(gl2psbackends) / sizeof(gl2psbackends[0])))
+    return gl2psbackends[format]->description;
+  else
+    return "Unknown format";
+}